Form 424B3 Nuwellis, Inc.

This prospectus (“prospectus”) relates to the offer and resale from time to time by the selling stockholders identified in this prospectus under the caption “Selling Stockholders” (the “selling stockholders”), including their permitted pledgees, assignees, donees, transferees or successor-in-interest, of up to 1,310,890 shares of common stock, $0.0001 par value per share (“common stock”) issuable upon the exercise of common stock purchase warrants issued on August 3, 2026 (“August Warrants”) in a private placement pursuant to a securities purchase agreement, dated as of July 31, 2026, by and among us and the purchasers named therein (the “August Purchase Agreement”). The August Warrants have an exercise price of $2.59 per share.

This prospectus also relates to the offer and resale from time to time of up to 39,327 shares of common stock issuable upon the exercise of common stock purchase warrants issued pursuant to a placement agent agreement, dated as of July 31, 2026, to Ladenburg Thalmann & Co. Inc. (the “Placement Agent”) or its designees on August 3, 2026 (the “PA Warrants,” and together with the August Warrants, the “Warrants”) in connection with the Private Placement. The PA Warrants have substantially the same terms as the August Warrants, except that the PA Warrants have an exercise price of $4.2735 per share.

The selling stockholders may offer, sell or distribute the shares of our common stock in a number of different ways and at varying prices. We provide more information about how the selling stockholders may offer, sell or distribute the shares of our common stock in the section of this prospectus titled “Plan of Distribution” beginning on page 11. We are not selling any securities under this prospectus and will not receive any of the proceeds from the sale of shares of our common stock by the selling stockholders. However, we will receive proceeds upon the cash exercise of any Warrants. See “Use of Proceeds” for more information.

We have paid or will pay the fees and expenses incident to the registration of the shares of our common stock for sale by the selling stockholders. The selling stockholders will bear all commissions, discounts, brokerage fees and similar expenses, if any, attributable to their sales of shares of our common stock.

We cannot predict when or in what amounts, if any, the Warrants will be exercised. We have paid or will pay the fees and expenses incident to the registration of the shares of our common stock for sale by the selling stockholders. The selling stockholders will bear all commissions, discounts, brokerage fees and similar expenses, if any, attributable to their sales of shares of our common stock.

Our common stock is listed on the Nasdaq Capital Market (“Nasdaq”) under the symbol “NUWE.” On August 14, 2026, the last reported sale price of our common stock as reported on Nasdaq was $1.31 per share.

We are a “smaller reporting company” as defined under U.S. federal securities laws and, as such, have elected to comply with reduced public company reporting requirements. See “Prospectus Summary - Implications of Being a Smaller Reporting Company.” This prospectus complies with the requirements that apply to an issuer that is a smaller reporting company.

An investment in our shares of common stock involves a high degree of risk. Before making any investment decision, you should carefully read the discussion of the material risks of investing in our shares of common stock in “Risk Factors” beginning on page 4 of this prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

This prospectus is part of a registration statement on Form S-3 that we filed with the Securities and Exchange Commission (the “SEC”) using the “shelf” registration process. Under this shelf registration process, the selling stockholders named in this prospectus may, from time to time, sell or otherwise distribute the shares of common stock offered by them as described in the section titled “Plan of Distribution” beginning on page 11 of this prospectus. We will not receive any of the proceeds from the sale of shares of our common stock by the selling stockholders; however, we will receive proceeds from the exercise of any July Warrants for cash. You should read this prospectus together with the more detailed information regarding the Company, our common stock, and our financial statements and notes to those statements that appear elsewhere in this prospectus and any applicable prospectus supplement together with the additional information that we incorporate in this prospectus by reference, which we describe under the heading “Where You Can Find More Information.”

Neither we nor the selling stockholders have authorized anyone to provide you with any information or to make any representations other than those contained in this prospectus or any applicable prospectus supplement or any free writing prospectuses prepared by or on behalf of us or to which we have referred you. Neither we nor the selling stockholders take responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. The selling stockholders are offering to sell, and seeking offers to buy, shares of their common stock only in jurisdictions where it is lawful to do so.

We may also provide a prospectus supplement or post-effective amendment to the Registration Statement to add information to, or update or change information contained in, this prospectus. You should rely only on the information contained in, or incorporated by reference in, this prospectus and in any accompanying prospectus supplement. We have not authorized anyone to provide you with different information from that contained in, or incorporated by reference in, this prospectus. You should not assume that the information in this prospectus or any prospectus supplement is accurate as of any date other than the date on the front of those documents or that any document incorporated by reference is accurate as of any date other than its filing date. You should not consider this prospectus to be an offer or solicitation relating to the shares of common stock in any jurisdiction in which such an offer or solicitation relating to the shares of common stock is not authorized. Furthermore, you should not consider this prospectus to be an offer or solicitation relating to the shares of common stock if the person making the offer or solicitation is not qualified to do so, or if it is unlawful for you to receive such an offer or solicitation.

In this prospectus, we frequently use the terms “we,” “our,” “us,” “Nuwellis”, “Registrant,” and the “Company” to refer to Nuwellis, Inc.

All trademarks or trade names referred to in this prospectus are the property of their respective owners. Solely for convenience, the trademarks and trade names in this prospectus are referred to without the ® and ™ symbols, but such references should not be construed as any indicator that their respective owners will not assert, to the fullest extent under applicable law, their rights thereto. We do not intend the use or display of other companies’ trademarks and trade names to imply a relationship with, or endorsement or sponsorship of us by, any other companies.

An investment in our shares of common stock involves a high degree of risk. You should consider carefully the risks described below, together with all of the other information included or incorporated by reference in this prospectus, including the risks and uncertainties discussed under Risk Factors” in our Annual Report on Form 10-K for our most recently completed fiscal year, in any Quarterly Reports on Form 10-Q that have been filed since our most recent Annual Report on Form 10-K for the year ended December 31, 2025 and Quarterly Reports on Form 10-Q for the periods ended March 31, 2026 and June 30, 2026, which is incorporated by reference and the other information in this prospectus and in any other documents that we file (not furnish) with the SEC under the Exchange Act. See “Where You Can Find More Information” and “Incorporation of Certain Documents by Reference.” The risks and uncertainties we have described are not the only ones we face. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also affect our operations. If any of these risks actually materialize, our business, prospects, financial condition, and results of operations could be seriously harmed. This could cause the trading price of our common stock and the value of the warrants to decline, resulting in a loss of all or part of your investment.

The exercise price of the August Warrants is $2.56 per share and the exercise price of the PA Warrants is $ 4.2735 per share. If the market price of our common stock does not exceed the exercise prices of the August Warrants or the PA Warrants during the respective exercise periods, holders of these warrants will be unlikely to exercise such warrants for cash. As a result, we may not receive any cash proceeds from the exercise of the August Warrants or the PA Warrants, which could adversely affect our liquidity and capital resources.

The selling stockholders may sell a significant number of shares of our common stock into the public market. Such sales, or the perception that such sales may occur, could adversely affect the market price of our common stock or increase volatility. The selling stockholders are not restricted as to the timing or amount of sales, and we cannot predict the effect that such sales may have on the trading price of our common stock.

This prospectus, and the documents that we have filed with the SEC that are incorporated by reference, contain “forward-looking statements” within the meaning of the safe harbor provisions of Section 27A of the Securities Act of 1933, as amended (the “Securities Act”) and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). Any statements about our expectations, beliefs, plans, objectives, assumptions or future events or performance are not historical facts and may be forward-looking uncertainties. In some cases, you can identify forward-looking statements by the use of words or phrases such as “anticipates,” “could,” “would,” “should,” “will,” “would,” “may,” “might,” “potential,” “contemplates,” “estimates,” “plans,” “seeks,” “projects,” “predicts,” “targets,” “objectives,” “continuing,” “ongoing,” “expects,” “management believes,” “we believe,” “we intend,” or the negative of these terms, or other comparable terminology intended to identify statements about the future. Any forward-looking statements are qualified in their entirety by reference to the factors discussed throughout this prospectus, and in particular those factors included in the sections entitled “Risk Factors” in this prospectus and in our most recent Annual Report on Form 10-K, our Quarterly Reports on Form 10-Q filed for the periods ended March 31, 2026 and June 30, 2026 and other filings we make with the SEC from time to time, which are on file with the SEC and incorporated herein by reference.

Forward-looking statements are based on management’s current expectations, estimates, forecasts and projections about our business and the industry in which we operate, and management’s beliefs and assumptions are not guarantees of future performance or development and involve known and unknown risks, uncertainties and other factors that are in some cases beyond our control. You should refer to the “Risk Factors” sections of our Annual Report on Form 10-K, our Quarterly Reports on Form 10-Q filed for the periods ended March 31, 2026 and June 30, 2026 and other filings we make with the SEC from time to time for a discussion of important factors that may cause our actual results to differ materially from those expressed or implied by our forward-looking statements. As a result of these factors, we cannot assure you that the forward-looking statements in this prospectus will prove to be accurate. Furthermore, if our forward-looking statements prove to be inaccurate, the inaccuracy may be material. In light of the significant uncertainties in these forward-looking statements, you should not regard these statements as a representation or warranty by us or any other person that we will achieve our objectives and plans in any specified time frame, or at all.

Forward-looking statements are subject to a number of risks and uncertainties that could cause actual events to adversely differ from the expectations indicated in these forward-looking statements, including without limitation, the risks and uncertainties described in this prospectus. Actual results could differ materially from those contained in forward-looking statements. Many factors could cause actual results to differ materially from those in forward-looking statements, including those matters discussed below, as well as those listed in the “Risk Factors” section contained herein, in any prospectus supplement and any related free writing prospectus, and under similar headings in the other documents that are incorporated by reference into this prospectus.

We operate in an evolving environment. New risk factors and uncertainties may emerge from time to time, and it is not possible for us to predict all risk factors and uncertainties. We may not actually achieve the plans, projections or expectations disclosed in forward-looking statements, and actual results, developments or events could differ materially from those disclosed in the forward-looking statements. Forward-looking statements are subject to a number of risks and uncertainties, including without limitation, the possibility that regulatory authorities do not accept our application or approve the marketing of our products, the possibility we may be unable to raise the funds necessary for the development and commercialization of our products, and those described in our filings with the SEC.

These risks include, among other things, that:

You should read this prospectus and the documents that we reference in this prospectus and have filed as exhibits to the Registration Statement of which this prospectus is a part with the understanding that our actual future results, levels of activity, performance and achievements may be different from what we expect. We qualify all of our forward-looking statements by these cautionary statements.

We are not selling any shares of common stock under this prospectus and we will not receive any proceeds from the sale of the shares of common stock by the selling stockholders. All net proceeds from the sale of the shares of common stock covered by this prospectus will go to the selling stockholders. We expect that the selling stockholders will sell their shares of common stock as described under “Plan of Distribution.” However, we will receive proceeds from the exercise of the Warrants by the selling stockholders to the extent they are exercised for cash. We estimate that the net proceeds that we would receive from the exercise of the Warrants, assuming all the Warrants are exercised at their respective exercise prices, will be approximately $3.6 million.

We do not know, however, whether any of the Warrants will be exercised or, if any of the Warrants are exercised, when they will be exercised. It is possible that the Warrants will expire and never be exercised. There are circumstances under which the Warrants may be exercised on a cashless basis. In these circumstances, even if the Warrants are exercised, we may not receive any proceeds, or the proceeds that we do receive may be significantly less than what we might expect. We intend to use the aggregate net proceeds from the exercise of any Warrants for king capital and general corporate purposes. The actual allocation of proceeds realized from the exercise of the Warrants will depend upon the amount and timing of such exercises, our cash position at such time and our working capital requirements.

The selling stockholders will pay any underwriting discounts and commissions and expenses incurred by the selling stockholders for brokerage, accounting, tax or legal services or any other expenses incurred by the selling stockholders in disposing of the shares of common stock. We will bear the costs, fees and expenses incurred in effecting the registration of the shares of common stock covered by this prospectus, including all registration and filing fees, Nasdaq listing fees and fees and expenses of our counsel and our independent registered public accounting firm.

On July 31, 2026, we entered into a placement agency agreement with the Placement Agent and the August Purchase Agreement with certain purchasers pursuant to which the Company agreed to sell, in a registered direct offering (the “August Registered Offering”), an aggregate of 1,310,890 shares (the “August Shares”) of the Company’s common stock at a purchase price of $2.59 per August Share.

The August Shares were sold pursuant to the Company’s effective shelf registration statement on Form S-3 (File No. 333-280647), including a base prospectus contained therein, which was originally filed with the SEC on July 1, 2024, and was declared effective by the SEC on July 9, 2024, and a related prospectus supplement, dated July 31, 2026, related to the August Registered Offering.

Pursuant to the August Purchase Agreement, in a concurrent private placement (the “August Private Placement” and together with the August Registered Offering, the “August 2026 Offering”), the Company also agreed to sell and issue to the selling stockholders the August Warrants to purchase up to 1,310,890 shares of common stock. The August Warrants have an exercise price of $2.59 per share, were immediately exercisable and expire five years following the date of effectiveness of the registration statement for the purposes of registering the shares of common stock underlying the August Warrants.

The August Warrants were issued to the selling stockholders, which are institutional accredited investors, in a private placement pursuant to Section 4(a)(2) and Regulation D promulgated under the Securities Act. Pursuant to the terms of the August Purchase Agreement, among other things, the Company is required to prepare and file with the SEC a registration statement to register for resale the shares of common stock issuable upon exercise of the August Warrants. The Company is required to use commercially reasonable efforts to have such registration statement declared effective as promptly as possible thereafter, and in any event no later than 60 days following August 3, 2026, or 90 days in the event of a review by the SEC.

Ladenburg Thalmann & Co. Inc. acted as the exclusive placement agent in connection with the August 2026 Offering, and as compensation in connection with the August 2026 Offering, we agreed to (i) pay the Placement Agent a cash fee equal to 9.0% of the gross proceeds of the August 2026 Offering, (ii) pay the Placement Agent up to $90,000 for its expenses in connection with such offering, and (iii) issue warrants to purchase up to 39,327 shares of common stock. The PA Warrants have substantially the same terms as the August Warrants described above, except that the PA Warrants have an exercise price of $4.2735 per share and expire five (5) years following the commencement of the sales pursuant to this offering.

The Private Placement Purchase Agreement contains customary representations, warranties and agreements by the Company, indemnification obligations of the Company, other obligations of the parties and termination provisions.

The gross proceeds from the Private Placement to us were approximately $3.4 million, before deducting the placement agent’s fees and related offering expenses. The Private Placement closed on August 3, 2026.

The shares of common stock being offered by the selling stockholders are those issuable to the selling stockholders, upon exercise of the August Warrants and/or the PA Warrants.

We are registering the shares of common stock in order to permit the selling stockholders to offer the shares for resale from time to time. The selling stockholders may sell all, some or none of their shares of common stock in this offering. For additional information, see the section titled “Plan of Distribution” beginning on page 11 of this prospectus.

The table below lists the selling stockholders and other information regarding the beneficial ownership of the shares of common stock by the selling stockholders as of August 7, 2026. The number of shares of our common stock outstanding as of August 7, 2026 was 3,647,264. The first column lists the number of shares of common stock beneficially owned by the selling stockholders prior to the offering, based on their respective ownership of the shares of common stock and securities convertible into shares of common stock within 60 days of August 7, 2026, excluding securities convertible into shares of common stock where such exercise would cause a selling stockholder’s beneficial ownership to exceed certain beneficial ownership limitations. The second column lists the shares of common stock being offered pursuant to this prospectus by the selling stockholders. The third and fourth columns list the number of shares of common stock owned after the offering and the percentage of common stock owned after the offering, assuming in both cases, the exercise of all of August Warrants and/or the PA Warrants, respectively, on that date, without regard to any limitations on the exercise of the Warrants being registered hereto and the sale of all of the shares of common stock offered by the selling stockholders pursuant to this prospectus. To our knowledge, and except as otherwise indicated below, based on the information provided to us by the selling stockholders, none of the selling stockholders has, or within the past three years has had, any position, office or other material relationship with us or any of our predecessors or affiliates.

The selling stockholders may sell some, all or none of the shares of common stock issuable upon exercise of the August Warrants and/or the PA Warrants. We do not know how long the selling stockholders will hold such shares of common stock before selling them, and we currently have no agreements, arrangements or understandings with the selling stockholders regarding the sale of any of the shares of common stock.

As discussed in greater detail above under the section of this prospectus entitled “Description of Private Placement” we entered into agreements with the selling stockholders pursuant to which they acquired the August Warrants and/or the PA Warrants, as applicable, and agreed, pursuant to a securities purchase agreement to file a registration statement to enable the resale of the shares of common stock issuable upon the exercise of the respective Warrants.

Except for Ladenburg Thalman & Co. Inc. who served as our placement agent or underwriter in a number of our prior offerings, none of the selling stockholders nor any persons having control over such selling stockholders have held any position or office with us or our affiliates within the last three years nor has had a material relationship with us or any of our predecessors or affiliates within the past three years, other than as a result of the ownership of our shares or other securities.

We are registering the shares of the common stock issuable upon exercise of the Warrants held by the selling stockholders to permit the resale of these shares of common stock by the holders of the shares of the common stock from time to time after the date of this prospectus. We will not receive any of the proceeds from the sale by the selling stockholders of the shares of the common stock. We will bear all fees and expenses incident to our obligation to register the shares of the common stock issuable upon exercise of the Warrants.

Each selling stockholder of the securities and any of their pledgees, assignees and successors-in-interest may, from time to time, sell any or all of their securities covered hereby on the principal Trading Market or any other stock exchange, market or trading facility on which the securities are traded or in private transactions. These sales may be at fixed or negotiated prices. A selling stockholder may use any one or more of the following methods when selling securities:

The selling stockholders may also sell securities under Rule 144 or any other exemption from registration under the Securities Act, if available, rather than under this prospectus.

Broker-dealers engaged by the selling stockholders may arrange for other brokers-dealers to participate in sales. Broker-dealers may receive commissions or discounts from the selling stockholders (or, if any broker-dealer acts as agent for the purchaser of securities, from the purchaser) in amounts to be negotiated, but, except as set forth in a supplement to this Prospectus, in the case of an agency transaction not in excess of a customary brokerage commission in compliance with FINRA Rule 2121; and in the case of a principal transaction a markup or markdown in compliance with FINRA Rule 2121.

In connection with the sale of the securities or interests therein, the selling stockholders may enter into hedging transactions with broker-dealers or other financial institutions, which may in turn engage in short sales of the securities in the course of hedging the positions they assume. The selling stockholders may also sell securities short and deliver these securities to close out their short positions, or loan or pledge the securities to broker-dealers that in turn may sell these securities. The selling stockholders may also enter into option or other transactions with broker-dealers or other financial institutions or create one or more derivative securities which require the delivery to such broker-dealer or other financial institution of securities offered by this prospectus, which securities such broker-dealer or other financial institution may resell pursuant to this prospectus (as supplemented or amended to reflect such transaction).

The selling stockholders and any broker-dealers or agents that are involved in selling the securities may be deemed to be “underwriters” within the meaning of the Securities Act in connection with such sales. In such event, any commissions received by such broker-dealers or agents and any profit on the resale of the securities purchased by them may be deemed to be underwriting commissions or discounts under the Securities Act. Each selling stockholder has informed us that it does not have any written or oral agreement or understanding, directly or indirectly, with any person to distribute the securities.

We are required to pay certain fees and expenses incurred by us incident to the registration of the securities. We have agreed to indemnify the selling stockholders against certain losses, claims, damages and liabilities, including liabilities under the Securities Act.

We agreed to keep this prospectus effective until the earlier of (i) the date on which the securities may be resold by the selling stockholders without registration and without regard to any volume or manner-of-sale limitations by reason of Rule 144, without the requirement for the Company to be in compliance with the current public information under Rule 144 under the Securities Act or any other rule of similar effect or (ii) all of the securities have been sold pursuant to this prospectus or Rule 144 under the Securities Act or any other rule of similar effect. The resale securities will be sold only through registered or licensed brokers or dealers if required under applicable state securities laws. In addition, in certain states, the resale securities covered hereby may not be sold unless they have been registered or qualified for sale in the applicable state or an exemption from the registration or qualification requirement is available and is complied with.

Under applicable rules and regulations under the Exchange Act, any person engaged in the distribution of the resale securities may not simultaneously engage in market making activities with respect to the common stock for the applicable restricted period, as defined in Regulation M, prior to the commencement of the distribution. In addition, the selling stockholders will be subject to applicable provisions of the Exchange Act and the rules and regulations thereunder, including Regulation M, which may limit the timing of purchases and sales of the common stock by the selling stockholders or any other person. We will make copies of this prospectus available to the selling stockholders and have informed them of the need to deliver a copy of this prospectus to each purchaser at or prior to the time of the sale (including by compliance with Rule 172 under the Securities Act).

The following summary descriptions of our common stock, preferred stock and warrants are based on the provisions of our certificate of incorporation and bylaws, and the applicable provisions of the Delaware General Corporation Law. This information may not be complete in all respects and is qualified in its entirety by reference to the provisions of our certificate of incorporation, bylaws and the Delaware General Corporation Law. For information on how to obtain copies of our certificate of incorporation and bylaws, see the information below under the heading “Where You Can Find Additional Information.”

Our authorized capital stock consists of 100,000,000 shares of common stock, par value $0.0001 per share, and 40,000,000 shares of preferred stock, par value $0.0001 per share, 30,000 of which are designated as Series A Junior Participating Preferred Stock, 18,000 of which are designated Series F Convertible Preferred Stock (the “Series F Preferred Stock”), 100 of which are designated Series F-1 Convertible Preferred Stock, and 600,000 of which are designated Series J Convertible Preferred Stock (the “Series J Convertible Preferred Stock”) as of July 31, 2026. Once shares of Series F Preferred Stock, Series F-1 Preferred Stock, and Series J Preferred Stock are converted, redeemed or reacquired by us, such shares shall resume the status of authorized but unissued shares of undesignated preferred stock.

As of July 31, 2026, we had (i) 1,904,623 outstanding shares of common stock, (ii) 27 outstanding shares of Series F Preferred Stock, which, at the currently applicable conversion price, would convert into 2,592 shares of common stock, subject to future adjustment, (iii) 34 outstanding shares of Series F-1 Preferred Stock, which, at the currently applicable conversion price, would convert into 3,264 shares of common stock, subject to future adjustment, (iv) 159 outstanding shares of Series J Convertible Preferred Stock, which, at the currently applicable conversion price, would convert into 3 shares of common stock, subject to future adjustment, (v) outstanding warrants to purchase 159 shares of Series J Convertible Preferred Stock, (vi) outstanding options to acquire 1,722 shares of our common stock and (vii) outstanding warrants to purchase 932,138 shares of our common stock.

The following description summarizes the most important terms of our capital stock. Because it is only a summary, it does not contain all the information that may be important to you. For a complete description you should refer to our certificate of incorporation, bylaws and certificate of designation of preferences, rights and limitations of Series F Preferred Stock and Series J Preferred Stock, copies of which have been incorporated by reference as exhibits to the registration statement of which this prospectus forms a part, and to the applicable provisions of the Delaware General Corporation Law (the “DGCL”).

Holders of our common stock are entitled to receive dividends when and as declared by our board of directors out of funds legally available.

Holders of our common stock are entitled to one vote for each share on each matter properly submitted to our stockholders for their vote; provided however, that except as otherwise required by law, holders of our common stock will not be entitled to vote on any amendment to our certificate of incorporation (including any certificate of designation filed with respect to any series of preferred stock) that relates solely to the terms of a series of outstanding preferred stock if the holders of such affected series are entitled, either separately or together as a class with the holders of one or more other such series, to vote thereon by law or pursuant to our certificate of incorporation (including any certificate of designation filed with respect to any series of preferred stock).

Subject to the voting restrictions described above, holders of our common stock may adopt, amend or repeal our bylaws and/or alter certain provisions of our certificate of incorporation with the affirmative vote of the holders of at least 66^2∕3% of the voting power of all of the then-outstanding shares of our capital stock entitled to vote generally in the election of directors, voting together as a single class, in addition to any vote of the holders of a class or series of our stock required by law or our certificate of incorporation. Those provisions of our certificate of incorporation that may be altered only by the super-majority vote described above relate to:

Holders of our common stock do not have any conversion, redemption or preemptive rights pursuant to our organizational documents.

In the event of our liquidation, dissolution or winding up, holders of our common stock are entitled to share ratably in any assets remaining after the satisfaction in full of the prior rights of creditors and the aggregate of any liquidation preference pursuant to the terms of any certificate of designations filed with respect to any series of preferred stock, including our outstanding Series F Preferred Stock and Series J Preferred Stock.

Our common stock is listed on the Nasdaq Capital Market under the symbol “NUWE.”

We may issue any class of preferred stock in any series. Our board of directors has the authority to establish and designate series, and to fix the number of shares included in each such series and to determine or alter for each such series, such voting powers, designation, preferences, and relative participating, optional, or other rights and such qualifications, limitations or restrictions thereof. Our board of directors is not restricted in repurchasing or redeeming such stock while there is any arrearage in the payment of dividends or sinking fund installments. Our board of directors is authorized to increase or decrease the number of shares of any series subsequent to the issuance of shares of that series, but not below the number of shares of such series then outstanding. The number of authorized shares of preferred stock may be increased or decreased, but not below the number of shares thereof then outstanding, by the affirmative vote of the holders of a majority of the common stock, without a vote of the holders of the preferred stock, or of any series thereof, unless a vote of any such holders is required pursuant to the terms of any certificate of designation filed with respect to any series of preferred stock.

Prior to issuance of shares of any series of preferred stock, our board of directors is required by Delaware law to adopt resolutions and file a certificate of designation with the Secretary of State of the State of Delaware. The certificate of designation fixes for each class or series the terms, preferences, conversion or other rights, voting powers, restrictions, limitations as to dividends or other distributions, qualifications and terms or conditions of redemption for each class or series. Any shares of preferred stock will, when issued, be fully paid and non-assessable.

As of July 31, 2026, there were warrants outstanding to purchase a total of 932,138 shares of our common stock, which were exercisable at prices ranging from $2.72 to $1,286,250 and are exercisable over a period ranging from immediate to 5.0 years. Certain of these warrants have a net exercise provision under which its holder may, in

lieu of payment of the exercise price in cash, surrender the warrant and receive a net amount of shares based on the fair market value of our common stock at the time of exercise of the warrant after deduction of the aggregate exercise price. Each of these warrants also contains provisions for the adjustment of the exercise price and the

Certain provisions of our certificate of incorporation and bylaws may be considered to have an anti-takeover effect, such as those provisions:

We are also subject to Section 203 of the DGCL, which generally prohibits a Delaware corporation from engaging in any business combination with any interested stockholder for a period of three years following the date that the stockholder became an interested stockholder, unless:

In general, Section 203 defines a “business combination” to include the following:

In general, Section 203 of the DGCL defines an interested stockholder as an entity or person beneficially owning 15% or more of the outstanding voting stock of the corporation and any entity or person affiliated with or controlling or controlled by any of these entities or persons.

The above-summarized provisions of our certificate of incorporation and bylaws and the above-summarized provisions of the DGCL could make it more difficult to acquire us by means of a tender offer, a proxy contest or otherwise, or to remove incumbent officers and directors. These provisions are expected to discourage certain types of coercive takeover practices and takeover bids that our board of directors may consider inadequate and to encourage persons seeking to acquire control of us to first negotiate with our board of directors. We believe that the benefits of increased protection of our ability to negotiate with the proponent of an unfriendly or unsolicited proposal to acquire or restructure us outweigh the disadvantages of discouraging takeover or acquisition proposals because, among other things, negotiation of these proposals could result in an improvement of their terms.

Our Fourth Amended and Restated Certificate of Incorporation, as amended, provides that, unless we consent in writing to the selection of an alternative forum, the Court of Chancery of the State of Delaware will be the exclusive forum for any derivative action or proceeding brought on our behalf; any action asserting a breach of fiduciary duty; any action asserting a claim against us arising pursuant to the DGCL; or any action asserting a claim against us that is governed by the internal affairs doctrine. These provisions would not apply to suits brought to enforce a duty or liability created by the Exchange Act, or any other claim for which the federal courts have exclusive jurisdiction. Our Fourth Amended and Restated Certificate of Incorporation, as amended, will further provide that the federal district courts of the United States of America will be the exclusive forum for resolving any complaint asserting a cause of action arising under the Securities Act, subject to applicable law. Any person or entity purchasing or otherwise acquiring any interest in our securities shall be deemed to have notice of and consented to these provisions. Our exclusive forum provision will not relieve us of our duties to comply with the federal securities laws and the rules and regulations thereunder, and our stockholders will not be deemed to have waived our compliance with these laws, rules and regulations.

The provisions of the DGCL, our Fourth Amended and Restated Certificate of Incorporation, as amended, and our Third Amended and Restated Bylaws, as amended, could have the effect of discouraging others from attempting

hostile takeovers and, as a consequence, they may also inhibit temporary fluctuations in the price of our common stock that often result from actual or rumored hostile takeover attempts. These provisions may also have the effect of preventing changes in our management. It is possible that these provisions could make it more difficult to accomplish transactions that stockholders may otherwise deem to be in their best interests.

Our certificate of incorporation limits the liability of our directors to the fullest extent permitted by Delaware law. Delaware law provides that directors of a corporation will not be personally liable for monetary damages for breach of their fiduciary duties as directors, except for liability for any:

These limitations of liability do not apply to liabilities arising under federal securities laws and do not affect the availability of equitable remedies such as injunctive relief or rescission.

Our bylaws provide that we will indemnify and advance expenses to our directors and officers to the fullest extent permitted by law or, if applicable, pursuant to indemnification agreements. They further provide that we may choose to indemnify our other employees or agents from time to time. Subject to certain exceptions and procedures, our bylaws also require us to advance to any person who was or is a party, or is threatened to be made a party, to any proceeding by reason of the person’s service as one of our directors or officers all expenses incurred by the person in connection with such proceeding.

Section 145(g) of the DGCL and our bylaws also permit us to secure insurance on behalf of any officer, director, employee or other agent for any liability arising out of his or her actions in connection with their services to us, regardless of whether our bylaws permit indemnification. We maintain a directors’ and officers’ liability insurance policy.

We entered into indemnification agreements with each of our directors and executive officers that provide, in general, that we will indemnify them to the fullest extent permitted by law in connection with their service to us or on our behalf and, subject to certain exceptions and procedures, that we will advance to them all expenses that they incur in connection with any proceeding to which they are, or are threatened to be made, a party.

At present, there is no pending litigation or proceeding involving any of our directors or officers as to which indemnification is required or permitted, and we are not aware of any threatened litigation or proceeding that may result in a claim for indemnification.

Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the Company pursuant to the foregoing provisions, or otherwise, the Company has been advised that in the opinion of the SEC this indemnification is against public policy as expressed in the Securities Act and is therefore unenforceable.

The validity of the issuance of the securities offered hereby will be passed upon for us by Honigman LLP, Kalamazoo, Michigan.

Baker Tilly US, LLP, our independent registered public accounting firm, has audited our consolidated financial statements as of and for the years ended December 31, 2025 and 2024 included in our Annual Report on Form 10-K for the year ended December 31, 2025, which are incorporated by reference into this prospectus and elsewhere in the registration statement, and are included in reliance upon such report given on the authority of such firm as experts in accounting and auditing.

We file reports, proxy statements and other information with the SEC in accordance with the Exchange Act. Our reports, proxy statements and other information filed with the SEC are available free of charge to the public over the Internet at the SEC’s website at http://www.sec.gov. These documents may also be accessed on our website at www.nuwellis.com. Information contained in, or accessible through, our website is not a part of this prospectus.

As permitted by SEC rules, this prospectus does not contain all of the information we have included in the registration statement and the accompanying exhibits and schedules we file with the SEC. You may refer to the registration statement, exhibits and schedules for more information about us and the securities. The registration statement, exhibits and schedules are available through the SEC’s website.

SEC rules allow us to “incorporate by reference” into this prospectus much of the information we file with the SEC, which means that we can disclose important information to you by referring you to those publicly available documents. The information that we incorporate by reference into this prospectus, including the consolidated financial statements, is considered to be part of this prospectus. These documents may include Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, as well as proxy statements. You should read the information incorporated by reference because it is an important part of this prospectus.

This prospectus incorporates by reference the documents listed below, other than those documents or the portions of those documents deemed to be furnished and not filed in accordance with SEC rules:

All documents we file with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, except as to any portion of any report or document that is not deemed filed under such provisions, (i) on or after the date of the initial filing of the registration statement containing this prospectus and prior to the effectiveness of the registration statement and (ii) on or after the date of this prospectus until the earlier of the date on which all of the securities registered hereunder have been sold or this prospectus has been withdrawn, shall be deemed incorporated by reference in this prospectus and to be a part of this prospectus from the date of filing of those documents. The information in documents that we file in the future will update and supersede the information currently included and incorporated by reference in this prospectus. Nothing in this prospectus shall be deemed to incorporate information furnished but not filed with the SEC pursuant to Item 2.02 or 7.01 of Form 8-K.

These documents may also be accessed on our website at https://www.nuwellis.com/. Information contained in, or accessible through, our website is not a part of this prospectus.

We will provide without charge to each person, including any beneficial owners, to whom this prospectus is delivered, upon his or her written or oral request, a copy of any or all reports or documents referred to above which have been or may be incorporated by reference into this prospectus but not delivered with this prospectus, excluding exhibits to those reports or documents unless they are specifically incorporated by reference into those documents. You may request a copy of these documents by writing or telephoning us at the following address: