Citi has launched Citi Commerce Media, a media platform that uses transaction data from its U.S. credit card customers to connect brands with consumers across Citi's digital properties, according to a company statement.

The platform draws on data from more than 70 million U.S. customers and 6.5 billion annual transactions across more than 700 spending categories. It is designed to allow advertisers to target audiences based on purchase behavior and measure campaign outcomes through closed-loop attribution.

The platform spans Citi.com, the Citi Mobile app, and paid media properties. Core capabilities include audience identification using first-party transaction data, paid media placements, and measurement tools that track return on ad spend and incremental impact.

Citi said initial campaigns in retail, payments, technology, and beauty and wellness categories showed results including up to 5x incremental return on ad spend for one online retailer.

The launch follows Citi's agreement to acquire Kard, a commerce media and rewards platform. Citi said the planned addition of Kard is intended to expand the platform's capabilities, though the acquisition has not yet closed.

"By leveraging Citi's scale, transaction insights and measurement capabilities, we can help our partners better anticipate consumer needs, reach the right audience at the right moment and drive strong business outcomes while delivering more relevant offers and ads for customers," said Abhinav Anand, Citi's Head of Value Cards, Lending and Commerce.