The deal, announced in a statement Monday that confirmed an earlier Bloomberg News report, will bolster Intuit’s offerings for businesses looking for ways to reach and serve customers online. Intuit has offered QuickBooks accounting software to clients for decades, supplementing it with services such as Credit Karma, which it acquired last year.

By adding Mailchimp, Intuit is looking to build on a small-business recovery that has helped fuel sales of QuickBooks and other products. With customers getting operations back on track after Covid-19 disruptions—and many digitizing their books for the first time—Intuit has been able to capitalize. Mailchimp is focused on digital marketing services, including social advertising, so-called shoppable links and automation products.

“Expanding our platform to be at the center of small and mid-market business growth helps them overcome their most important financial challenges,” Intuit Chief Executive Officer Sasan Goodarzi said in the statement.

The planned transaction marks Intuit’s largest deal to date, according to data compiled by Bloomberg. Mountain View, California-based Intuit paid $7.1 billion last year for Credit Karma, a personal finance website.

Intuit was founded in 1983 by Scott Cook and Tom Proulx and went public a decade later. Its TurboTax product has become synonymous with online tax filing, but small-business services account for a larger part of Intuit’s business —and don’t suffer the same seasonal swings.

Atlanta-based Mailchimp traces its origins to a web design agency called the Rocket Science Group, which was founded in 2001 by Ben Chestnut and Dan Kurzius. In January, Mailchimp acquired SMS marketing platform Chatitive Inc., which allows two-way personalized communication between businesses and their customers.

The deal represents a windfall for Chestnut and Kurzius. The company has no outside funding or venture capital backing, according to data provider PitchBook.

The acquisition is expected to close before the end of Intuit’s fiscal second quarter of 2022, and to add to adjusted earnings per share for the full fiscal year, which ends in July. The company said it plans to finance the cash portion of the deal through cash on hand and new debt of approximately $4.5 billion to $5 billion.

Intuit shares fell 1.8% to $557.42 in New York before the announcement. The stock has gained 47% this year, giving the company a market value of $152.2 billion.

Morgan Stanley & Co. acted as financial adviser to Intuit on the deal, while Latham & Watkins LLP is its legal adviser. Mailchimp was advised by Qatalyst Partners and King & Spalding LLP.

—With assistance from Kiel Porter.