Thrive Holdings to Spend $1 Billion Acquiring Nearly 50 Local Accounting Firms and Deploying AI Tax Tools

Thrive Holdings plans to invest $1 billion acquiring local accounting practices and integrating artificial intelligence into their operations, the company’s executives told Forbes. The commitment follows the purchase of nearly 50 firms over two years, including a stake in Larson Gross acquired through its subsidiary Current in 2025.

Larson Gross began as a single-office practice founded by Ted Larson in Bellingham, Washington, in 1949.

It expanded to five offices, 200 employees and tens of millions in annual revenue before the 2025 transaction. Thrive Holdings, a spinoff of Joshua Kushner’s Thrive Capital Management, structures its investments to retain minority stakes with local partners and hold positions for extended periods.

At Larson Gross, Thrive Holdings embedded engineers from Ramp, Clay and Databricks alongside firm staff to develop Tax AI.

OpenAI supplied a dedicated team that trained AI agents on tax workflows. During the most recent tax season the platform processed 7,000 returns, delivering an average 31 percent reduction in accountant time and up to 98 percent accuracy in data entry, compared with the typical 10-to-15 percent manual error rate.

One accountant reduced preparation time from 180 hours the previous year to 15 hours.

Tax director Tanya Silves, who has worked at the firm for 25 years, recalled a team member saying the rollout decision initially prompted skepticism but proved correct. Current CEO Steve Stagner, formerly CEO of Mattress Firm, applies an operational standard he calls the Triad: any technology must benefit the client, the employee and the company’s bottom line.

“We aren’t here to run their business,” Stagner said.

The teams have automated self-correction loops so AI agents revise their own processes after human feedback. Over one weekend, OpenAI engineers ran Codex uninterrupted for 48 hours to test hundreds of solutions. “A year ago that would have taken us months to do,” said Arnaud Fournier, chief technology officer of OpenAI’s Deployment Company.

The number of CPA candidates fell 30 percent between 2016 and 2021, according to the Association of Certified Professional Accountants. This summer’s interns at Larson Gross will be trained to review tax returns rather than prepare them. Silves noted that new staff now reach client-facing work faster than she did after 25 years at the firm.