Tax AI Built With OpenAI Ran 7,000 Returns at Thrive’s Firms

OpenAI’s account of its forward deployed engineering (FDE) team, published on 22 October 2026, names one customer case with a business model attached. With Thrive Holdings, OpenAI’s FDEs and researchers built Tax AI for Crete’s accounting firms, and “During its pilot, Tax AI processed 7,000 tax returns and increased throughput by about 50%,” the post says.

Thrive Holdings is not a software customer in the usual sense. It buys services businesses such as accounting firms and runs them with AI, and OpenAI took an ownership stake in it in December 2025, TechCrunch reported. OpenAI’s earlier post on the same system, dated 27 May 2026 in OpenAI’s news feed, adds the detail: one senior accountant went from 180 hours of tax prep to 15.

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What OpenAI Says Tax AI Did

OpenAI’s two posts give the figures for the system. The 22 October post repeats the headline numbers; the 27 May post explains how they were measured.

• Volume. “Tax AI processed 7,000 tax returns across the Crete firms that participated in the pilot this tax season,” the May post says. It covers 1040 and 1041 returns.
• Time and output. “It saves practitioners about a third of their time on tax preparation, drafts returns with up to 97% accuracy, and increases throughput by about 50%,” according to the May post.
• Improvement over the season. “At launch, only a quarter of returns were at 75% correct field completion, but within six weeks, 86% hit that mark,” OpenAI wrote.
• The hardest schedule. “Rental properties took about six weeks and substantial engineering oversight to reach 90% precision and recall,” the May post says, and the work carried over to Schedule C and Schedule A.
• One accountant. “One senior accountant who spent 180 hours on tax prep last year spent only 15 hours on it this year,” OpenAI wrote in May.

The starting point was manual work. “For medium- to large-complexity filings, data entry alone can take eight hours per return,” the May post says of Crete’s practitioners.

The Table: Tax AI by the Numbers

Eight figures appear across OpenAI’s two posts and Thrive’s figures as reported by TechCrunch in August.

Each figure is as stated by the named source on the date shown. The 27 May 2026 figures come from OpenAI’s earlier post on the same system; the 22 October 2026 post repeats the 7,000 returns, the throughput and the six weeks. The selection of rows is ours.

Thrive’s August figures and OpenAI’s differ in wording. TechCrunch reported in August, citing Thrive, that the agents processed more than 7,000 tax returns at 98% accuracy and cut tax prep times at participating firms by over 30%, while OpenAI’s May post says “up to 97% accuracy” and about a third of time saved. Neither source says how the two accuracy figures were measured against each other.

How the Loop Works

OpenAI’s May post describes three parts: practitioner feedback, product traces that record each step from source documents to the filed return, and an improvement loop run with Codex.

• Corrections become data. When an accountant changes a value, the system compares Tax AI’s output with the filed return and records the difference at field level.
• Repeated errors become tests. Similar corrections are grouped, and repeated patterns become evaluation targets, the post says.
• Codex proposes the fix. Codex investigates, proposes changes and reruns the tests, and the result goes to engineers for review. “Engineers remain responsible for architecture, product decisions, and shipping,” OpenAI wrote.

The Owner-Operator Model

The structure is what OpenAI’s May post points to. “Holdings is both an owner and operator, so our combined engineering teams are able to work directly with practitioners and production data from inside businesses like Crete, not as a vendor but as partners,” it says.

• Scale. Thrive Holdings raised $2 billion at a $12 billion valuation from investors including SoftBank, D1 Capital Partners and Altimeter Capital, TechCrunch reported on 12 August 2026. It has passed 70 businesses on its platforms, according to the same report.
• The accounting arm. TechCrunch described Current as Thrive’s accounting arm, with more than 50 firms and more than 2,000 professionals. A Business Wire release in June carried the headline “Crete Professionals Alliance Rebrands as Current”; OpenAI’s posts still use the name Crete.
• The OpenAI link. Thrive Holdings is a spinout of Thrive Capital, one of OpenAI’s major investors, TechCrunch reported, and OpenAI took an ownership stake in Thrive Holdings in December 2025. TechCrunch wrote then that the deal would involve OpenAI sending employees from its engineering, research and product teams to work within Thrive’s companies.
• How OpenAI is paid. “If those companies succeed, OpenAI’s stake will grow, and it will get compensated for its services, according to a source familiar with the matter,” TechCrunch reported in December 2025.

The Arithmetic

• About 92% fewer hours for one accountant. From 180 hours to 15 is 165 hours fewer, or about 92%, by our arithmetic. It is one example from OpenAI’s May post, not an average.
• 61 points in six weeks. The share of returns at 75% correct field completion went from a quarter to 86%, a rise of 61 percentage points by our arithmetic.
• Two time-saved figures. “About a third” from OpenAI and “over 30%” in TechCrunch’s report citing Thrive describe the same system in similar terms; we do not combine them.

Connecting the Coverage

• Our piece on AI labs becoming services firms covers the rest of OpenAI’s 22 October post, including the deployment that went from two months to one day, and the services ventures both labs have set up.
• Our piece on AI-linked job cuts covers Reuters’ factbox of about 102,800 announced cuts, by our arithmetic.
• Our piece on Anthropic’s law-firm terms covers Bloomberg Law’s report on professional firms adopting Claude more slowly than they explore it.

The Structural Read

As we read it, the business model is the news. Thrive Holdings owns the firms it automates, so the throughput OpenAI describes accrues to the owner of the work, not to a buyer of software.

As we read it, the corrections are the asset. OpenAI’s May post describes every practitioner edit being recorded as structured data that feeds the next fix, and the operator of the work is the party that sees those edits.

As we read it, OpenAI is tied to the outcome as well as the software. TechCrunch reported, citing a source, that OpenAI’s stake grows if Thrive’s companies succeed.

Three Implications

FOR ACCOUNTING FIRMS OpenAI’s May post puts the starting point at up to eight hours of data entry per medium-to-large return, and says one senior accountant went from 180 hours of tax prep to 15.

FOR SOFTWARE VENDORS Thrive Holdings works “not as a vendor but as partners”, OpenAI wrote, because it owns the firms; that is a different route to the same customers.

FOR AI LABS OpenAI’s 22 October post lists Tax AI among its FDE engagements, and TechCrunch reported in December 2025 that OpenAI would send engineering, research and product staff to work within Thrive’s companies.

The Business Engineer Lens

This story maps onto the Business Engineer framework From SaaS to AGaaS.

The framework says: “SaaS is charged for access to tools. AGaaS charges for the execution of outcomes.”

As we read it, Thrive Holdings takes that a step further by owning the firms that sell the outcome, a filed tax return, and running Tax AI inside them. The framework was published in March 2026 and does not discuss Thrive or Tax AI.

What Is Not Established

The figures are OpenAI’s and Thrive’s own accounts, not independent measurements. The 7,000 returns, the throughput and the accuracy figures come from a pilot at the firms that took part, not from all of Current’s firms. The 180-to-15 hours case is one accountant. OpenAI’s May post does not say how the time savings were measured. The terms of OpenAI’s stake in Thrive Holdings were not disclosed, TechCrunch reported.

We could read only the headline of the Business Wire release on the Current name. The 92% and 61 points are our arithmetic.

More from OpenAI’s FDE post

• AI Labs Become Services Firms as OpenAI Cites 1-Day Rollout
• The ‘Deployment Gap’ OpenAI Built a Team to Close, Explained
• OpenAI Says AI Cut a Chipmaker’s Test-Writing Time by ~48%
• OpenAI’s Voice Model Rose From 60% to 90%+ on Telecom Evals

The Bottom Line

OpenAI’s 22 October post says Tax AI, built with Thrive Holdings for Crete’s accounting firms, processed 7,000 tax returns in its pilot and increased throughput by about 50%. OpenAI’s May post on the same system says it saves practitioners about a third of their time, drafts returns with up to 97% accuracy, and cut one senior accountant’s tax prep from 180 hours to 15. Thrive Holdings owns the firms it runs the system in, and OpenAI took an ownership stake in Thrive Holdings in December 2025, TechCrunch reported.