Short answer: Bloomberg Tax and Thomson Reuters CoCounsel Tax are two big tax research platforms with AI built in. CoCounsel Tax publishes its data terms and an entry price. Bloomberg Tax said in March 2025 that its AI comes at no extra charge, but we found no published platform price or AI data policy.
How large firms buy tax AI
Both platforms put AI inside a tax research service, and most plans start with a demo. Thomson Reuters builds CoCounsel Tax on its Checkpoint content, and firms with up to 10 users can also buy its Tax Essentials plan online. Bloomberg Tax adds Bloomberg Tax Answers and an AI Assistant to its research platform.
The data questions are the same as for a small firm. Ask who trains on your data, how long your documents are kept and where they are processed, then get the answers in the contract.
The big platforms
The platforms are listed alphabetically, not ranked.
- Who it's for
- Firms and tax departments that subscribe to the Bloomberg Tax research platform.
- What it does
- Adds Bloomberg Tax Answers and an AI Assistant to the Bloomberg Tax research platform.
- Price as published
- Bloomberg said in March 2025 that its AI features come "at no additional charge" with the platform. We found no published platform price.
- How you buy it
- Request a demo.
- What happens to client data
- We found no published AI data policy, retention period or data location. Will Matthews, Bloomberg Tax's director of product management, quoted in an article on Bloomberg Tax's own site, said: "We do not send information, whether it's your query prompts or now your document uploads outside of our system ... And we never train any LLM with any user information."
Source: Bloomberg Tax AI announcement · Bloomberg Tax research · Will Matthews quote · Checked November 10, 2026
Visit site- Who it's for
- Tax and accounting firms and tax departments that want AI research built on Thomson Reuters' Checkpoint content. The Tax Essentials plan is "designed for mid-market and small CPA tax and accounting firms."
- What it does
- AI built for tax work that gives "citation-backed answers grounded in trusted Checkpoint content." Plans cover tax research, and audit and accounting.
- Price as published
- Tax Essentials: $1,300 a year for one user. CoCounsel Tax Research and CoCounsel Audit & Accounting: price on request.
- How you buy it
- Firms with up to 10 users can buy Tax Essentials online. The other plans start with a demo request.
- What happens to client data
- Thomson Reuters says your content is not used to train CoCounsel's AI features, every call to an outside AI model uses zero retention, and prompts are processed and hosted in the U.S. Your conversations, documents and workspaces are kept for the life of the account unless you delete them.
Source: CoCounsel Tax · CoCounsel Tax plans · CoCounsel Tax pricing · CoCounsel security · Checked November 10, 2026
Visit siteWhat to ask an enterprise vendor
- Is our content used to train your AI, or your model provider's? Thomson Reuters, for example, says your content is not used to train CoCounsel's AI features.
- How long do you keep our conversations and documents? CoCounsel keeps them for the life of the account unless you delete them, though its calls to outside AI models use zero retention.
- Where are our prompts processed and stored? Under the Section 7216 rules, some disclosures to staff outside the United States need the client's consent (Treas. Reg. 301.7216-2(c)).
- Is your AI data policy published, or only described in articles and interviews?
- Will you put your safeguards in the contract, as the FTC Safeguards Rule requires firms to do with service providers (16 CFR 314.4(f))?
Smaller firm?
The tools that fit small and medium firms are on Best AI for small and medium firms. The full ranked list is on the Top AI Tax Tools guide.