UltraTax CS Review
UltraTax CS is Thomson Reuters' professional tax preparation software for CPA firms, covering individual, business, fiduciary, exempt and estate returns with federal and state e-file, sold as part of the CS Professional Suite.
Independently scored, one dimension at a time. Every dimension is sourced, and we say whether a claim is published, reported, or estimated.
Thomson Reuters lists 1040, 1041, 1120, 1120-C, 1120-S, 706, 709, 990 and 5500 returns plus more than 371 state and local e-file returns, and the help center adds 1065, 2290 and FBAR (checked 4 October 2026). In the JofA 2026 survey, 92.1 percent of users said it had every form they needed, above the 89.8 percent for CCH ProSystem fx and 85.9 percent for CCH Axcess Tax (reported). The 2025 first release on 18 November shipped with preliminary forms, and states arrived from late December through January.
UltraTax CS shares data with Accounting CS, Workpapers CS, Practice CS, Fixed Assets CS, FileCabinet CS, Planner CS, Onvio, GoFileRoom, Checkpoint, SafeSend and SurePrep, and imports from CaseWare, ProSystem fx Engagement and other third-party packages (help center, checked 4 October 2026). Users gave it the top scores for integration (3.4 of 5) and data import (3.5) in the JofA 2026 survey. Most links outside Thomson Reuters are file-path imports, without an API.
UltraTax CS e-files through CS Connect, which asks for confirmation in the Thomson Reuters Authenticator app, and its 2025 release removed email as a two-factor option and tightened master passwords (What's new page, checked 4 October 2026). Advanced security lets admins allow or restrict features by user group, including Tax Automation (help center). Users rated e-file ease 4.6 of 5 in the JofA 2026 survey. No public SOC 1 or SOC 2 report for the hosted options was found, and audit defense comes through Protection Plus, a partner.
The JofA 2026 survey shows use across every firm size: 35.8 percent of 6 to 20 preparer firms and 30.5 percent of firms with more than 500 preparers. Firms run it on their own network or on Thomson Reuters' hosted Virtual Office CS or SaaS, which Thomson Reuters reworked on updated Citrix architecture for the 2024 season (customer letter, May 2024) and has been moving to Azure Virtual Desktop (conversion overview). Capacity planning for a desktop install falls to the firm's IT.
Thomson Reuters runs a Tax Data Conversion Service for the two most recent tax years from CCH Axcess, Lacerte, Drake, GoSystem Tax and ProSeries, usually from July, taking several days per conversion (conversion overview, checked 4 October 2026). Prior-year PINs and AGIs do not convert, and 706, 709, 2290 and 5500 data is out of scope. Training comes as documentation, videos and virtual or on-site instruction from Thomson Reuters professional services.
Thomson Reuters offers phone, email and chat, with technical support weekdays 9am to 8pm ET per its help center widget (checked 4 October 2026). In the JofA 2026 survey, UltraTax CS users rated ease of getting support 3.6 and quality 3.6 of 5, against all-product averages of 3.7 and 3.8, and 34.4 percent named support a top dislike. Drake Tax led on both support measures.
Thomson Reuters documents no MCP server and no public API for UltraTax CS, and the official MCP registry lists none (checked 4 October 2026); its first-party Claude connector, CoCounsel Legal, is a pilot that covers legal work only. In-product AI is Tax Automation, which runs documents through SurePrep 1040SCAN and needs that license (What's new page), plus a generative AI help search. Ready to Review, a separate CoCounsel app for simple 1040s, became generally available on 15 December 2025, and a CoCounsel link from the Print Returns window is listed as coming soon.
The product page says custom pricing depends on users, tax returns and states (checked 4 October 2026). The CS Professional Suite price list, which covers pay-per-return licenses, e-filing and eSignature transmissions, opens only after a customer signs in (help center). In the JofA 2026 survey, 80.5 percent of UltraTax CS users named price a top dislike.
The forms-complete hub of the CS suite, priced behind a login and still closed to outside agents
Written by the Audit Friendly research team. No vendor edits, no sponsored placement.
You are buying the tax engine at the center of Thomson Reuters' CS Professional Suite. UltraTax CS prepares 1040, 1065, 1120, 1120-S, 1041, 990, 706, 709 and 5500 returns and e-files more than 371 state and local returns, according to Thomson Reuters. It was the most used package in the Journal of Accountancy 2026 tax software survey, named by 22.3 percent of 1,808 CPA respondents (reported), and 92.1 percent of its users said it had every form they needed. The value compounds when the firm also runs Accounting CS, Workpapers CS, Practice CS, SafeSend and SurePrep.
The catch is cost and openness. There is no public price: the CS Professional Suite price list sits behind a customer sign-in, and 80.5 percent of UltraTax CS users named price a top dislike in the same survey. Users rated its support 3.6 of 5, below the 3.8 average. It runs as a Windows desktop install or on hosted Virtual Office CS, with no public API, so the AI story depends on buying more Thomson Reuters products: SurePrep 1040SCAN for document extraction and Ready to Review for agent-drafted simple 1040s.
Before signing, get in writing: the full fee schedule for e-file, pay-per-return, eSignature and portal transmissions; the renewal price cap for the next two filing seasons; exactly which states and return modules the quote includes; whether Tax Automation needs a separate 1040SCAN contract; and how long the firm keeps access to prior-year versions and client files if it leaves.
- Firms of 6 to 500+ preparers already on Accounting CS, Workpapers CS or Practice CS that want one client list and data sharing across them.
- Practices with heavy multistate, fiduciary, exempt and estate work that want those forms and state e-file in one package.
- Firms that buy or plan to buy SurePrep and SafeSend and want document intake, preparation and e-sign delivery wired into the tax software.
- Sole preparers on a tight budget: Drake Tax publishes its unlimited single-user Pro package at $2,845 retail for tax year 2026 ($2,695 before 1 December) and is the top choice of solo respondents in the JofA survey.
- Firms that want a browser-based tax engine with a documented developer API for their own automation.
- Teams that want Claude or another AI agent to open client files, enter data or queue e-files in the tax software today.
The jobs a tax team actually hires UltraTax CS for
Jobs, mapped to how finance teams actually buy.
Prepare multistate business returns from one apportionment grid
UltraTax CS uses an apportionment grid for business returns and a multistate allocation grid for Schedule C or K-1 income. Users rated multistate handling 4.1 of 5, level with the all-product average. Thirty-nine survey write-ins across products complained about state returns, so test your heaviest states in a demo.
Push entity data into owner returns without rekeying
Data sharing by tax ID links 1120-S, 1065 and 1041 returns to the related 1040 without manual linking, per Thomson Reuters. Users rated transfers within returns 4.4 of 5, tied for the top score with Drake Tax.
Automate 1040 data entry with SurePrep inside UltraTax
Tax Automation in UltraTax CS 2025 uploads client documents to SurePrep 1040SCAN, lets staff verify extracted data and imports it into the return. Thomson Reuters claims it eliminates 80 percent of manual data entry; that is a vendor claim. It needs a 1040SCAN license.
Run the CS Professional Suite on one client list
UltraTax CS imports general ledger balances from Accounting CS and Workpapers CS, sends invoice events to Practice CS and stores returns in FileCabinet CS or GoFileRoom. Users still rated integration only 3.4 of 5, which led the field because every product scored low.
Deliver returns for e-signature and auto-queue the e-file
From the 2025 release, UltraTax CS can send the client copy to SafeSend at print time and queue the e-file once the SafeSend signature is complete. Both the e-file and the client copy must be created at the same time for this to work.
Watch the same task in each tool
Forget the 40-row feature grid. Pick a finance workflow and see how this tool and its closest peers actually do it, with our verdict on who wins for whom.
Compare on what matters
What it actually costs
Here's what it really costs: published rates where a vendor lists them, aggregated quote data where they don't, plus a path to your own number.
Federal and state modules priced on users, tax returns and states or jurisdictions; e-file transmissions through CS Connect are billed as separate ($) fee items.
Licenses returns on a per-return basis using PRP codes; prices sit on the customer-only CS Professional Suite price list.
E-filing, PRP e-filing, eSignature and client organizer transmissions marked ($) in CS Connect, plus NetClient CS portals for 1040 returns.
SurePrep document extraction inside UltraTax CS; appears for firms licensed for 1040SCAN.
Thomson Reuters-hosted access to UltraTax CS and other CS Professional Suite products.
What it actually takes to go live
Thomson Reuters publishes only that UltraTax CS pricing depends on users, returns and states (product page, checked 4 October 2026). Pay-per-return licenses, e-filing, eSignature and organizer transmissions are priced on the CS Professional Suite price list, which a customer opens from the Renewals tab after signing in. In the JofA 2026 survey, 80.5 percent of users named price a top dislike. Get every per-item fee in the quote.
Thomson Reuters documents no public API for UltraTax CS, and no MCP server appears in the official registry (checked 4 October 2026). Integrations run through file paths set in User Preferences and vendor-to-vendor links such as SurePrep and SafeSend. Thomson Reuters' first-party Claude connector, CoCounsel Legal, covers legal work only. Plan any automation around exported PDFs and reports.
The 2025 What's new page says firms licensed for 1040SCAN get a Tax Automation button that creates binders, verifies extracted data and imports it. Without that SurePrep license, the feature is not there. Ready to Review, the agentic 1040 product launched 15 December 2025, is a separate CoCounsel subscription. Price these alongside the core license.
Thomson Reuters released UltraTax CS 2025 on 18 November 2025 and warned that many first-release forms were preliminary or prior-year versions, recommending only proforma and organizers on it. States started releasing in late December and through January 2026, and data mining usually arrives in the 2025.3.0 update in early to mid February. IRS and states also delay e-file for redesigned forms.
Thomson Reuters' help center says it will stop updates and support for FileCabinet CS after 31 December 2027 and recommends moving documents to another system before then (checked 4 October 2026). UltraTax CS can store returns and client data backups in FileCabinet CS, so the choice affects where returns and 8879s will live. Thomson Reuters documents a migration path to Onvio, and SmartVault, a competing document management vendor, has marketed its own system as the replacement since August 2025.
In the JofA 2026 survey, 76.2 percent of UltraTax CS users needed technical support, and they rated ease of getting it and its quality 3.6 of 5 each, below the 3.7 and 3.8 averages. 34.4 percent named support a top dislike, against 17.7 percent for Drake Tax. Technical support runs weekdays 9am to 8pm ET per the help center widget (checked 4 October 2026); confirm extended hours for filing deadlines.
Scored on what an outside agent can actually reach: the documented API, how it authenticates, and whether the vendor ships an MCP server.
Exists: No. Thomson Reuters publishes no MCP server for UltraTax CS, and the official MCP registry returns no UltraTax or Thomson Reuters tax entry (checked 4 October 2026). Thomson Reuters does run a first-party MCP connector, CoCounsel Legal, but it serves legal research and drafting and does not reach tax returns.
Scope: None for UltraTax data. The integrations Thomson Reuters documents are file-path data sharing across the CS Professional Suite, SurePrep binder export, SafeSend delivery and third-party trial balance imports. A CoCounsel integration that sends printed returns to CoCounsel is listed in the help center as coming soon, with no date.
Turnkey: Not applicable. Any agent work today runs on exports, such as return and diagnostics PDFs and the E-file Status Report in Excel or PDF.
In-product AI: UltraTax CS 2025 added Tax Automation, which uploads client documents to SurePrep 1040SCAN for extraction and imports verified data; it appears for firms licensed for 1040SCAN. Thomson Reuters says its tax automation can eliminate 80 percent of manual data entry and cut return turnaround by 29 percent on average (vendor claim). Ready to Review, a separate CoCounsel app whose agents draft simple 1040s for review, has been generally available in the US since 15 December 2025. A generative AI search sits behind the help icon.
UltraTax CS, kept current
Among 1,808 CPA respondents UltraTax CS kept the top share, slipping from 22.9 percent, while 80.5 percent of its users named price a top dislike.
Thomson Reuters made Ready to Review generally available for 1040 use cases, embedding Gather and Tax Preparer AI agents in the CoCounsel Tax platform.
The 2025 release added Tax Automation with SurePrep 1040SCAN and SafeSend Gather, SafeSend auto-queued e-files, and stricter two-factor and master password rules.
Thomson Reuters unveiled Ready to Review, a CoCounsel-based app whose AI agents draft 1040s for review, in an early adopter program with general availability planned for December 2025.
UltraTax CS was the most used product at 22.9 percent of respondents, up 0.3 percentage point from 2024, per the Journal of Accountancy survey.
UltraTax CS FAQ
Thomson Reuters does not publish a price. The product page says custom pricing is based on the number of users, tax returns, and states and jurisdictions (checked 4 October 2026). Firms choose a full license or a pay-per-return license, and e-filing, eSignature and organizer transmissions marked ($) in CS Connect carry extra fees.
The detailed CS Professional Suite price list opens only after a customer signs in, and no product-specific public benchmark was found. In the JofA 2026 survey, 80.5 percent of UltraTax CS users named price a top dislike. Ask for a written quote by state, return type and transmission, plus the renewal cap.
Thomson Reuters does not publish contract terms for UltraTax CS. Software is released by tax year (the 2025 version shipped 18 November 2025), so ask how long you keep access to prior-year versions and client files after cancelling.
Desktop installs keep client data on the firm network; hosted firms keep it in Virtual Office CS or SaaS. Returns print to PDF, and the E-file Status Report exports to Excel or PDF. Competitors run their own conversion programs, so confirm the target vendor converts UltraTax CS data for the two most recent years before you give notice.
Most firms switch in the off-season. Thomson Reuters' Tax Data Conversion Service converts the two most recent years of 1040, 1065, 1120/1120-S, 1041 and 990 data from CCH Axcess and Lacerte, with narrower coverage from Drake, usually starting in July, and each conversion takes several days.
After conversion, staff review the converted returns, re-enter prior-year PINs and AGIs, set up e-file and add states. Thomson Reuters professional services offers virtual or on-site training. Plan live preparation after the November first release, since Thomson Reuters recommends only proforma and organizers on it.
Not directly. There is no public UltraTax CS API and no MCP server (checked 4 October 2026). Thomson Reuters' first-party Claude connector, CoCounsel Legal, handles legal work only.
Claude can work from exports such as return and diagnostics PDFs and the E-file Status Report to draft review notes and client follow-ups. Inside the Thomson Reuters stack, Tax Automation (with a 1040SCAN license) and the separate Ready to Review app provide AI extraction and agent-drafted simple 1040s.
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