Partnertax AI - 2026 Pricing, Features, Reviews & Alternatives

PartnertaxAI — the AI tax assistant built for complex questions

PartnertaxAI is an AI research assistant for tax professionals who work on the questions that don't have easy answers. The answer comes from the law itself — the Internal Revenue Code, Treasury regulations, rulings, state statutes, and treaties — with clickable citations to the exact authority, a grounding level on every answer, and a downloadable memo when you need something to put in the file.

The subject matter tax pros bring to it:

State nexus & multistate — remote hires, economic nexus thresholds, P.L. 86-272 protection, franchise versus income tax, weighed state by state across all 50. A dedicated State Tax Matrix lets you compare income tax and sales-and-use tax treatment across states side by side.

Ownership changes & transactions — sales, redemptions, contributions, and reorganizations, with the basis and loss-limitation math that follows: §754 step-ups, §743(b) adjustments, §382 limitations, whatever the structure.

Alternative investments — wash sales, §475(f) mark-to-market elections, §1256 futures and options, swaps, straddles, short sales, and carried interest. PartnertaxAI was built by a founder with a decade in alternative-investment tax compliance.

Cross-border transactions — inbound and outbound: treaty positions, §367 transfers, GILTI and Subpart F, FIRPTA, and PFICs.

Entity formation & elections — choice-of-entity analysis, check-the-box classification, S elections and late-election relief, §83(b), and state of formation, plus a free Taxflows library that generates the actual election and letter documents.

Foreign & state withholding — §1441–1446 withholding on foreign payees and partners, W-8 and W-9 determinations, and state nonresident and composite withholding: who withholds, how much, on which form.

Context that stays put. Every client entity lives in its own silo. Documents, standing facts, and chat memory stay walled off per client — nothing blends across engagements. Set an entity's facts once (structure, states, year, elections) and every future question is answered with that context already in place, instead of retyping the fact pattern into a chat window each time.

Your documents and books, in the conversation. Upload returns, agreements, and workbooks and the assistant reads them alongside your question; redacted copies are available for download. Connect QuickBooks or Xero and ask questions with the accounting data in context — no exports.

A free public library of tax Q&As, practitioner templates, and tools (like a which-W-8 selector) is available without a login.

Security & trust. PartnertaxAI is engineered around the SOC 2 Trust Services Criteria and committed to achieving SOC 2 Type II compliance. Data is encrypted in transit and at rest, access is role-based, and client data is never used to train models. Privacy practices align with CCPA/CPRA, IRC §7216 obligations, and your WISP.

Who it's for. CPAs, EAs, and tax attorneys in firms of any size; in-house tax teams; and fund administrators — anyone whose day includes questions that end in "…and which authority says so?"

Start with free tier — no credit card required.