CPA & accounting software, by the numbers

Market share, integration openness, and pricing across the 25 US tax and accounting tools in this guide. Sourced; updated 2026-07-08.

Tax software market share

Usage share among 2,011 US preparers in the 2025 AICPA / Journal of Accountancy tax software survey.

Tax software	Market share (2025 AICPA survey)
UltraTax CS	22.9%
Drake Tax	16.3%
Lacerte	15.8%
CCH Axcess	12.5%
ProSeries	10.5%
ATX	4.6%
ProConnect	3.8%

Integration openness

How the 25 tools break down by how easy they are to connect to:

6 of 25 — Open, self-serve API
7 of 25 — Gated API (approval / plan / partner)
4 of 25 — Zapier only (no direct API)
7 of 25 — No public API (file export)
1 of 25 — No public API yet

FAQ

What tax software has the largest market share?

Thomson Reuters UltraTax CS leads at 22.9% share of surveyed firms, followed by Drake Tax and Intuit Lacerte (2025 AICPA tax software survey).

How many CPA tools offer an open API?

6 of the 25 tools in this guide offer a self-serve public API; 7 have a gated API, and the rest connect only via Zapier or file export.

How this guide works

Most software directories rank by who pays. This one doesn't. It's a plain editorial reference, written to be useful to a working firm rather than to any vendor — including the one that maintains it.

No pay-to-list

No vendor pays for inclusion, placement, or ranking. There is no "sponsored" sort and no paid badges. Every product that meets a category's criteria can appear.

Only shipped capabilities

Each tool is described only by features it has actually released, sourced from the vendor's own product and developer documentation (reviewed July 2026). Roadmap items are not counted.

Categories a firm recognizes

Categories follow how US practices actually evaluate software, each with a stated definition and inclusion criteria. Deadline tracking is treated as a capability of practice management, with a small specialist list called out.

Who maintains it

CPA Field Guide is written and maintained by the team behind DueDateHQ, a deadline-monitoring tool listed in the guide. We describe every product — ours included — by the same standard, and never rank ours above its peers.