Byron

Byron is an AI platform that automates business tax preparation, and it stands out for tackling the hard returns, 1065, 1120 and 1120-S, that most tax AI has avoided in favour of simpler 1040 work. It is aimed at CPA firms and comes from a team drawn from Amazon's AGI group and Deloitte, with a $6.5M seed led by Square Peg.

What it does well, on the evidence so far: it targets the genuinely complex parts of business tax, book-to-tax adjustments, depreciation, state apportionment and partnership allocations, each handled by a specialised agent, and automatically rolls prior-year returns and workpapers forward. It processes tricky documents like K-1s and reports over 97% extraction accuracy across federal, state, K-3 and footnotes, and it is SOC 2 Type II compliant with US hosting and no model training on customer data.

Where to be cautious: it launched in May 2026, so independent preparer reviews are still limited, and business tax is high-stakes, so the accuracy claims should be validated on returns you can check. It integrates with existing systems, but confirm the fit with your tax software.

Best for: CPA firms that prepare business returns and want to automate the heavy preparation and workpaper rebuild.

Verdict: one of the more credible new entrants in business tax AI, precisely because it goes after the complex returns rather than the easy ones. Pilot it on known returns, keep preparer review in place, and it could remove a lot of the manual grind from business tax season.