Byron

Almost every AI tax tool on the market is chasing the 1040. Byron is not. It handles 1065, 1120 and 1120-S returns, and the centre of gravity is the work that actually consumes partnership and S-corp season: reading inbound K-1 packets in whatever format they arrive, including state K-1s, K-3s, footnotes, supplemental statements and partner grids, then extracting line items and allocations and grouping related forms across pages. Around that sits trial balance mapping, book-to-tax reconciliation, same-as-last-year workpaper carryforward and Excel workbooks with two-way sync, each value carrying a source link and a confidence score so a reviewer can approve or reject at the line rather than re-reading the packet.

That focus is the reason to look at it. K-1 rekeying is one of the few remaining tasks where firms still put a body on a chair for weeks, and a tool that reads a scanned partnership packet correctly saves real hours. The security posture is more mature than the company's age suggests: SOC 2 Type II with annual audits, AES-256 at rest and TLS 1.3 in transit on AWS with KMS key management, US-only hosting, US-based personnel with background checks, annual third-party penetration testing, and a stated position that the design does not require an IRC Section 7216 consent because data does not leave the firm's control. Offboarding includes data return in a standard format and a certificate of destruction.

The gaps are large and they are the ordinary gaps of a company this new. Byron launched publicly in May 2026 and has raised a seed round reported at $6.5 million and later $9.1 million led by Square Peg. That means it has not yet been through a full partnership filing season as a shipping product. It names no customer firms, publishes no case study, and posts no busy season numbers. It publishes no price. Most importantly for a category where this is the deciding question, it does not name a single tax engine. The marketing says finished output is pushed into the tax engine the firm already uses and that filing happens where it happens today, but the named integrations are Canopy and Truss, both practice management rather than compliance software. Output is described as Excel workpapers plus approved tax software output, which reads more like a structured file than a direct write-back. And although Byron extracts K-1s, nothing on the site covers distributing finished K-1s out to partners, which is the other half of that workflow.

K1x is the obvious comparison and it is a more established one, built specifically around K-1 ingestion and distribution with years of institutional use behind it. Tallyfor overlaps on book-to-tax and trial balance work. Against both, Byron is the newer and broader product, and the only evidence for it is the demo.

One-to-watch, unambiguously. The entity focus is genuinely differentiated in a field crowded with 1040 tools, the security work has been done properly, and the founding team's Deloitte and Amazon background is a reasonable credential. None of that substitutes for a filing season. A firm should pilot this on a handful of returns rather than plan a season around it.