01 · INGESTION
01The Standard
Engineered for complexity.PARTNERSHIPTAX AUTOMATIONAT SCALE.
Crimson Tree Software helps elite tax teams deliver enterprise-scale partnership reporting with deterministic calculations, AI-led digital operations, and traceable review from trial balance to tax return.

02The Moat
THE DETERMINISTIC ENGINE.Operated by AI.
Generalist AI wrappers extract data and guess at the math. TIERS is different. We isolate the generative AI from the calculation core, ensuring that 1065s, K-1s and K-3s are driven by uncompromising logic.
02 · CALCULATION
Deterministic allocation and tiering across all entities and investors
03 · REASONING
AI reasons and explains with logic backed by data and tax allocation source-code awareness
04 · OUTPUT
Schema-correct 1065 e-file XML generated
03Auditability
THE BURDEN OF PROOF.Every output, traceable to source.
An answer without data-backed explanation is a professional liability. Examine any output data point to see its provenance. Source documents, data points, and the full allocation trail. The glass-box approach to partnership tax. Nothing hidden. Nothing magical.

Overview · 5 areas
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04The house
Precision engineering.HARD PROBLEMS.REAL HISTORY.
Crimson Tree Software has built partnership tax infrastructure since 2001. Not as a venture-backed SaaS startup, but as a precision engineering team. We solved the underlying algebra of Subchapter K that other firms walk away from.
The engines we have built sit behind the firewalls of the Big 4 and Next 10 accounting firms. They acquired them. They run their global practices on them. Today, we operate our flagship platform, TIERS, at enterprise scale.
$2B+
In recurring annual professional fees
Processed through CTS-built systems
We've seen Crimson Tree build and deliver at every level of complexity, for the most demanding clients in the industry. The technology is exceptional. The team has a track record unlike anyone else in this space.
With TIERS and an embedded AI operator, Crimson Tree is leading the next leap — applying their hardened engineering rigor to AI-native partnership tax while preserving the auditability this industry demands.
My team and I searched far and wide for the best technology partner to collaborate on [PartnerSight] with us. The platform we built with Crimson Tree is a differentiator for our clients in the private equity, family office, hedge fund and real estate markets.
TIERS gives our team the ability to take on engagements that simply weren't possible before; structures too complex, timelines too tight, for any labor-intensive approach. We can now compete and win work that most firms can't touch.
05Core capabilities
CORE CAPABILITIES.The complete tax lifecycle.
Three signature interactions from the TIERS platform. The full demo library lives one click below.
VISUAL
Dynamic Organization Chart
Map any partnership structure - tiered funds, GP/LP layers, foreign blockers - in a single living diagram. Click any node to drill into its allocations.
REVIEW
K-1 Comparisons
Year-over-year delta on every box, every partner. Reviewer co-pilot explains the why behind every change.
SALT
State Apportionment Matrix
All 50 states, every method, every nexus standard. Federal and state allocations computed in a single pass.
06End to end
FROM TRIAL BALANCE to tax return.
07Custom solutions
BEYOND TIERS: custom systems for hard problems.
TIERS is what we run today. It is not the only thing we build. For two decades, CTS has been hired to solve the engineering bottlenecks that off-the-shelf software cannot touch. We build tax calculation libraries and AI-native data ingestion engines used by top global firms.
The same engineering principles. The same elite team. Applied where the problem is complex enough to demand our attention.
Our Work →