How It Works

API — point your existing integration at us

The AI industry made this normal: one engine, several API shapes. DeepSeek answers on an OpenAI-compatible endpoint, an Anthropic-compatible endpoint, and its own native API — same model underneath, your choice of interface. xAI and others do the same. You change a base URL, and the code you already wrote just works.

SALTklaw follows that pattern for tax. The same parcel-accurate, statute-bound engine answers on three endpoints:

Taxability — read the law, not a code

The SALTklaw klaw harvester pulls your product master — full product descriptions and ingredients — and, for every administering jurisdiction, assigns taxability bound to the original statute, regulation, or decision that controls it.

Every competitor maps products to an approximation “taxability code,” then tries to harmonize those codes across independent jurisdictions that have completely different statutes — and even different terms for the same thing. That harmonization is interpretation, and interpretation is guessing. Our founder designed that code-based approach two decades ago; the industry still runs on it.

SALTklaw does not harmonize codes. It reads the controlling law for each jurisdiction directly. The only way to do that with complete accuracy is by hand with an LLM — but an LLM that never drifts or hallucinates. Our patent-pending consistent classification system makes the determination deterministic: the same product, the same statute, the same answer, every time — bound to the citation, not a guess.

Calc — the exact parcel, not a point

For each address that governs the transaction — up to five, because sourcing rules decide which one applies — SALTklaw resolves to the actual cadastral parcel. We are not validating an address to deliver mail, and we do not interpolate a latitude/longitude to approximate where the parcel is. Our own extremely fast address standardization and hashing matches the address to the legal definition of the situs.

The industry standard is point-in-polygon: interpolate a point — a guess — then compute which jurisdiction polygon contains it. Our founder designed that too; Avalara still ships it. It breaks in the cases that matter: when a legal boundary runs through a parcel, a single point lands on one side and gets the rate wrong.

SALTklaw is polygon-in-polygon. We test the parcel polygon against the jurisdiction polygon and determine whether the parcel is inside, outside, or bisected — then apply each jurisdiction’s own rule for a bisected parcel. It is the only way to determine situs precisely. This is the cadastral parcel spine, and it is part of the patent. From there the rest is not hard: intersect rules, exemptions, rate — simple math.

Returns — filed and paid from your trust account

A determination and a calculation are worth nothing if the return never gets filed. You fund a trust account with the tax you owe — that money is held in trust, never ours — and we prepare, submit, and pay every return to every administering jurisdiction from it, on schedule. The only money you pay SALTklaw is our service fee; your tax stays yours until it reaches the state.

Self-Audit — harvest, audit, report

Run a self-audit any time. Hand the report to a state auditor and the audit ends — because every line reaches the same answer the state would.