How we check the rules

A return is only as good as the rates and rules behind it. Here is how Pinrates keeps them right, and how you can check our work.

• Every rule starts from the state's own source. Each rate and rule in Pinrates carries the citation it came from: the statute, the agency's publication, the rate schedule. On every return and shipment check, that source is one click away.
• Rates come from the states' files, with their dates. Where a state publishes rate and boundary files, as the Streamlined Sales Tax states and California's district taxes do, we load them as published. Each rate keeps the dates it was in force, so an order is taxed at the rate in effect on the day it was sold.
• A rule is reviewed before it applies. A new shipping rule, like a permit requirement or a volume limit, is drafted from its source, checked against it, and published before it applies to any order. Until then it has no effect.
• We test against returns already filed. Before we rely on a state's figures, we recalculate returns already filed there, order by order, and work through every difference.
• When information is missing, we say so. If Pinrates can't settle something, like an address it can't place or a wine without an alcohol content, it tells you what it needs instead of filling in a default.
• Nothing is overwritten. A correction is a new, dated version. Every shipment check and return is saved with the rules and rates it used, so you can show an auditor exactly what happened years later.

When we recalculated a year of a California winery's returns, our tax due matched the filed returns to the dollar ($0 difference).