Amazon US seller tax prep in 6 steps: get the books clean before you optimize

A lot of US-based Amazon sellers walk into tax season with just a 1099-K in hand. They end up either overpaying or filing wrong — sometimes both.

The better order of operations: get the profit numbers right first, then talk about how to legally reduce the bill.

The 6 steps we run, in order

1. Treat the 1099-K as a reconciliation pointer — not a final answer. It’s a gross payouts number from a narrow definition. Your tax return is not supposed to match it line-for-line.
2. Break Amazon revenue into real buckets. Gross sales, refunds, platform fees, ads, logistics, software, CPA/legal. A single “Amazon income” line is how money leaks.
3. Lock an inventory and COGS method and stay with it. Don’t use one approach this year and a different one next year — the year-over-year deltas become untrustworthy and the CPA’s hands get tied.
4. Check whether you’re eligible for QBI, a self-employed retirement plan, health insurance deduction, and SE tax deduction. Most sellers we audit are leaving at least one of these on the table.
5. If your revenue is seasonal, stop averaging quarterly estimated payments. Mechanically even payments on a lumpy revenue curve create either large shortfalls or large overpayments.
6. Start closing the books monthly and reviewing them quarterly. Don’t discover your 2026 structure from the 2026 1099-K.

Where tooling actually helps

The stack we recommend isn’t fancy. It’s an automation layer for pulling Amazon settlements, ad invoices, SaaS, and logistics into a single reconcilable source of truth — then handing that cleaned record to the CPA for judgment. QuickBooks Intuit Intelligence, Xero JAX, and Avalara each have a role; none of them replace the CPA.

One-liner

Clean the books first. Strategy comes second. If you flip the order, the strategy runs on bad numbers.