Guides · Tax year 2026

Capital gains tax guides

One page per question, each with a worked example computed by the same engine that powers the calculator. No page here restates another: if two questions have the same answer, they share a page.

Tax year 2026 figures. Last updated .

Rates and amounts

What the tax actually costs, which ladder applies, and what changed for 2026.

Working it out, and when to pay

The order of operations, the federal layer end to end, the deadlines, and the levers that legitimately move the number.

Property and real estate

Three property types taxed three different ways, and the exclusion that covers most home sales entirely.

How these pages are written

Every worked example is generated from the engine at build time rather than typed in. When the tax data changes, the examples change with it, so a figure in the prose cannot drift away from the figure the calculator produces.

Every page states its sources. Federal figures come from IRS Revenue Procedure 2025-32 and the Internal Revenue Code; state figures come from each state's own code or revenue department. Nothing is filled in from memory, and where a figure cannot be verified the engine refuses to compute with it rather than guessing — see the methodology.

The pages are also checked against each other. A test measures the pairwise overlap between every pair of guides and fails the build if any two drift toward saying the same thing, because eleven near-identical pages would be worse than the one page they came from.

Looking for your state?

These guides cover the federal layer, which applies wherever you live. The state comparison sets out how each covered state treats a gain on top of it.