Cost Basis Tracker

Track every improvement; pay less tax at sale.

Enter what you paid for your home, the major improvements you’ve made, and what you might sell for. We’ll estimate your profit, how much of it is tax-free, and how much tax your improvement records could save you.

Your basis is what you’ve put in
Your starts with the purchase price plus some closing costs. Every capital improvement (a new roof, a remodel) adds to it. Repairs and upkeep don’t.
Profit is measured against basis
When you sell, your profit (the “gain”) is the sale price minus selling costs minus your basis. A higher basis means a smaller gain, and less of it can be taxed.
Up to $250,000 of gain can be tax-free ($500,000 if married)
The lets you skip tax on up to $250,000 of gain ($500,000 married filing jointly). Only gain above that is taxed, at rates.

Your purchase Closing Disclosure (or HUD-1) shows closing costs. Old invoices, permits, and bank or card statements can rebuild improvement costs. The cost basis tracking guide lists what counts and what records to keep.

Your purchase and sale

What you paid when you bought, and a rough guess at what you’d sell for. You can update the sale price as the market moves.

Purchase price

Closing costs at purchase

Estimated sale price

Selling costs

% of price

Your tax situation

Used only for the gain above the tax-free exclusion. Your last tax return shows your bracket.

Filing status

Federal tax bracket

State income tax rate

Investment tax (NIIT)?

Applies if income is over $200k single or $250k married.

Improvements you’ve made (saved in this browser)

Total capital improvements$71,000

Tax saved by tracking improvements

Your estimated gain ($361,000) fits within the tax-free home-sale exclusion, so no tax is owed at this sale price whether or not you track improvements. Keep tracking anyway: a higher sale price or renting the home out would bring basis back into play.

What you paid

$405,000

$400,000 price + $5,000 closing costs

Improvements logged

$71,000

3 items

Adjusted cost basis

$476,000

what you paid + improvements

Estimated profit (gain)

$361,000

$837,000 after selling costs − $476,000 basis

Tax-free home-sale exclusion

$361,000

up to $500,000 (married filing jointly); covers it all

Estimated tax owed

none: the exclusion covers the gain

What this means

Selling for $900,000 and paying about $63,000 in selling costs leaves $837,000. Subtract your $476,000 adjusted basis and your profit is $361,000. Filing jointly, up to $500,000 of profit is tax-free, so you’d owe nothing, with $139,000 of room to spare.

The tax-free amount assumes you owned the home and lived in it for at least 2 of the 5 years before selling. See capital gains on a home sale for the rules.

What counts (and what doesn’t)

Under the (IRS regulation ), a capital improvement is one that betters the property (makes it more valuable), adapts it for a new use, or restores a major component.

Improvements include a kitchen or bathroom remodel, room addition, new roof, new heating and cooling system, new water heater, replacing major appliances or systems, finished basement, deck or patio addition, pool, solar (cost after the tax credit), permanent landscaping and hardscape, foundation work, replacing the electrical or plumbing system.

Repairs and maintenance don’t count: patching a roof instead of replacing it, painting inside or out, fixing a leaky faucet, replacing a broken appliance with a similar one, cleaning, lawn care, pest control, ongoing service contracts.

A series of repairs that together replace a major component (a roof patched repeatedly until it’s equivalent to a replacement) can become an improvement. Get a CPA’s opinion on cumulative cases.

Save receipts, invoices, permits, before-and-after photos, and cancelled checks. The IRS can generally audit a return for 3 years after you file the return reporting the sale (6 years if you under-report gross income by more than 25%). Keep records at least that long after the sale year; longer is better.

This tool assumes the home has always been your main residence. If it was ever a rental, your basis is reduced by the taken (or “allowable,” even if you forgot to claim it). That depreciation is taxed back at sale at up to 25% federal (under ), and the home-sale exclusion doesn’t cover it. Use the rental tax shelter calculator for that scenario.

See the full cost basis tracking guide for examples and edge cases. Tax law depends on your specific facts, so consult a CPA for homes with large improvements ($150,000 or more) or rental conversions.

Results are estimates based on your inputs and the assumptions on this page, not quotes or advice. A lender, servicer, or tax advisor will give you different numbers. Disclaimer

Something look off? Report it

Terms used on this page

Whether you owe tax on a home sale comes down to the IRS terms below.

Cost basis: What the IRS counts as your investment in the home: the purchase price, plus certain closing costs, plus capital improvements. A higher basis means a smaller taxable gain. More
Adjusted basis: Your basis after adding improvements (and, for a rental, subtracting depreciation). It’s the number your sale price is measured against.
Capital improvement: Work that betters the home, adapts it to a new use, or restores a major part of it, like a remodel or a new roof. Repairs and routine upkeep don’t count.
Gain (profit): Sale price minus selling costs minus your adjusted basis. Only gain above the home-sale exclusion is taxed.
Section 121 exclusion: Lets you skip tax on up to $250,000 of gain ($500,000 married filing jointly) when you sell your main home, if you owned and lived in it for at least 2 of the 5 years before the sale. More
Long-term capital gains rate: The lower federal rate (0%, 15%, or 20%, depending on income) on profit from something you owned more than a year.
NIIT (net investment income tax): An extra 3.8% federal tax on investment income, including taxable home-sale gain, when modified AGI is above $200,000 single or $250,000 married filing jointly. More
Depreciation recapture: If the home was ever a rental, the depreciation you took (or could have taken) is taxed at sale at up to 25% federal, and the home-sale exclusion doesn’t cover it.

Keep learning

Next steps

Capital gains calculator: the full tax picture on a home sale
Seller net sheet: cash you’d walk away with after a sale
Sell vs rent out: whether to sell now or keep it as a rental
Energy credits: credits that also change your basis