Your cost basis is the original purchase price of your crypto plus any transaction fees, and it determines your capital gains/losses. Where you track it is entirely up to you. If you mostly trade on Coinbase, tracking it here may be simplest. If you trade across multiple exchanges, wallets, or networks, crypto tax software can help bring your records together.
Depending on when and how you acquired your crypto, Coinbase may not have your original purchase records. You can add that information in the Coinbase Tax Center yourself. This step is optional.
What changes if you update your cost basis
Your Tax Center dashboard: Your estimated gains and losses reflect the cost basis you provide, so they show your historical performance.
Your copy of Form 1099-DA: The cost basis you provide prints on the Recipient Copy, which you can use as a reference when you file.
What does not change if you update your cost basis
The IRS copy of Form 1099-DA: By law, any cost basis you manually provide is classified as noncovered. Coinbase does not send it to the IRS. We report only your gross sale proceeds.
Your filing responsibility: Whether you use this tool or a personal spreadsheet, you are legally required to calculate and report your own cost basis and capital gains on IRS Form 8949 and Schedule D.
Covered and noncovered assets
While Coinbase reported your gross sale proceeds on Form 1099-DA for the 2025 tax year, for tax year 2026 the IRS requires brokers, like Coinbase, to also track and report cost basis for assets acquired in 2026.
Covered assets
You acquire the asset on Coinbase on or after January 1, 2026, and continuously hold on Coinbase until sold. Coinbase tracks your cost basis and reports both your cost basis and sale proceeds to the IRS on Form 1099-DA.
Noncovered assets
The IRS does not require Coinbase to report cost basis for these. This applies to:
Any crypto asset you acquired before January 1, 2026.
Any crypto asset you transfer into Coinbase from an external wallet or another exchange, whenever you acquired it, because we do not have the original purchase records.
For noncovered assets, Coinbase will report your sale proceeds to the IRS on Form 1099-DA, and the cost basis box will be blank and marked noncovered.
How transfers affect your cost basis
Crypto from an external source
When you transfer crypto into Coinbase from a personal wallet or another exchange, we do not know what you paid for it. Your cost basis shows as "Unknown" in the Tax Center. If you sell, Coinbase will use the date you deposited as the default for lot selection (HIFO/LIFO/FIFO). Use your actual purchase date and price when you file so you determine short-term and long-term gains correctly.
Crypto sent to an external address
When you send crypto from Coinbase to an external wallet, we don’t know whether you sent it to yourself or someone else. Moving property between your own wallets is not a taxable event, so we assume you still own it. The transfer is not a reportable sale, and does not generate a Form 1099-DA.
Add missing cost basis
Each transfer can hold more than one lot. For example, if you bought 1 BTC in ten separate purchases of 0.1 BTC over two years and then moved it to Coinbase in one transfer, you can add ten lots in the Tax Center so every purchase date and price is recorded accurately.
To add missing cost basis:
Go to the Add transaction details page in your Tax Center.
In the Needs review tab, select the transaction.
Select Add details.
If the transfer has multiple lots, select Split this transfer and add as many lots as you need.
Enter the date acquired and your total cost basis, including fees.
Select Save.
To edit a cost basis entry you already added:
Go to the Add transaction details page.
In the Modified tab, select the transaction.
Select Edit and update the details.
Select Save.
Coinbase doesn't provide tax advice. Information here is provided to help understand your taxes, but should be reviewed before you file your taxes. Talk to a tax professional to be sure it applies to you.
Related articles