Form 8949
Definition
An IRS form for reporting individual sales and dispositions of capital assets, providing the detailed transaction-level data that feeds into Schedule D.
Form 8949 is the detailed companion to Schedule D. While Schedule D shows summary totals, Form 8949 lists each individual capital asset transaction — every stock sale, crypto trade, or property disposition with its specific dates, proceeds, cost basis, and resulting gain or loss.
The form has two parts mirroring Schedule D: Part I for short-term transactions and Part II for long-term transactions. Each part is further divided by reporting category based on whether the broker reported cost basis to the IRS (Box A, B, or C codes).
Box A covers transactions where cost basis was reported to the IRS (most common for stocks purchased after 2011). Box B is for transactions where cost basis was reported to you but not the IRS. Box C is for transactions with no cost basis reported at all — common for crypto, older stock purchases, and private transactions.
For active traders or crypto users with hundreds or thousands of transactions, Form 8949 can be extremely lengthy. The IRS allows attaching a statement with the same information in lieu of filling out multiple pages of the form, and tax software typically handles this automatically.
The most common errors on Form 8949 involve incorrect cost basis, failing to adjust for wash sales, missing transactions from smaller exchanges, and not accounting for fees in the cost basis calculation.
Where this appears in Clarity
Clarity automatically tracks and calculates these concepts across your connected accounts.
Related Terms
Frequently Asked Questions
Do I need Form 8949 for every trade?
If your 1099-B shows that cost basis was reported to the IRS and no adjustments are needed, you can enter summary totals directly on Schedule D. Otherwise, each transaction needs to be listed on Form 8949.
How do I report crypto on Form 8949?
Each crypto sale, trade, or disposition is a separate line on Form 8949. Report the date acquired, date sold, proceeds, cost basis, and gain/loss. Crypto-to-crypto trades count as dispositions. Most crypto tax software generates Form 8949 automatically.