Last updated: October 19, 2026 · Applies to the 2026 tax year (returns filed in 2027)
Your exchange’s Form 1099-DA says one thing, your crypto tax software says another, and your own spreadsheet says a third. Small differences are normal: the form and your records are often measuring slightly different things. The goal is not to make every number identical, but to understand each difference, report the correct figures, and make sure every sale the IRS knows about appears on your return.
Key takeaways
- Most mismatches come from fees, lot selection, transfers, swaps, dates and stablecoin or NFT totals.
- Your return should show the correct numbers, not necessarily the ones printed on the form.
- Fees not reflected on the form are adjusted on Form 8949 with code E; wrong basis with code B.
- A sale missing from your return entirely is what most often triggers an IRS notice.
- Document every difference in a simple reconciliation before you file.
Why the numbers don’t match
| Cause | What you see | Who is right |
|---|---|---|
| Basis missing or incomplete | Box 1g blank or lower than what you paid | Your records, if you can support them |
| Fees treated differently | Proceeds or basis off by small amounts | Usually both; you may need an adjustment |
| Different lots selected | Same proceeds, different basis and holding period | Whichever method was actually applied at the sale |
| Transfers between your accounts | Software shows a sale or a gain the form does not, or vice versa | Neither until the transfer is matched |
| Crypto-to-crypto swaps | Proceeds you don’t recognize, because no dollars changed hands | Usually the form |
| Date and time zone | A sale near midnight on December 31 lands in a different year | The broker’s recorded time, normally |
| Optional totals for stablecoins and NFTs | One aggregate line instead of individual sales | Both; it is the same activity summarized |
| Missing or duplicate forms | Activity you can’t find, or the same sales twice | Ask the broker |
1. Missing or incomplete basis
Brokers only have to report basis for coins acquired after 2025 and held at that broker until the sale. For older coins or coins transferred in, box 1g is often blank. This is the most common mismatch, and we cover it in detail in 1099-DA missing cost basis.
2. Fees
Box 1f shows gross proceeds reduced by transaction costs, so the trading fee on the sale is usually already deducted. Your software might instead show gross proceeds and add the fee elsewhere. Fees on the purchase belong in your basis. If a cost is not reflected on the form, Form 8949 lets you adjust for it with code E in column (f) and a negative amount in column (g). Network (gas) fees paid in crypto can also cause small differences, because paying a fee in crypto is itself a disposal of that crypto.
3. Different lots
If you bought the same coin several times, the broker decides which lots were sold using its default method (often first in, first out) unless you gave it specific instructions at the time of the sale. Your software may be set to a different method, such as highest cost first. The proceeds match, but basis, gain and even short-term versus long-term differ. Your return must follow the lots actually identified at the sale, so align your software with the broker’s method unless you made a timely specific identification. Since 2025, lots are tracked separately in each wallet or account (see wallet-by-wallet cost basis), which also changes the results compared with older “universal” pooling.
4. Transfers between your own accounts
When you move coins from one exchange to another, software sometimes sees only the withdrawal on one side and the deposit on the other. Unmatched, a withdrawal can look like a sale and a deposit like income with zero basis. Match the two sides in your software. A transfer is not taxable, and the coins keep their original purchase date and basis.
5. Crypto-to-crypto swaps
Swapping ETH for SOL is a sale of the ETH. The 1099-DA reports proceeds equal to the dollar value of what you received, even though no dollars hit your bank. People who only track cash withdrawals are often surprised by these lines. They are correct, and they belong on your return.
6. Dates and time zones
Exchanges often record trades in UTC, while software may convert to your local time. A trade on the evening of December 31 in New York is already January 1 in UTC. That can move a sale into a different tax year or change whether a holding period passed one year. Use the broker’s recorded date unless you have evidence it is wrong.
7. Stablecoin and NFT totals
Brokers may report qualifying stablecoin sales and certain NFT sales as a single aggregate line (boxes 11a–11c), or skip them below $10,000 and $600 of proceeds respectively. Your records will show many individual trades where the form shows one total or nothing. You still report the gains or losses, which for stablecoins are usually tiny.
8. Missing, duplicate or corrected forms
Check that each 1099-DA has your correct name and taxpayer ID, covers the right accounts, and is not a duplicate. Brokers can issue corrected forms after the original; if one arrives, use it in place of the first.
How to reconcile, step by step
- Total the form. Add up proceeds (box 1f) and reported basis (box 1g) for each 1099-DA, split into short-term and long-term.
- Total your records for the same broker and the same year, with the same split.
- Compare proceeds first. Proceeds should be close; large gaps point to missing sales, swaps you didn’t track, date differences or duplicates.
- Then compare basis. Differences here are usually missing basis, fees or lot selection.
- Explain every difference in a short note: what it is, which figure is correct and why.
- Fix what can be fixed at the source: match transfers in your software, align the lot method, or ask the broker for a corrected form.
- Report the correct figures on Form 8949, using the right box and adjustment codes.
Worked example: a reconciliation
Daniel’s 1099-DA from one exchange and his crypto tax software show different totals for 2026:
| Form 1099-DA | His software | Difference | |
|---|---|---|---|
| Proceeds | $48,700 | $49,050 | $350 |
| Basis | $21,300 | $39,800 | $18,500 |
| Gain | $27,400 | $9,250 | $18,150 |
He works through the differences:
- Proceeds, $350: his software shows proceeds before trading fees, while box 1f is already net of fees. The form is right; he switches his software to net proceeds. No adjustment needed.
- Basis, $18,500: two sales were of ETH he bought in 2024 on another exchange and transferred in. The form shows no basis for them (box 9 checked); his software has the real $18,500 cost. His records are right; he reports those sales in Form 8949 box K with his basis.
After the reconciliation, Daniel reports proceeds of $48,700, matching the form, and basis of $39,800. His real gain is $8,900, not the $27,400 the form alone would suggest. He keeps the reconciliation note with his tax records.
What if the IRS sends a notice?
The IRS compares information returns with what you file. If proceeds from a 1099-DA do not appear on your return, its automated system can send a notice (often a CP2000) proposing additional tax calculated as if the basis were zero. It is a proposal, not a final bill. Respond by the deadline on the notice with your Form 8949 details and the records that support your basis. A clear reconciliation prepared before filing makes this straightforward, and reporting every sale in the first place usually prevents the notice altogether.
Frequently asked questions
Do my totals have to match the 1099-DA exactly?
No. Your return must be correct. Proceeds usually should match, because the IRS has them. Basis can legitimately differ when the form is blank or wrong, and Form 8949 is designed for that through its boxes and adjustment codes.
Should I wait for a corrected 1099-DA before filing?
If you have asked the broker for a correction and the filing deadline is close, you can file with the correct figures and adjustment codes, or request an extension. An extension gives more time to file, not to pay.
My software and the form disagree on short-term vs long-term. Which wins?
The holding period runs from your actual purchase date. For coins transferred in, the broker may not know that date. Use your records, and make sure your software matched the transfer so the original date carries over.
For the full filing process, see how to report crypto on your taxes, and for what each box means, Form 1099-DA explained.
Sources
- IRS: Instructions for Form 1099-DA
- IRS: Instructions for Form 8949
- IRS: Revenue Procedure 2024-28 (wallet-by-wallet basis)
This article is for educational purposes only and is not tax, legal or investment advice. Tax rules depend on your individual situation; consult a qualified tax professional before filing.