What Is a 1099-DA?
A 1099-DA is a tax form that crypto exchanges send to you and the IRS. It lists the sales or exchanges you made during the year what you sold, the dates, and the prices.
Here's the catch for 2025 tax returns: exchanges are not sending cost basis or total gain columns to the IRS. Only proceeds. The IRS will not get your cost basis numbers or the gain/loss column. That gap is where most of the problems happen and why the numbers can be wildly misleading.
Why Are the Numbers Wrong?
The rules exchanges follow to report your trades are different from the rules you use to file your taxes. Here's the specific problem.
When you transfer a crypto asset into an exchange, the exchange doesn't know when you originally bought it. Under Treasury Regulation 1.6045-1(d), the exchange is required to treat the transfer date as your acquisition date.
So the exchange uses the date the asset arrived not the date you bought it. If you bought Bitcoin in 2023 and transferred it to a new exchange in 2025 before selling, the exchange reports it as a 2025 purchase. That turns a long-term gain into a short-term one and can dramatically increase the tax you owe.
This is also why crypto tax software that promises to match your trades to the 1099-DA is going down the wrong path. The 1099-DA is not the final answer. Even the IRS doesn't assume it's correct.
Can You Ignore the 1099-DA?
No.
The IRS expects you to account for every 1099 they know about. When your return is filed electronically, their system checks whether everything reported to them shows up on your return.
If you skip the 1099-DA, you'll get a notice and possibly a bill for taxes based on the exchange's wrong numbers.
You have to report it. But you also have to correct it. And you do both of those things on Form 8949.
What Is Form 8949?
Form 8949 is called Sales and Other Dispositions of Capital Assets. It's a spreadsheet where you report every crypto sale or exchange what you sold, the dates, proceeds, cost basis, any adjustments, and the net gain or loss.
Dedicated to Short-term gains. This reflects assets held for one year or less before sale.
Dedicated to Long-term gains. This reflects assets held for more than one year before sale.
You can list every individual trade or enter just the bottom-line totals from your crypto tax software. The IRS accepts both. All Form 8949 totals flow to Schedule D, which is where your bottom-line capital gains appear on your tax return.
The exchange reports your proceeds directly to the IRS.
You correct any missing cost basis or errors here.
Total capital gains and losses are summarized here.
Filed with the IRS using accurate and verified numbers.
How to Fix the 1099-DA
Two things need to happen on Form 8949: zero out the wrong numbers from the 1099-DA, then enter your correct capital gains from your crypto tax software. Here's exactly how.
1: Check the Correct Reporting Box
At the top of Form 8949 there's a row of checkboxes. You must check one to indicate whether cost basis was reported to the IRS on a 1099. For digital assets, the relevant boxes are G through L.
Basis reported to IRS on 1099-DA
Basis not reported to IRS
Not reported on a 1099-DA
Basis reported to IRS on 1099-DA
Basis not reported to IRS
Not reported on a 1099-DA
For your 2025 taxes filed in 2026, most crypto traders check Box I (short-term) or Box L (long-term) because no cost basis is being reported to the IRS on the 1099-DA this year. Your 1099-DA will tell you whether transactions are short-term or long-term. Check the matching box.
In future years this will change as cost basis reporting phases in. For now, Box I or L is correct for most situations.
2: Zero Out the 1099-DA Numbers
On the first line of the Form 8949 grid, enter the 1099-DA information and immediately subtract it out so the result is zero. This tells the IRS you reported the 1099-DA but removes the wrong numbers so they don't affect your taxes.
| Col | Field | What to Enter |
|---|---|---|
| A | Description | Exchange name + "1099-DA" (e.g., "Binance 1099-DA") |
| B | Date Acquired | "Various" (standard for multiple purchases) |
| C | Date Sold | "Various" (multiple sales included) |
| D | Proceeds | Total proceeds from the 1099-DA (e.g., $100,000) |
| E | Cost Basis | Leave blank. Exchange doesn't have accurate basis. |
| F | Adjustment Code | BM B = Basis adjusted · M = Multiple transactions |
| G | Adjustment Amount | Negative of proceeds (e.g., -$100,000) |
| H | Gain or Loss | $0. Zeroed out. IRS sees it was reported. |
3: Enter Your Correct Capital Gains
On the next line, enter the actual capital gains you calculated using crypto tax software platforms like Koinly, CoinLedger, or CoinTracking. This replaces the wrong 1099-DA numbers with your real ones.
On the first line of the Form 8949 grid, enter the 1099-DA information and immediately subtract it out so the result is zero. This tells the IRS you reported the 1099-DA but removes the wrong numbers so they don't affect your taxes.
| Column | Field | What to Enter |
|---|---|---|
| A | Description | "Total short-term digital assets (reconciled)" or long-term |
| B | Date Acquired | "Various" |
| C | Date Sold | "Various" |
| D | Proceeds | Your total proceeds from crypto tax software |
| E | Cost Basis | Your total cost basis from crypto tax software |
| F | Adjustment Code | M Summary of multiple transactions. |
| G | Adjustment Amount | None needed on this line |
| H | Gain or Loss | Your actual capital gain or loss |
That's the full correction. The IRS sees the 1099-DA was accounted for on line 1. Your actual gains on line 2 are calculated from your real trading history not the exchange's guess.
Short-Term vs. Long-Term
Long-term capital gains are taxed at a significantly lower rate than short-term gains. Long-term means you held the asset for more than 365 days.
This is the core problem with 1099-DAs. If the exchange uses your transfer date as the acquisition date, it classifies a multi-year holding as a holding of just a few weeks or months and short-term rates apply. You pay more tax than you owe.
If the 1099-DA doesn't reflect your actual holding period, don't report it that way. You're required to account for it but you correct it on Form 8949. That's the entire point of this process.
Where Form 8949 Goes
All your Form 8949 pages get totaled and flow to Schedule D. That's where your bottom-line capital gains are calculated. Short-term totals go to one section, long-term to another. Schedule D combines them into your total capital gains tax liability, which flows to your Form 1040.
Do You Need Crypto Tax Software?
Yes. If you plug 1099-DA numbers straight into your tax software without cost basis, everything looks like pure profit and your bill will be enormous. Without cost basis, the software has no way to calculate your actual gain.
Platforms like Koinly, CoinLedger, and CoinTracking can pull in your full transaction history and calculate actual cost basis and gains. You then take those numbers and enter them on Form 8949 as shown above.
If the whole thing feels overwhelming, that's normal. This is the first year of 1099-DA reporting and the rules are new for everyone including the exchanges issuing them.
Worried your 1099-DA is wrong?
We specialize in complex crypto tax situations missing records, multi-exchange histories, DeFi activity. If it's a mess, we've seen worse.
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