What Is a 1099-DA?
The 1099-DA is an information tax form used by brokers/crypto exchanges to report digital asset transactions to both the taxpayer and the IRS. It details transaction specifics such as the asset type (BTC, ETH, etc), the date of the sale, the gross proceeds received as well as the cost basis when available.
Here's the catch for 2025 tax returns: Exchanges are only reporting the digital asset sold, date sold and proceeds received by the taxpayer to the IRS. They are generally not reporting the cost basis and holding period for 2025 transactions. Because the IRS is only seeing the proceeds from the sale of digital assets, if the taxpayer fails to report the correct cost basis and holding period, the tax implications can vary widely, making it more important to ensure you are reporting accurately so you do not overpay.
Why the Numbers on Your 1099-DA Might Look "Wrong"
It is often not that the numbers are 'wrong,' but rather that the exchange lacks the full transaction history required for accurate reporting.
This typically occurs when you purchase an asset on one platform, transfer it to another, or move it to a private wallet before bringing it back to sell.
Because exchanges cannot track your assets once they leave their platform, the cost basis and holding period are often 'reset' to zero or marked as 'unknown' when the asset is moved back. When you move crypto between different environments, the "chain of custody" for tax data is broken.
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.
As mentioned above, the IRS already has a copy of the 1099-DA issued to you. If the figures on your tax return do not align with the data the IRS has on file, it triggers an automated 'income mismatch' flag, likely resulting in a deficiency notice.
To prevent this, you must report the 1099-DA information on Form 8949 and make any necessary adjustments to ensure your final reported gain or loss is accurate.
What Is Form 8949?
Form 8949, Sales and Other Dispositions of Capital Assets, is the line-by-line details where you report every cryptocurrency sale, swap, or exchange.
For every transaction, you must provide the specific asset details, acquisition and sale dates, gross proceeds, and your cost basis. It also serves as the official mechanism for applying adjustments to 1099-DA data, ultimately calculating the final net gain or loss for your return.
For a large volume of activity, you can report summary-level totals for both short-term and long-term. Just use the code to indicate that there are multiple transactions reported in one line.
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.
Short-term transactions reported on Form(s) 1099-DA showing basis was reported to the IRS
Short-term transactions reported on Form(s) 1099-DA showing basis was not reported to the IRS
Short-term digital asset transactions not reported to you on Form 1099-DA or Form 1099-B
Long-term transactions reported on Form(s) 1099-DA showing basis was reported to the IRS
Long-term transactions reported on Form(s) 1099-DA showing basis was not reported to the IRS
Long-term digital asset transactions not reported to you on Form 1099-DA or Form 1099-B
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 | Summary 1099-DA + Exchange name (e.g. “Summary ST 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 = Incorrect Basis · 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
Key Concept
Long-term capital gains typically fall into lower tax rates than short-term capital 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, enter it as short term to be conservative. You're required to account for it, but you'll correct it by backing out the 1099-DA and entering your correct activity.
Where Form 8949 Goes
The data from your Form 8949 flows directly into Schedule D (Capital Gains and Losses). Schedule D acts as a master summary, separating your activity into short-term and long-term totals.
These figures are then combined to calculate your overall capital gains tax liability, which ultimately carries over to Form 1040 to be included in your total tax for the year.
Do You Need Crypto Tax Software?
Yes. If you enter 1099-DA proceeds into your tax software without providing the cost basis, the IRS treats the entire sale as pure profit.
For 2025, many exchanges are reporting gross proceeds but leaving the cost basis blank because they don't have your full history. Without that basis, your tax bill will be based on the full sale price, not your actual gain.
Specialized platforms like Koinly, CoinLedger, or CoinTracking are essential; they sync your entire wallet history to calculate your true cost basis, which you then report on Form 8949 to ensure you only pay what is legally required.
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.
Filing correctly doesn't mean the IRS is done looking.
Most automated crypto audits and CP2000 notices show up months or even years after you file. If the IRS flags something, you don't want to figure out your next move alone. TaxShield monitors your IRS account for red flags and provides full audit defense representation if they ever reach out.
Learn more about Tax Shield