Crypto Tax Hub • 1099-DA Mismatch Help • Missing Cost Basis & Wallet Transfer Issues
Crypto 1099-DA Mismatch Checker
Check missing cost basis, zero basis, wallet‑transfer gaps, exchange mismatches and crypto tax software differences before relying on your crypto tax form.
The IRS’s new Form 1099‑DA applies to digital‑asset sales and exchanges on or after January 1, 2025. For these transactions the form reports the gross proceeds of the sale; cost basis reporting will be required only for covered digital assets involved in sales on or after January 1, 2026. Non‑covered digital assets – including assets bought before 2026 or transferred from wallets or DeFi platforms – may still lack basis information. A missing or zero basis is a risk signal, not automatic proof that the form is wrong. Use this page to identify potential gaps, gather your transaction history and choose the next step.Educational screening only. This site is not tax, legal, accounting or financial advice. Confirm your records with official exchange exports, wallet history and a qualified tax professional before filing.
Already know which exchange or wallet caused the issue? Start with the matching help page below.
What is a 1099‑DA mismatch?
Form 1099‑DA is used by brokers and custodians to report proceeds from digital‑asset sales and exchanges starting with transactions on or after Jan 1 2025. In its early years it may not include cost basis, and it only covers transactions conducted through brokers that take possession of the digital assets. A 1099‑DA mismatch happens when the amounts on the form do not match your exchange records, wallet history, crypto tax software, or original purchase records. The mismatch may involve proceeds that look too high, missing or zero cost basis, wallet‑to‑exchange transfer gaps, exchange‑to‑exchange transfer gaps, or crypto tax software differences. The first step is not to assume the form is wrong; it is to identify whether the mismatch involves proceeds, cost basis, transfers or software imports.
* Proceeds that look too high
* Missing or zero cost basis
* Wallet‑to‑exchange transfer gaps
* Exchange‑to‑exchange transfer gaps
* Crypto tax software differences
Why your crypto 1099‑DA may not match your records
A mismatch occurs when the reporting platform lacks the full history behind the asset that was sold or exchanged.
Common causes include:
* The sale platform did not see the original purchase. You may have bought the crypto somewhere else and later transferred it to the platform that reported the sale. The platform may know the proceeds but not what you originally paid.
* A wallet transfer broke the visible basis trail. Moving crypto through MetaMask, Trust Wallet, Phantom or Ledger can make it harder to connect the final sale to the original purchase. The transfer itself is not taxable, but the missing purchase history behind the transfer needs review.
* Multiple exchanges each hold only part of the history. One exchange may have the purchase record; another exchange may have the sale record. Without connecting the two, the form will only show partial information.
* Crypto tax software may be missing imports. Crypto tax software can show different results when wallets, exchanges, fees, swaps or older transactions are missing or classified differently.
* Early years of Form 1099‑DA focus on proceeds. Brokers must report gross proceeds starting Jan 1 2025, but basis reporting applies only to covered digital assets sold on or after Jan 1 2026. Non‑custodial platforms are not currently required to issue Form 1099‑DA.
What kind of 1099-DA problem are you dealing with?
Choose the issue that sounds closest to your situation:1. Missing cost basis
Your form shows a sale but the original purchase price is missing, incomplete or not connected to the transaction.2. Zero cost basis
Your 1099‑DA or crypto tax software treats the asset as if it had no purchase cost. This is a warning signal to review your records, not automatic proof that the form is wrong.3. Wallet‑to‑exchange transfer gap
You moved crypto from a self‑custody wallet (MetaMask, Trust Wallet, Phantom, Ledger, etc.) to an exchange before selling. The exchange may show the sale but not the earlier purchase history.4. Exchange‑to‑exchange mismatch
You bought on one platform and sold on another. The selling platform may report proceeds without seeing the original purchase record.5. Crypto tax software mismatch
Your 1099‑DA, exchange export and crypto tax software show different proceeds, basis or gain numbers. This usually means one source has missing data, different transaction classifications or different assumptions.6. Multi‑wallet or DeFi history
Your records include swaps, bridges, liquidity pools, staking or multiple wallets. These histories often need more careful reconciliation before the numbers can be trusted.
Use the calculator below first. Then go to the exchange or wallet help page that best matches your issue.
Crypto 1099-DA Mismatch Risk Calculator
Estimated 1099-DA Mismatch RiskScore: 0 / 100
Risk Level: Not Calculated
Estimated Missing Cost Basis Exposure$0
What your 1099‑DA mismatch result means
- Low review signal
Your records may contain enough visible proceeds and basis information for an initial review. Still compare the form against your exchange exports, wallet history and crypto tax software reports before relying on the numbers.- Medium review signal
Some transfer history, purchase records or cost basis details may be incomplete. Gather your records and review the mismatch before filing or sending numbers to a preparer.- High review signal
Your reported gain may rely on incomplete cost basis or transfer history. This does not automatically mean the form is wrong, but it does mean your records should be reviewed carefully before filing.Estimated missing cost basis exposure
This estimate is educational only. Final numbers depend on your full transaction history, original purchase records, wallet activity, exchange exports, fees, transfer matches and reconciliation method.
Records to gather before trusting or disputing a 1099‑DA
Before assuming a 1099-DA is wrong, gather the records that show the full transaction trail.Exchange records
Download trade history, deposits, withdrawals, tax reports and CSV exports from each exchange you used. For the 2025 tax year, brokers are required to issue Forms 1099-DA for reportable sales and exchanges. These forms will show gross proceeds but may not include basis until 2026.Wallet records
Save wallet addresses, transaction hashes, transfer dates, swap records, bridge activity and wallet export history. If your crypto moves through self-custody, these records are crucial for reconstructing cost basis.Original purchase records
Find where the asset was first acquired – including date, amount, purchase price, fees and platform. If the asset was bought before 2026, it may be treated as a non-covered digital asset and basis reporting may remain optional.Transfer trail
Match outgoing transfers from one platform to incoming transfers on another so the same asset is not treated as an unsupported or new asset.Crypto tax software reports
Save import summaries, missing basis warnings, transaction classifications and gain/loss reports from Koinly, CoinLedger or other software.Professional review notes
If the numbers still do not match, bring your organized records to a qualified tax professional before filing.
Get your 1099-DA cleanup path
Choose the next step that fits your records
Free 1099-DA records checklistUse the free checklist if you want a simple way to organize your records before reviewing a mismatch. The checklist helps you collect exchange CSVs, wallet addresses, transfer records, original purchase history, missing basis warnings, crypto tax software reports, support notes, and questions for a tax professional.This is the best next step if you are still gathering records or are not sure whether the issue is caused by proceeds, cost basis, transfers, or software imports.
1099-DA Mismatch Rescue GuideUse the 1099-DA Mismatch Rescue Guide if you want a plain-English walkthrough for organizing a possible crypto tax form mismatch. The guide covers missing cost basis, zero cost basis, wallet-to-exchange transfers, exchange-to-exchange transfers, Coinbase mismatch issues, Robinhood mismatch issues, Kraken mismatch issues, Binance mismatch issues, MetaMask or self-custody wallet history and crypto tax software reports that do not match the form.The guide does not provide tax, legal, accounting or financial advice. It helps you organize records and understand common mismatch causes. Early years of Form 1099-DA reporting focus on gross proceeds; using the guide to reconstruct basis can help you identify where gaps may exist before basis reporting becomes mandatory in 2026.
Use Koinly when your records include MetaMask, DeFi, smart contracts, Trust Wallet, Phantom, Ledger, swaps, bridges, several wallets or exchanges, or older transaction history. Koinly is best for MetaMask, DeFi and complex wallet histories.
Software does not replace review
Software does not replace review. It helps rebuild transaction history faster and reduces the chance of missing basis records. That is when cost basis gaps are easiest to catch and fix.
Software does not replace review. It helps rebuild transaction history faster and reduces the chance of missing basis records.
That is when cost basis gaps are easiest to catch and fix.
Check your 1099-DA issue by platform
Different platforms create different mismatch patterns. Choose the page that matches where the sale, transfer, or missing basis issue appears. Each link explains the common mismatch issue and the best next step.
Kraken 1099-DA
Kraken cost basis may be incomplete when assets came from another wallet or exchange. Review deposits, withdrawals and purchase history.
Robinhood Crypto 1099-DA
Robinhood form numbers may not match software, transfer or prior purchase records. Compare Robinhood exports with your full history.
MetaMask wallet transfer mismatch
MetaMask wallet activity, swaps, bridges, or transfers may not connect to the final sale. Rebuild the wallet transaction trail.
Coinbase / Binance / Multi-Exchange Issues
Using more than one exchange can make a 1099‑DA look incomplete or too high. The selling platform may see the sale but not the original purchase record from the other exchange. Compare sale proceeds, deposit/withdrawal history, and original acquisition history across all platforms.
Need to explain a 1099‑DA mismatch clearly?
A 1099‑DA mismatch letter can help you document what does not match between your tax form, exchange records, wallet history, and crypto tax software reports. This template does not prove the form is wrong or guarantee an exchange will correct a form. It is not tax or legal advice. Use it to organize the issue before contacting exchange support, sharing records with a preparer, or requesting professional review.
For recordkeeping, tax preparer review, or exchange support — not legal or tax advice.
Frequently Asked Questions About 1099-DA Mismatch
6. Should I dispute a 1099-DA with missing cost basis?
Only after identifying a specific mismatch and gathering supporting records. Missing basis may mean the platform lacked acquisition history; it does not automatically prove the form is wrong. A dispute letter can help organize the issue for exchange support or professional review.7. What should I do first if I am not sure where the mismatch started?
Start by identifying whether the issue involves proceeds, cost basis, transfers, or software imports. Then run the checker, gather records, use the cleanup assistant, and decide whether a checklist, guide, software, or professional review is needed.
Important Educational Disclaimer
1099dacheck.com provides educational screening tools and record‑organization resources only. It does not provide tax, legal, accounting, or financial advice. A missing or zero cost basis entry is a warning sign that records may need review. It is not automatic proof that a 1099‑DA is wrong. Always verify your exchange exports, wallet history, transfer records, cost basis records, and crypto tax software results before filing. Consult a qualified tax professional about your specific situation.