Understanding 1099-DA for Bitcoin
What 1099-DA Actually Captures in 2026
Starting with trades after December 31, 2025, brokers must issue Form 1099-DA for every Bitcoin disposition above $600 in aggregate proceeds. The form reports gross proceeds, acquisition date if known, and the broker’s default FIFO cost basis. Notice 2014-21 still governs the underlying tax treatment, so every sale or exchange remains a taxable event. If you sold 0.12 BTC for $8,400 on March 15, 2026, the exchange will list that $8,400 even if your true basis was $11,200 from a 2024 purchase. Pub 550 requires you to report the correct gain or loss on Form 8949, not the broker’s default number. The gap between reported proceeds and your real basis creates immediate underpayment risk if you ignore it.
How Exchanges Will Default Your Basis
Most platforms will use FIFO and whatever wallet address they control. That produces the wrong number whenever you moved coins to self-custody or bought on another venue. Rev. Proc. 2019-09 allows specific identification, including HIFO, provided you keep timestamped records of each lot’s acquisition date, cost, and transaction ID. If you bought 0.05 BTC at $29,000 in January 2023 and 0.07 BTC at $42,000 in June 2024, selling 0.06 BTC in 2026 under HIFO lets you use the $29,000 lot first. Without those records the exchange’s FIFO figure stands, and you pay tax on an extra $780 of gain at 2026 rates. Keep the wallet export plus exchange CSV; that packet satisfies the “adequate identification” test.
Self-Custody Bitcoin Falls Outside Broker Reporting
Form 1099-DA only covers dispositions that touch a reporting broker. Move coins to your own hardware wallet and later sell peer-to-peer or on a non-custodial DEX and no 1099-DA arrives. The IRS still expects you to report the gain under Notice 2014-21. If you later deposit those same coins to an exchange that issues 1099-DA, only the final sale appears on the form. Your earlier self-custody transfer carries a zero proceeds line on the 1099-DA, but you must still track the original basis from 2023 or 2024. The mismatch forces manual reconciliation every year you touch a reporting platform.
Reconciling the 1099-DA Numbers Yourself
Download the 1099-DA CSV in January 2027 and compare every line against your own lot-level ledger. Flag any sale where your HIFO basis differs from the broker’s FIFO number. Adjust column (e) or (f) on Form 8949 accordingly and attach a statement listing the transaction IDs. If the exchange reports $14,200 proceeds on 0.08 BTC but your records show $9,600 basis, you reduce the gain by $4,600 before the 8949 total flows to Schedule D. IRS auditors accept this method when you produce contemporaneous records; they reject post-hoc spreadsheets. Run the reconciliation before you file, not after the notice arrives.
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Frequently Asked Questions
What is Form 1099-DA?
Form 1099-DA is the new information return brokers must file for digital asset dispositions. It lists gross proceeds, acquisition dates when known, and the broker’s default cost basis. The IRS created it to capture Bitcoin and other crypto sales the same way 1099-B captures stock trades. You still report the correct gain or loss on your return using your own records, not the broker’s default.
When does 1099-DA reporting start?
Reporting begins for dispositions occurring after December 31, 2025. Brokers will send the first 1099-DA forms in early 2027 for 2026 activity. The rule applies to any U.S. person who sells, exchanges, or otherwise disposes of Bitcoin through a reporting broker above the $600 de minimis threshold.
Which exchanges issue 1099-DA?
Any U.S. digital asset broker required to file under the new regulations will issue 1099-DA. This includes Coinbase, Kraken, Gemini, and similar platforms that custody customer Bitcoin. Foreign exchanges without U.S. reporting obligations will not issue the form. If you only use non-custodial tools or overseas DEXs, you will not receive a 1099-DA.
How does it affect self-custody users?
Self-custody Bitcoin sales never generate a 1099-DA because no broker is involved. You must still calculate and report the gain yourself under Notice 2014-21. When you later move coins back to a reporting exchange, only the final sale appears on the 1099-DA. Your earlier self-custody lots require separate tracking so the correct basis flows to Form 8949.
Reconciling 1099-DA with your own records
Compare every 1099-DA line against your lot-level ledger that includes dates, wallet addresses, and transaction IDs. Override the broker’s FIFO basis with your HIFO numbers where records support it. Enter the adjustment on Form 8949 and keep the supporting CSV and wallet exports. This process eliminates the most common mismatch that triggers IRS notices.
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