IRS Crypto Record Keeping Guide

The IRS doesn't care how you feel about your crypto. They care about what you can prove.

I'm Chris Herbst, founder of CountDeFi. We've been doing forensic crypto tax work since 2017, and the single most common problem we see isn't bad math or wrong forms. It's missing data and documentation.

A client comes in with a six-figure portfolio, years of trading history, and almost nothing in writing. That's not a tax problem. That's a data problem. And in 2026, with Form 1099-DA now reporting your proceeds to the IRS, it's a problem with consequences.

Record keeping for IRS crypto tax is a big deal and one with very clear requirements. This 2026 guide walks through exactly what the IRS requires you to document, what happens when you can't, and how we've helped clients fill the gaps.

What Crypto Tax Records Does the IRS Actually Require?

• The IRS treats crypto as property. Every disposal needs documented cost basis, dates, and fair market values.
• You must maintain records sufficient to establish the positions taken on your tax returns (IRC §6001).
• 1099-DA now creates a data trail the IRS can match against your return. Your documentation is what makes or breaks that match.

The Legal Standard

The Internal Revenue Code requires taxpayers to maintain records sufficient to establish the positions taken on tax returns. For crypto, this means keeping documentation of receipts, sales, exchanges, or other dispositions of digital assets and the fair market value at the time of each transaction. This comes directly from IRS FAQ A-46 on virtual currency transactions and applies to every taxable event.

In practice, that means the IRS expects you to be able to produce, for every disposal, the following data points.

The Seven Data Points the IRS Expects

For every crypto disposal reported on Form 8949, you need documentation supporting:

1. Description of the asset (e.g., 0.5 BTC, 2.3 ETH)
2. Date acquired
3. Date sold or disposed of
4. Proceeds (fair market value received, in USD)
5. Cost basis (what you originally paid, in USD, including fees)
6. Gain or loss
7. Holding period (short-term vs. long-term)

That's seven data points per line item. If you made 500 trades last year, that's 3,500 documented facts. If you made 5,000 trades, that's 35,000.

I had a client in 2024, a software engineer in Denver, who had 3,200 transactions across Coinbase, Kraken, and three DeFi protocols. He'd kept nothing. No CSVs, no screenshots, no notes. His CPA told him to "just use TurboTax." We spent six weeks reconstructing his entire transaction history from blockchain data and exchange API pulls. Every single data point, documented and sourced. His Form 8949 ran to 94 pages.

What Counts as Acceptable Documentation

The IRS doesn't prescribe a specific format. What matters is that you can substantiate your positions. Acceptable documentation generally includes:

• Exchange-generated transaction histories (CSV exports, API data)
• Blockchain explorer records (Etherscan, Solscan, BscScan timestamps and transaction hashes)
• Bank and credit card statements showing fiat on-ramps
• Email confirmations of purchases, withdrawals, or deposits
• Screenshots of account balances at relevant dates
• Records from crypto tax software showing methodology and calculations

What doesn't count: memory, rough estimates without sourcing, or "I think it was around $30,000."

How 1099-DA Changes Your Documentation Burden in 2026

• Brokers now report your gross proceeds directly to the IRS.
• For 2025 transactions, cost basis is generally not reported, which means the burden of proving your basis falls entirely on you.
• Without documentation, the IRS may treat your basis as $0, making your entire proceeds look like taxable gain.
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I cover the full story on Form 1099-DA and how it will impact US crypto investors in my February 2026 Guide. It's important that you understand the impact this is going to have on avoiding IRS audits.

The Matching Problem

Starting with tax year 2025, brokers like Coinbase, Kraken, and Gemini are issuing Form 1099-DA. The IRS receives a copy. Their Automated Underreporter system compares what's on your return against what brokers reported.

Here's what's new: the IRS now has one side of the equation (your proceeds) whether you report them or not. What they don't have is your cost basis. For 2025 transactions, brokers report proceeds but are generally not required to report basis. That means the documentation burden for basis falls entirely on you the investor.

What Happens Without Basis Documentation

I had a client who sold $85,000 worth of Ethereum in 2024. He'd originally purchased it for $72,000 on an exchange that later shut down. His actual gain was $13,000. But he couldn't produce acquisition records, so his return showed proceeds with no substantiated basis. The IRS proposed adjustments based on the full $85,000 as gain.

We reconstructed his basis using bank statements showing the original wire transfers, blockchain explorer timestamps matching the deposit to his wallet, and archived email confirmations from the defunct exchange. His liability dropped from what would have been tax on $85,000 to tax on $13,000.

Crypto Tax Documentation Requirements by Transaction Type

• Different transaction types require different documentation.
• DeFi, staking, and NFT activity each have specific data requirements that go beyond simple buy/sell records.
• The IRS is still developing guidance on some complex transaction types, but the record-keeping obligation applies regardless.

Exchange Trades (Bitcoin, Ethereum, Altcoins)

The simplest category. For every trade on Coinbase, Kraken, Gemini, or any centralized exchange, you need the acquisition date and price, the disposal date and proceeds, and the resulting gain or loss. Most exchanges provide this in CSV or API format. Download it, as we've seen exchanges can crash out, so don't assume your records and statements will be there forever.

We had a client who'd traded heavily on a platform that later restricted US accounts. By the time she needed her records for a 2023 amended return, the export function was gone. We rebuilt her history from blockchain data, but it took three weeks of forensic work that wouldn't have been necessary if she'd downloaded her CSVs when they were available.

DeFi Transactions (Uniswap, Aave, Curve)

DeFi is where tax documentation gets complicated. Token swaps are generally taxable disposals. Liquidity pool deposits, wrapping, and bridging can be fact-dependent and may create taxable income or gains depending on how the transaction is structured. The IRS is still developing specific guidance on many DeFi activities (Notice 2024-57 carved out several transaction types for further study), but the record-keeping obligation applies regardless.

For every DeFi interaction, document the wallet address, the transaction hash, the tokens involved (in and out), the USD fair market value at the time, and the protocol used. This level of detail is what separates a defensible return from an indefensible one. My DeFi tax guide is a good read for more info on DeFi record-keeping for the IRS.

Staking and Mining Income

Staking rewards and mining income are generally taxable as ordinary income at fair market value when you gain dominion and control over the tokens. You need to document the date received, the number of tokens, and the USD fair market value at that moment, not when you eventually sell.

When you later sell those tokens, the sale goes on Form 8949. Your cost basis is the fair market value at the time of receipt. If you don't document that original value, you risk paying tax twice: once as income, and again on the full sale amount as capital gains with no basis offset.

One of our clients had been staking Solana for two years and had never recorded the value of rewards at receipt. We pulled the staking history from on-chain data and matched each reward to historical pricing. The difference between documented basis and zero basis was over $14,000 in unnecessary tax.

NFT Purchases and Sales

NFT transactions follow the same property rules. Buying an NFT with Ethereum is a disposal of Ethereum (taxable) and an acquisition of the NFT. Selling the NFT later is another taxable event. For IRS record-keeping, document the ETH price at time of purchase, the purchase price of the NFT, and the sale price when you dispose of it. More on this in my NFT tax guide.

Wallet-to-Wallet Transfers

Transfers between your own wallets are not taxable, but they must be documented for the IRS. If you move Bitcoin from Coinbase to a Ledger and later sell from that Ledger, the cost basis needs to follow the asset. Without transfer documentation, the cost basis chain breaks, and the sale can look like 100% profit.

Under 1099-DA, the receiving platform may report your sale proceeds with no basis attached. If you can't prove the transfer, the IRS sees gain where there is none.

How Long to Keep IRS Crypto Tax Records

• The IRS can generally audit returns filed within the last three years.
• If income is understated by more than 25%, the window extends to six years.
• For fraud or failure to file, there is no statute of limitations.
• Practical recommendation: keep crypto records indefinitely.

Why Indefinite Record Retention Matters for Crypto

Unlike traditional securities with a clear brokerage paper trail, crypto records can be uniquely fragile. Exchanges shut down. Platforms purge old data. APIs get deprecated. If you need to substantiate a cost basis from 2017 for a sale in 2025, you need those 2017 records.

I tell every client the same thing: download your data now, store it in multiple locations, and never delete it. The cost of storage is zero. The cost of not having records when the IRS asks is not.

Common IRS Record-Keeping Failures We See

• Relying on exchange data that's no longer accessible.
• Assuming transfers between wallets don't need documentation.
• Failing to record fair market values of staking rewards at receipt.
• Using a single cost basis method inconsistently across assets.

These aren't edge cases. These are the situations that walk through our door every week. And every one of them becomes significantly harder to resolve the longer it goes undocumented.

About Cost Basis

‍For most US taxpayers, the IRS framework for basis is: use Specific Identification if you can adequately identify which units were disposed of; otherwise, FIFO generally applies as the default. Some taxpayers use strategies like HIFO as a form of specific identification. Whatever method you choose, document it, apply it consistently, and keep records showing which specific units were sold in each transaction. Because cost basis is such a big deal in crypto tax strategy I keep an updated guide on the various cost basis methods US investors can use.

Why Your Records Now Matter Under Oath

In March 2026, a new IRS examination document emerged that changes how I think about record-keeping conversations with clients. Based on a version that has circulated among tax professionals, the IRS appears to be issuing an IDR-style attachment during active crypto audits. Referred to as the Historical Digital Asset Form, or HDAF, it requires taxpayers to disclose, under penalties of perjury, every exchange account, self-custody wallet, and DeFi product they have ever used, going back to their very first digital asset activity.

The perjury certification is what makes this different from a standard information request. An inadvertent omission like a forgotten exchange from 2018 or a wallet address you can't account for, doesn't just create a recordkeeping gap. It creates an inconsistency in a signed sworn statement, which the IRS can use when assessing whether an omission was accidental or deliberate. That is a different category of problem.

The practical implication is straightforward: the records you maintain today are not just for filing an accurate return. If you ever find yourself in a crypto audit, they are what you will need to sign off on.

We've covered the HDAF in full detail, including what it asks for, what the perjury certification means in practice, and what to do if you receive one: read our guide to the IRS Historical Digital Asset Form.

How CountDeFi Handles Crypto Tax Documentation

When a client comes to us with incomplete records, we don't guess. We reconstruct.

Our Precision 7™ System is built for exactly this: pulling exchange data, tracing on-chain activity across wallets and protocols, reconciling 1099-DAs against actual transaction history, and producing documentation that meets IRS standards. We've done this for clients with records going back to 2013, across defunct exchanges, dozens of wallets, and thousands of DeFi interactions. I cover what this looks like in my guide,

If your records are incomplete, start with a free call. This is what we do.

FAQs: IRS Crypto Tax Documentation

What records does the IRS require for cryptocurrency?
‍The IRS requires records sufficient to establish the positions on your return. For crypto, that means documentation of every acquisition and disposal: dates, amounts, fair market values in USD, cost basis, and the resulting gain or loss.

How long should I keep crypto tax records?
‍At minimum three years from filing, six years if income may be understated by more than 25%. In practice, keep crypto records indefinitely. Exchange data disappears, and you may need to prove basis from years earlier.

What if I don't have complete records?
‍You may need to reconstruct your transaction history from the best available evidence: blockchain explorers, bank statements, email confirmations, and exchange fragments. CountDeFi specializes in this kind of forensic data reconstruction.

Does the IRS know about my crypto transactions?
‍With 1099-DA, brokers report your proceeds directly to the IRS. The IRS also obtains data through John Doe summonses and blockchain analytics tools. For more on this, see our guide on whether the IRS can track cryptocurrency.

What happens if my 1099-DA doesn't match my return?
‍Mismatches can trigger a CP2000 notice. The IRS compares broker-reported proceeds against your Form 8949. If the numbers don't match, they'll propose adjustments. Your documentation is what proves your actual gain or loss.