Proper record keeping is the foundation of crypto tax compliance. Tax authorities worldwide are increasingly sophisticated at using blockchain analytics to detect unreported gains — but they also require taxpayers to demonstrate their cost basis and transaction history. Without good records, you may end up paying tax on your gross proceeds rather than your actual gains.
What Records You Must Keep
Transaction Dates
Exact date and time of every purchase, sale, trade, or transfer. Time matters for calculating holding periods and determining applicable tax rates.
Transaction Amounts
The exact quantity of cryptocurrency involved in each transaction (in crypto units and in your local fiat currency value at the time).
Fiat Value at Transaction Time
The market price of the crypto in your local currency at the exact moment of each transaction. This establishes your cost basis and disposal value.
Wallet Addresses
The sending and receiving wallet addresses for each transaction. Proves ownership and establishes the chain of custody.
Exchange Records
Full transaction history from every exchange you've used. Download CSV exports regularly — exchanges do close down and historical data can be lost.
Income Records
For staking rewards, mining income, DeFi yields: the date received, the amount, and the fiat value at the time of receipt.
How to Retrieve Historical Transaction Data
Centralised Exchanges (Binance, Coinbase)
Log in → Account → Transaction History → Export CSV. Most exchanges allow up to 3 years of history export. Download regularly as some restrict historical access after account closure.
Crypto Tax Software (Koinly, CoinTracker)
Connect via API keys or import CSV exports. The software automatically categorises transactions, applies cost basis methods, and generates compliant tax reports for your jurisdiction.
Blockchain Explorers
For any wallet address, blockchain explorers (Etherscan for Ethereum, blockchain.com for Bitcoin) provide complete transaction history. Useful for self-custody wallets not connected to exchanges.
DeFi Transaction Records
DeFi activity can be complex to track. Tools like Koinly and TokenTax specialise in DeFi parsing. Alternatively, Zerion and DeBank provide DeFi portfolio history views.
Record Retention Requirements by Jurisdiction
| Jurisdiction | Authority | Required Retention Period |
|---|---|---|
| United Kingdom | HMRC | 5 years after the 31 January filing deadline |
| United States | IRS | 3 years (7 if substantial underpayment suspected) |
| Australia | ATO | 5 years from the date of the CGT event |
| European Union | Varies by member state | 6–10 years depending on country |
| Canada | CRA | 6 years from the end of the relevant tax year |
💡 Best Practice
Keep records for the full holding period of each asset PLUS the maximum retention period for your jurisdiction. If you bought Bitcoin in 2020 and are still holding it, keep all records from 2020 onwards — you'll need them for when you eventually dispose of it.
Frequently Asked Questions
What records do I need to keep for crypto taxes?
Transaction dates, amounts, fiat values at time of transaction, wallet addresses, exchange CSV exports, and income records (staking/mining). Keep these for the full holding period plus your jurisdiction's retention requirement (typically 5-7 years).
How do I track crypto transactions for taxes?
Use dedicated crypto tax software (Koinly, CoinTracker, TaxBit) that auto-imports from exchanges and wallets. Download CSV exports from all exchanges regularly. Use blockchain explorers for self-custody wallet history.
Disclaimer: Educational content only. Tax rules vary by jurisdiction. Consult a qualified tax professional. Wealtii is early-stage and NOT YET REGULATED in all jurisdictions.