“Today’s announcement of co‑ordinated international action on cryptoassets is a major step forward, marking another important milestone towards the widespread and co-ordinated approach to combat tax evasion through greater transparency and exchange of information,” Secretary-General Cormann said.

“We strongly welcome the extensive support being shown for quick action to make the international exchange of information collected under the OECD standard on cryptoasset reporting a reality. The international community can count on the OECD and the Global Forum on Transparency and Exchange of Information for Tax Purposes to ensure that the tax transparency architecture remains both up-to-date and effective going forward.”

The Crypto-Asset Reporting Framework (CARF) is a key component of the International Standards for Automatic Exchange of Information in Tax Matters developed by the OECD under a G20 mandate. It provides for the automatic exchange of tax-relevant information on cryptoassets and comes against the backdrop of a rapid adoption of the use of cryptoassets for a wide range of investment and financial uses.

The press release said records should be kept "when you purchase, dispose, or mine cryptocurrency to ensure you have accurate information of your activities. This information is important for your own records and for filing your tax returns."

When an investor trades, sells or mines cryptocurrency, they have to report any income or capital gains from those activities on their tax return. However, they may also be able to report their expenses and losses. If they exchange taxable goods or services for cryptocurrency, they may have to report goods and services tax / harmonized sales tax (GST/HST).

All records should be kept about cryptocurrency transactions, including: 

• date of the transaction;
• the cryptocurrency addresses;
• the transaction ID;
• receipts for the purchase or transfer of cryptocurrency;
• value of the cryptocurrency in Canadian dollars when you made the transaction;
• a description of the transaction and the other party (such as their cryptocurrency address);
• exchange records;
• wallet records;
• accounting and legal costs; and
• software costs related to managing your tax affairs.

Miners of cryptocurrency should also keep the following records:

• receipts for purchasing cryptocurrency mining hardware;
• receipts to support your expenses associated with the mining operation;
• the mining pool contracts and records;
• any other records on the mining activities; and
• the disposal of cryptocurrency earned through the mining activities.

More details can be found on the Agency's keeping records page.

The CRA said:

"If you are mining as a business, you have to pay tax on your business income from the mining of the cryptocurrency and any capital gains on the sale of the cryptocurrency that you validated.

"If you did not report your income or capital gains from transactions in cryptocurrency, you may have to pay tax, penalties and interest on that income or capital gain. You can avoid or reduce penalties and interest by voluntarily correcting your tax affairs. To correct your tax affairs (including corrections to GST/HST returns) and to report income that you did not report in previous years, you may:

• Ask for a change to your income tax and benefit return
• Adjust a GST/HST return
• Apply for a correction through the Voluntary Disclosures Program."