Recording your adjusted cost base for crypto

The adjusted cost base, often shortened to ACB, is the figure that a gain or loss is measured against when you dispose of a crypto asset. According to the Canada Revenue Agency, it is generally the cost of the asset plus the expenses of acquiring it. The term sounds technical, but the idea is plain. It is your starting point for the tax calculation, the record of what the asset cost you in Canadian dollars at the time you got it. Without that record, a later sale, swap or payment leaves you guessing about how much of the proceeds is a gain. Most people discover this problem only when a return is due and the old purchases are scattered across apps, emails and bank statements.

The calculation itself follows a fixed order. First, the Canada Revenue Agency describes a capital gain as the proceeds of disposition minus the adjusted cost base and the outlays and expenses of the sale. Second, a loss is the same sum when the result comes out negative. Third, a 2024 tax tip from the agency describes the adjusted cost base as usually the weighted average cost of the crypto asset, which means purchases of the same asset are blended together rather than tracked one by one. Finally, according to the same tip, gains and losses are reported in the crypto-assets section of Schedule 3 of the T1 return. Each step depends on the one before it, so one missing purchase record weakens every figure after it.

Imagine a man named Tomas who acquires a small amount of one asset in the spring and a further amount in the autumn. At each purchase he saves a screenshot of the confirmation and adds a line to a spreadsheet with the date, the asset, the quantity, the cost in Canadian dollars and any expenses of acquiring it. Months later he swaps part of the holding for another asset. He opens the sheet, blends the two purchases into an average cost for the first asset, and notes the value of the swap on the day it happened. When the return is prepared, the sheet answers each question without a search through old emails.

Mistakes in cost records usually come from habits rather than from the rules. People record the quantity but not the Canadian-dollar cost. They leave out the expenses of acquiring the asset, so the base looks smaller than it is. They mix several wallets or apps into one list and cannot tell which purchase belongs where. Some forget that a swap of one asset for another is a disposition, so the incoming asset needs a new cost entry too. Others rely on an exchange's export alone and lose access when the account closes. The agency's books-and-records page for crypto does not set out a separate cost-base method, which is why every purchase record and its expenses should be kept.

A short set of questions can be answered at your desk with your own papers. Does each purchase have a date, an asset name, a quantity and a Canadian-dollar cost? Are the expenses of acquiring the asset written beside it? Do you keep the confirmation, the statement or the export that backs each line? Can you show how the weighted average was reached for each asset? Is every swap, sale and payment recorded as a disposition with its proceeds and its own expenses? Does each wallet and account that you use appear in the list? If you cannot tell which entry belongs to which account, rebuild the list from statements before the filing season begins.

This page explains a way to organize records and does not decide how any transaction is taxed. Your facts, your province and your other income all matter, and the Canada Revenue Agency's guidance can change, so read its crypto pages and the capital gains instructions yourself, and check the date on each page. A qualified tax professional can review your particular case, and the agency itself answers questions about its own rules. Nothing here is tax, legal or financial advice. Keep your own copies of anything you rely on. The sources below are the agency pages that describe the adjusted cost base, the gain formula and the reporting of crypto gains and losses on the return.

• Record the date, asset, quantity, Canadian-dollar cost and acquisition expenses for every purchase
• A gain is proceeds minus the adjusted cost base and the outlays of the sale, according to the Canada Revenue Agency
• Keep each confirmation or statement that backs a line, since the agency sets no separate cost-base method for crypto