How do I claim the lifetime capital gains exemption on my tax return?

The lifetime capital gains exemption is not applied for in advance and it does not arrive on its own. After a sale of qualifying shares, the owner claims it on the tax return for the year of the sale, through a sequence of forms. CRA’s own guidance names the pieces: Schedule 3 reports the gain, Form T657 calculates the capital gains deduction, and line 25400 of the return is where the deduction is claimed. Getting the order right matters, because each step feeds the next. This guide walks through that order for a seller who has already sold, and flags where the tax adviser’s judgment is needed.

Report the sale on Schedule 3 first

CRA says to use Schedule 3, Capital Gains or Losses, to calculate and report your taxable capital gains or net capital loss. The gain itself is worked out the usual way. CRA’s page on calculating capital gains says to subtract the property’s adjusted cost base, plus the outlays and expenses incurred to sell it, from the proceeds of disposition. CRA’s Chapter 2 guide gives qualified small business corporation shares and qualified farm or fishing property their own headings in the Schedule 3 instructions, so read those headings before choosing the line for your sale.

Confirm the shares qualify before you claim

Eligibility starts with the property sold. CRA’s guide says a share is a qualified small business corporation share only if all the listed conditions are met. At the time of sale it must be a share of a small business corporation owned by you, your spouse or common-law partner, or a partnership of which you were a member. Throughout the part of the 24 months before the sale while it was owned by you, a partnership you belonged to or a person related to you, it must have been a share of a Canadian-controlled private corporation meeting an asset test CRA sets out in full. Throughout those 24 months, no one other than you, such a partnership or a related person may have owned it, and CRA describes a special rule, with its own exceptions, for shares the corporation issued. Our answer on whether your shares qualify goes through those tests.

Calculate on Form T657, then claim line 25400

CRA’s line 25400 page says to complete Form T657, Calculation of Capital Gains Deduction, and then, after completing it, claim the amount, up to the maximum allowable amount, of the total capital gains deduction on line 25400. CRA says the claim reduces your taxable income. The same page says the deduction covers dispositions of qualified small business corporation shares, and it has a section on the lifetime limit. Because the claim is capped by a limit that carries across your lifetime, ask your accountant for the record of earlier claims before filling in the form.

Other forms that can come with it

CRA’s line 25400 page says that if you have investment income or investment expenses in any years from 1988 to 2025, you must also complete Form T936, Calculation of Cumulative Net Investment Loss. A seller with a history of investment expenses should therefore expect that form. CRA’s Chapter 2 guide also points to Form T691, Alternative Minimum Tax, to calculate federal tax payable under that regime, and notes that the calculation of adjusted taxable income for it has changed under proposed changes. Whether the exemption removes alternative minimum tax on a sale is a separate question, covered in our answer on that point.

If the price is paid over several years

CRA’s page on capital gains reserves says a reserve usually lets you report a portion of the gain in the year you receive the proceeds, based on the portion not yet received. The line 25400 page adds that when a reserve from an earlier sale of qualified small business corporation shares comes into income, the deduction you can claim is based on the year the property was disposed of. A seller taking a vendor take-back should therefore keep the year-of-sale records, not only the year-of-payment ones.

Keep the claim in the right order

CRA’s Chapter 2 guide says that, under proposed changes, a deduction for qualifying business transfers on line 25395 is claimed before a deduction on line 25400 for the same disposition. If your sale also involves one of those newer claims, the order on the return matters, so raise it with your adviser early.

• Collect the share purchase records and sale documents that show the adjusted cost base, proceeds and selling costs.
• Test the shares against each CRA condition, including the 24-month period, before the figures go on a form.
• Complete Schedule 3, then Form T657, then enter the result on line 25400.
• Ask whether Form T936 or Form T691 applies to your return.
• Have an accountant check the claim against your earlier use of the limit before filing.