Adjusted cost base for a Questrade account

A self-directed account that has been open for years accumulates the three things that make an adjusted cost base hard: holdings bought in US dollars, distributions that were reinvested automatically, and a series of partial sales that each had to be measured against an average.

None of that is unusual, and none of it is a problem with any broker. It is what the rule asks for. This page is about rebuilding the number when those three are in play. For the calculation itself, read adjusted cost base explained first.

US-dollar holdings: the rate is per transaction, not per year

Your adjusted cost base is a Canadian-dollar figure, and every component of it is converted at the rate in effect on the day of that transaction.

That means a US-listed holding bought across several years has a cost base assembled from several different exchange rates, one per purchase. Converting the whole position once, at today's rate or at a year-end rate, produces a different and incorrect number. The same applies on the way out: proceeds convert at the rate on the sale date.

The consequence people find surprising is that currency movement alone creates a capital gain or loss in Canadian dollars, even when the US-dollar price has not moved at all. That gain is real and reportable.

DRIP: every reinvestment is a purchase

If distributions are reinvested, each reinvestment buys shares, and each of those purchases raises your adjusted cost base and changes the average. No cash arrives in the account, so it is easy to treat the whole thing as one holding bought once. It is not; it is one holding bought many times.

Over several years a DRIP position can have dozens of separate acquisitions behind it, each at its own price, each at its own exchange rate if the fund is US-listed. Skipping them understates the cost base, which overstates the gain and means paying tax that was never owed.

Partial sales measure against the average, not against a lot

Canada does not let you pick which shares you sold. A partial sale is measured against the average cost of the whole pooled position, and after the sale the average per share is unchanged while the total cost falls proportionally.

This matters in a long-running account because the errors compound: an average that was wrong three sales ago has been wrong in every calculation since. The adjusted cost base calculator runs a single security through buys, sells and commissions and shows what the base became after each transaction, which is the quickest way to check a position you are unsure about.

Then pool it across your other accounts

Identical property pools per taxpayer, not per account. If the same security is also held at another institution, the two positions share one adjusted cost base, and neither broker can see both sides.

Adjusted cost base across two brokerages works through what that does to a sale. It is the step most often skipped, and it is the one no brokerage statement can do for you.

Reading the slip against your own number

A T5008 reports proceeds per account, and box 20 is where a cost amount would sit. Treat your own records as the authority: the slip is produced by an institution that cannot see your other accounts, and CRA expects the figure you file to be your ACB.

T5008 box 20 and your ACB explains how to read the two together, and the T5008 and cost base checker shows the Schedule 3 totals each version implies.

Getting the history into one place

Questrade is a supported read-only connection in Luum, so the account can be linked and its transaction history used to build the cost base rather than retyped. The connection can see positions and transactions and cannot place a trade or move cash.

If you prefer not to connect it, every plan takes a holdings upload, and transaction history import is available on the paid plans. For cost base the distinction matters: a holdings snapshot shows what you own now, and an average cost needs every purchase that built it.

Common questions

What exchange rate do I use for a US holding?

The rate in effect on the date of each transaction, applied to that transaction. Not one rate for the position and not a year-end rate. The Bank of Canada publishes the daily rates, and its page is the authority rather than any figure republished elsewhere.