What you’ll find in these docs
myCostBase is built for ACB tracking Canada workflows in taxable accounts. These docs are for Canadian investors — and the accountants who work with them — who need a defensible adjusted cost base ledger, not just a broker-reported book value. Canadian tax rules require pooling identical securities across every taxable brokerage a tax owner holds, then adjusting that pool for stock splits, ETF return of capital, DRIP reinvestment, and foreign exchange on USD-denominated trades. Broker statements and T5008 slips rarely capture all of that on their own, since a broker only sees the accounts it holds. The guides below walk through each of these mechanics in the order you’ll actually need them: setting up the accounts that belong in your ACB pool, importing history without losing the warnings that matter, handling the calculation edge cases most spreadsheets miss, and reconciling the finished ledger against your T5008 slips before you file.
Start here
If you are new to the product, begin with Getting Started. That page covers the setup decisions that change the legal ACB pool, including which accounts belong in scope and why registered accounts must stay outside it.
Core workflows
The docs are organized around the core myCostBase workflows, in the sequence most investors follow: get the account setup right, import and clean up transaction history, then work through the calculation edge cases — FX conversion, ETF distributions, and options — that spreadsheets and broker book values usually get wrong. The last guide covers reconciling the finished ledger against T5008 slips before you file.
- Getting Started — define the tax owner and mark each account as taxable or excluded before you import anything.
- Importing Transactions — load broker CSVs or manual entries while keeping duplicate detection and transfer-basis warnings intact.
- Pooled ACB Across Brokerages — see why one security held at multiple brokerages still shares a single ACB pool.
- USD and FX Conversion for Capital Gains — convert foreign-currency trades to CAD using transaction-date rates.
- ETF Return of Capital and ACB Adjustments — apply return of capital, DRIP purchases, and reinvested distributions to the running ACB.
- Options Transactions and ACB — track single-leg calls and puts through exercise, assignment, or expiry.
- T5008 Reconciliation and Reports — compare your calculated ACB and proceeds against T5008 figures before filing.
What myCostBase does not do
myCostBase does not replace tax filing software and it does not try to be a full portfolio analytics platform. It is focused on adjusted cost base, capital gains reporting, and the review trail behind those numbers — including single-leg options transactions (buy/write, exercise, assignment, and expiry) — with CSV imports from all major Canadian brokerages: Interactive Brokers, Questrade, RBC Direct Investing, TD Direct Investing, CIBC Investor’s Edge, BMO InvestorLine, Scotia iTrade, and Wealthsimple.
Features not currently supported include cryptocurrency holdings, direct brokerage API sync, multi-leg options strategies (spreads, straddles, collars, and other combined positions), and complex corporate actions beyond splits and returns of capital.
Frequently asked questions
How does myCostBase calculate adjusted cost base in Canada?
myCostBase pools the cost of identical securities across every taxable brokerage held by the same tax owner, using the weighted-average method the CRA requires for identical property. It adjusts that pool automatically for FX conversion on USD trades, ETF return of capital and reinvested distributions, and options premium outcomes, so the running ACB reflects transactions from every account rather than one broker’s local book value.
Can I reconcile my T5008 slips with myCostBase?
Yes. T5008 Reconciliation and Reports covers comparing your calculated ACB and proceeds against the cost and proceeds figures reported on T5008 slips, so you can identify and resolve discrepancies before filing.
Do registered accounts like RRSPs or TFSAs affect my ACB pool?
No. Only taxable, non-registered accounts belong in the pooled ACB calculation. Getting Started covers marking each account as taxable or excluded during setup, which keeps RRSP, TFSA, FHSA, and RESP accounts out of scope.
What happens if I hold the same security at more than one brokerage?
Under the CRA’s identical property rule, one tax owner has one pooled ACB per security across all of their taxable brokerages, even though the brokers never share information with each other. Pooled ACB Across Brokerages covers this rule and the account-scope decisions that come up alongside it.
Does myCostBase handle USD-denominated trades?
Yes. USD and FX Conversion for Capital Gains covers converting foreign-currency trades to CAD using transaction-date Bank of Canada rates, so proceeds and ACB stay correct trade by trade instead of relying on a single annual average.