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 taxpayer holds, then adjusting that pool for stock splits, ETF return of capital, DRIP reinvestment, and foreign exchange on USD-denominated trades. A broker statement or T5008 can be a useful cross-check, but one institution cannot see records held elsewhere, and CRA says Box 20 may or may not reflect the investor’s ACB. 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 taxpayer 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 transactions to CAD with documented rate sources and dates.
- 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.
Reference
Beyond the core workflow, these pages cover the rules behind the calculation and where myCostBase fits for different audiences:
- ACB Calculation Methodology — the pooling formula, documented FX conversion, ETF adjustments, and option rules behind the ledger.
- Supported Brokers — the Canadian brokerages myCostBase imports CSV history from.
- Product Limits and Scope — what myCostBase does not do, and what it’s built to do instead.
- myCostBase for Accountants — what a client’s export looks like from the accountant’s side.
What myCostBase does not do
myCostBase does not replace tax filing software and it does not try to be a full portfolio analytics platform — see Product Limits and Scope for the complete list of what’s in and out of scope, including crypto, direct brokerage API sync, and multi-leg option grouping. CSV imports are supported from all major Canadian brokerages — see Supported Brokers for the full list.
Frequently asked questions
How does myCostBase calculate adjusted cost base in Canada?
myCostBase pools identical securities across a taxpayer’s taxable brokerages using weighted-average cost. It records documented FX conversions, ETF cost-base adjustments, and option grant and resolution events so the ledger can be reviewed across accounts. See ACB Calculation Methodology for the formulas and tax-treatment details.
Can I reconcile my T5008 slips with myCostBase?
Yes. The Reconciliation and Reports guide 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 taxpayer generally has one pooled ACB per identical security under the same ownership across taxable brokerages. A brokerage may not have the taxpayer’s complete external history. 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 covers converting foreign-currency transactions to CAD with a documented Bank of Canada daily rate or supported override, while retaining the rate source and date used for each entry.