ACB Calculation
Weighted average cost method as required by CRA for publicly traded securities.
Canadian ACB Calculator
Free Adjusted Cost Base Calculator for Canadian Investors
Track your stock and options transactions, calculate Adjusted Cost Base following CRA rules, detect superficial losses, and generate tax reports for Canadian investors.
Options Support
Full support for options including exercise, assignment, and multi-leg strategy detection.
Superficial Loss
Automatic detection of superficial losses within the 61-day window.
Frequently Asked Questions
- What is Adjusted Cost Base (ACB)?
- Adjusted Cost Base is the total cost of an investment for tax purposes, including the purchase price plus commissions and other acquisition costs. In Canada, the CRA uses ACB to calculate the capital gain or loss when you sell a security.
- How is ACB calculated in Canada?
- For identical publicly traded shares, the CRA requires the weighted average cost method. Each purchase adds its total cost to the running ACB, and the ACB per share is the total ACB divided by the total number of shares held. Selling shares reduces the total ACB proportionally but does not change the ACB per share.
- What is a superficial loss?
- A superficial loss occurs when you sell a security at a loss and you (or an affiliated person) buy back the same or an identical security within 30 days before or after the sale, and still hold it at the end of that period. The CRA denies the loss and adds it to the ACB of the repurchased shares.
- Does StockACB follow CRA rules?
- StockACB calculates ACB using the CRA weighted average cost method and applies the superficial loss rule within its 61-day window. It is a calculation tool, not tax advice — verify results against your own records and consult a tax professional for your situation.
Want a deeper explanation with worked examples? Read the ACB guide for Canadian investors.