How CPP is calculated
Service Canada calculates your CPP benefit from your contributory career — every year you contributed, the amount you earned that year as a percentage of the Year’s Maximum Pensionable Earnings (YMPE), and how many years you contributed. The maximum benefit at age 65 is paid only if you contributed the YMPE in 39 of your 47 best years between 18 and 65.
The actuarial adjustment
Take CPP before 65 and your benefit is reduced 0.6 % for every month early — 36 % less if you start at 60. Take CPP after 65 and your benefit is increased 0.7 % for every month late — 42 % more if you start at 70. These factors are designed to be roughly actuarially fair across the population: the typical Canadian receives the same lifetime total whether they start at 60 or 70, but the year-to-year cash flow differs sharply.
For a precise quote
Sign in to My Service Canada Account and view your CPP Statement of Contributions. It will show your projected benefit at 60, 65, and 70 based on your actual earnings record. This page’s estimate is informational only — it can be off by 10–20 % depending on how flat or volatile your career earnings have been.