Like all CPP contributions, contributions toward the PRB will be made only on annual earnings between a minimum amount of $3500 and a maximum amount that is set each year ($52500 in 2014). If you earned less than $3500 in 2014, you are not eligible to contribute to CPP. If you earned between $3500 and $52500 in 2014, your CPP contributions are based on your earnings. If you earned over $52500 in 2014, your CPP contributions are based on the maximum of $52500 set for this year.
The contribution rate is 4.95 percent for the employee and 4.95 percent for the employer. Self-employed individuals pay both portions, which makes for a contribution rate of 9.9 percent.
CPP contributions toward the PRB will be mandatory for working CPP retirement pension recipients up to age 65 and their employers. You can then opt out of making contributions or continue making contributions until you reach age 70 (your employer must contribute if you do). At age 70, CPP contributions can no longer be made.