For the 2018 tax year, you’re allowed to contribute the lesser of $26,230 or 18% of your earned income for the previous year. The maximum for the 2019 tax year is $26,500. If you made contributions to a pension plan, your room will be reduced accordingly. As well, if you have unused contribution room from previous years, those amounts carry forward indefinitely.
For more information about RRSPs, please see THIS LINK.