Paycheck Boost (T1213) Calculator
Estimate your increased monthly cash flow in 2026 by reducing tax withholding at source.
Last updated: April 2026
What is a T1213?
By default, your employer calculates your taxes as if you have no deductions. If you contribute $1,000 a month to an RRSP, you'll eventually get a big refund, but you're giving the government an interest-free loan in the meantime.
CRA Form T1213 allows you to ask the CRA to give your employer permission to deduct LESS tax from your paycheck right now, based on the deductions you'll claim at year-end.
How to use this calculator
- 1Estimate Annual Deductions — Include your planned RRSP deposits, childcare expenses, and any investment interest paid.
- 2Calculate the Boost — See exactly how much your bi-weekly or monthly paycheck will increase.
- 3File with CRA — You must file this form every year, ideally in November or December for the upcoming year.
Formula & example
Monthly Boost = (Total Annual Deductions × Marginal Rate) / 12
If you contribute $24,000/year to an RRSP and your tax rate is 40%, you save $9,600/year. A T1213 approval adds $800 per month directly to your take-home pay.
Benefits
Improved Cash Flow
Have the money in your pocket throughout the year for bills or reinvesting.
Dollar Cost Averaging
Reinvest your 'refund' every month to get more time in the market.
Interest-Free Government Loan
Stop lending money to the government for 0% interest.
Use cases
Recurring RRSP Savers
If you have a monthly auto-deposit, this tool is vital for your efficiency.
Parents
Childcare expenses are a major deduction that can stay in your wallet month-to-month.
Frequently asked questions
When should I file?+
Ideally in late autumn (Oct-Nov) so that it is approved by your employer's first January paycheck.
What if my employer has a Group RRSP?+
If your RRSP contributions are taken directly from your pay by your employer, you don't need a T1213—they already reduce the tax at source!