A TD1 helps an employer calculate income tax deductions from your pay. It is not a tax return, and an amount entered on it does not establish your entitlement to a credit when you file.
Start with the right occasion and version
Complete the required TD1 when you begin a new job. Review it when a change affects your personal tax credits or when you want additional tax withheld. The CRA says a new form should be completed within seven days of a change that could reasonably affect those credits. You do not need to submit a new form every January if your circumstances have not changed.
Use the current federal form. The provincial or territorial form can also be required, including when you claim more than the basic personal amount for that jurisdiction. Ask payroll which forms apply to your employment situation; your mailing address alone does not settle every province-of-employment question.
Enter what you can support
Read the conditions beside each credit rather than treating every blank as something to fill. A partner's expected income or an amount already claimed at another employer can change the answer. Retain the figures used for your estimates, particularly when family income is uncertain.
For concurrent jobs, follow the multiple-employer instructions. See two jobs and withholding for the practical consequence of claiming credits twice.
Keep the form and check a pay statement
Submit the completed form to your employer, not as a substitute for filing with the CRA. Keep a copy and the date supplied. If you requested extra deductions, check that payroll applied them.
When your circumstances change again, update the estimate. A TD1 improves the timing of payments throughout the year; the annual return still reconciles your actual income, deductions and credits.
