The TD1 Personal Tax Credit Return is a form used to determine the amount of tax to be deducted from an individual’s employment income or other income, such as pension. In addition to the federal TD1 form, there are also provincial ones specific to each province.
You’re required to complete the TDI forms when:
Sign and date the forms and give them to your employer who uses them to determine the amount of tax to deduct from your paycheque. If you’re a permanent resident of Canada, you can claim these returns.
You don’t have to complete a new TD1 every year unless there’s a change to your eligibility for federal, provincial or territorial personal tax credit amounts.
If you do not complete a TD1, then your employer or payer will deduct taxes based on you claiming only the basic personal amount. If you have more than one employer and claimed personal tax credit amounts on another TD1, you cannot claim them again.