Updated Checked by the Tax-Services.ca editorial team How we check
The TD1 Ontario job is really two forms. You fill in the federal TD1 and the provincial TD1ON, and your employer uses both to decide how much income tax to hold back from each cheque. Skip them and you’re taxed as if you had only the basic personal amount, which is $16,452 federally and $12,989 for Ontario in 2026.
Which TD1 forms does an Ontario employee fill in?
Two of them, and they’re separate documents on the CRA site. The federal TD1 covers federal credits. The TD1ON covers the Ontario ones. You’ll find both on the CRA’s TD1 personal tax credits returns page, which has a section for 2026 forms. Your employer wants both when you start, and again within 7 days of a change that affects your credits, such as a new dependant or a spouse who stops earning.
Nobody sends them to the CRA. The forms go to payroll, who keep them on file. Their only job is to set withholding, so a mistake here doesn’t change what you actually owe. That gets settled when you file your return.
What if you skip the forms?
Your employer then deducts tax using the basic personal amount only. For plenty of people that’s fine. If you’re a single worker with no other claims, the form would just repeat the basic amount anyway. It’s the people with extra credits who lose out, because they overpay all year and wait for a refund in spring.
| Item, 2026 | Amount |
|---|---|
| Federal basic personal amount, maximum | $16,452 |
| Federal basic personal amount, minimum | $14,829 |
| Ontario basic personal amount | $12,989 |
| Ontario lowest tax rate | 5.05% |
| Ontario indexing for 2026 | 1.9% |
| Days to hand in a new form after a change | 7 |
How much does an extra claim change your pay?
Take someone earning $60,000 in Ontario. With only the basic amounts, federal tax comes to $6,192.73 and Ontario tax, including the health premium, to $3,224.52. That’s $9,417.25 in total.
Now add a $5,000 credit amount on the forms. Total tax falls to $8,464.75, so the claim is worth $952.50 a year. Spread over 26 pay periods, that’s roughly $36.63 more in each cheque. Small, but it’s your money and it arrives on time instead of in April. Think of it as a couple of extra coffees a week, and the double-double is on the taxman.
The tax credits calculator gives a feel for what credits are worth, though it’s federal only. To see the effect on a paycheque, the take-home pay calculator is the quicker tool.
What should you do when your life changes?
Give payroll a fresh form. Sam starts a part-time program at a college in London, Ontario, and his partner picks up a full-time job. Both facts can change which amounts either of them should claim, and neither employer will know unless the forms say so. The rule of thumb: if you’d mention it to a friend as big news, it probably touches a TD1.
You don’t have to guess the figures. Each form walks you through the lines, and a mistake only changes withholding, not your final bill. If you aren’t sure how to fill one in, a tax professional you hire yourself can look at your case, since this site doesn’t give personal advice.
Two jobs, and the box that matters
If you work for two employers at once, you can’t claim the same credits twice. On the federal TD1, the second employer’s copy has a box to tick, and you enter 0 on line 13 and leave lines 2 to 12 blank. Do the same on the TD1ON with the matching box.
Is that a hassle? A bit. But it stops the second job from under-withholding, which is what catches people at filing time. If your two jobs together put you in a higher bracket, ask payroll about extra tax at source, or check your marginal tax rate before you decide.
Mistakes that cost money
The common one is never updating the form. You have a child, a partner’s income drops, you go back to school, and payroll still works from the old page. The second is claiming amounts that belong to a spouse who already claimed them.
Also remember that Ontario’s health premium and surtax aren’t claimed on either form. They’re worked out separately. Near $72,000 and $200,000 the premium climbs quickly in narrow bands, which is why the income tax calculator shows steeper jumps there. We haven’t tested every payroll system, so what your employer’s software does with the forms may differ in small ways.
Sources, and how we checked them
The basic personal amounts, the 2026 indexing and the Ontario rate come from the CRA‘s 2026 payroll deductions tables for Ontario and the TD1 form pages. The 7 day rule comes from the CRA page on getting TD1 forms from employees. We ran the worked example through the site’s own maths for 2026. This site isn’t connected to the CRA or the Ontario government, and the pay-period figure assumes 26 cheques.
Frequently asked questions
Do I need both the TD1 and the TD1ON?
Yes, if you work in Ontario and claim anything beyond the basic personal amount. Your employer keeps both forms and uses them to set withholding.
What happens if I don't hand in a TD1?
Your employer deducts tax using only the basic personal amount. You may overpay during the year and get the difference back when you file.
How soon must I hand in a new form?
Within 7 days of a change that could alter your credits, according to the CRA page for employers.
What is the Ontario basic personal amount for 2026?
$12,989, indexed by 1.9% for 2026.
Do I send the TD1ON to the CRA?
No. Give it to your employer and keep a copy. It only sets how much tax comes off each cheque.
- How to file your tax return in Canada: steps and dates
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- Ontario income tax and sales tax in 2026
How Ontario income tax works in 2026: the five brackets, the surtax and health premium, the 13% HST, and the calculators that switch to Ontario