Most missed claims have no slip reporting them to the Canada Revenue Agency (CRA), so nothing on your return prompts you. This guide takes each claim for employees, families, students and retirees in turn: who qualifies, the 2025 amount, the return line and the proof to keep. It leaves out business expenses, and claims tied to buying or renovating a home or to property taxes, such as the home accessibility tax credit.
Key Takeaways
- A deduction lowers your taxable income, while most credits are worth the lowest federal rate: 14.5% for 2025 and 14% for 2026, plus a provincial or territorial credit.
- You choose the 12-month window for medical costs, and the lower-income spouse often gets more from the same receipts.
- Once the CRA approves the disability amount, it can adjust your returns for up to 10 years.
- By our reading of the 10-year rule, a change request for 2016 has to be made by December 31, 2026.
How a Deduction and a Tax Credit Reduce Your Personal Income Tax
Tax deductions and tax credits both reduce the amount of tax you pay, in different ways. A deduction comes off your income before tax is calculated, so for 2025 it saves federal tax at a rate between 14.5% and 33%, depending on your income.
Non-refundable tax credits are amounts that reduce your federal tax at the lowest federal rate, whatever your bracket. That rate fell from 15% to 14% on July 1, 2025, which makes it 14.5% for 2025 and 14% for 2026. Credits help a modest earner as much as a high earner, provided there is tax to reduce. They can reduce your tax to zero, but they never create a refund.
Most federal credits also have a provincial or territorial counterpart with its own amounts. Ontario’s disability amount for 2025 is $10,298, for example, against $10,138 federally, and Quebec residents claim theirs on a separate Quebec return.
Example. By our arithmetic, a $1,000 credit amount is worth $145 of federal tax for 2025 and $140 for 2026, while deducting $1,000 saves $205 in the 20.5% federal bracket ($57,375 to $114,750 for 2025).
Deductions Canadians Often Miss at Work
Canada employment amount (line 31260). If you report employment income on line 10100 or 10400 and are not self-employed, you claim the lesser of that income and $1,471 for 2025, or $1,501 for 2026. Your T4 slips are the proof. The CRA’s table of indexed amounts lists both years for the indexed figures in this guide.
Union and professional dues (line 21200). You can deduct annual union dues, professional board dues required under provincial or territorial law, and the liability insurance or membership dues needed to keep a professional status recognized by law. Initiation fees, special assessments and pension plan charges do not qualify. Box 44 of your T4 shows dues your employer withheld, while dues you paid yourself appear only on the organization’s receipt. Claim each amount once.
Tradesperson’s tools (line 22900). An employed tradesperson or apprentice can deduct new tools, including the sales tax paid, that the employer certifies on Form T2200 as necessary for the job. Phones and other electronic communication devices do not count. For 2025, the amount you can claim is the lesser of $1,000 and the amount by which your tool costs, up to your employment income as a tradesperson, exceed $1,471. You report it on Form T777 and keep the receipts and the T2200.
Example. Jordan, an employed apprentice electrician earning $48,000, buys $2,600 of new tools in 2025 and his employer signs the T2200. His costs exceed $1,471 by $1,129, so the $1,000 ceiling applies. At his 14.5% federal rate, that claim saves $145 of federal tax by our arithmetic, plus a provincial saving. Had he spent $1,400, he could claim nothing.
Employees who work from home need a signed T2200 and the detailed method, since the temporary flat rate method does not apply to 2023 and later years; see our home office expenses guide. Teachers and early childhood educators get a refundable credit of 25% on up to $1,000 of school supplies for 2025, covered in our teacher school supply tax credit post. If you moved at least 40 kilometres closer to a new job or school, our guide to moving expenses sets out the available deductions.
Medical Expense Claims for You and Your Dependants
You can claim eligible costs paid in any 12-month period ending in 2025 that you did not claim for 2024, so one window can capture bills on both sides of New Year’s. The total is reduced by the lesser of 3% of your net income and $2,834 for 2025, or $2,890 for 2026. By our arithmetic, the dollar figure only takes over once your income passes about $94,467.
Line 33099 covers you, your spouse or common-law partner and your children under 18. Line 33199 covers other relatives who depended on you for support, such as an adult child or a parent, and there the 3% test uses the dependant’s income rather than yours. The CRA notes that it may be better for the lower-income spouse to claim. When we review past returns for new clients, a parent’s or adult child’s medical costs are one of the most commonly skipped claims, because families assume only the patient can claim them.
Keep receipts showing who was paid, plus any prescription or certification an item needs. Travel counts too. If you had to travel at least 40 kilometres one way for care not available near home, public transportation costs qualify, and at 80 kilometres, accommodation, meals and parking are added. The CRA’s page on lines 33099 and 33199 has the details.
Example. For 2025, Maya’s income on line 23600 is $31,000 and Daniel’s is $92,000. From October 2024 to September 2025 they paid $4,200 of eligible costs, none of it claimed for 2024. If Daniel claims, his 3% is $2,760, leaving $1,440 and a federal credit of $208.80. If Maya claims, her 3% is $930, leaving $3,270 and a credit of $474.15, provided she has that much federal tax to reduce. By our arithmetic at 14.5%, the same receipts are worth $265.35 more on her return, before the provincial credit.
The Disability Tax Credit and How Far Back It Reaches
You may qualify if a medical practitioner certifies on Form T2201 that you have a severe and prolonged impairment, significant limitations in two or more categories, or therapy to support a vital function. An impairment is prolonged if it has lasted, or is expected to last, at least 12 months.
For 2025 the federal disability amount is $10,138, worth $1,470.01 of federal tax by our arithmetic, and a child under 18 adds a supplement of up to $5,914. For 2026 the figures are $10,341 and $6,032. You claim the amount on line 31600 of your income tax return. If the person has too little tax liability to use it all, a supporting relative may be eligible to claim the rest on line 31800, or a spouse on line 32600.
Approval is where the money is. The CRA can adjust your returns for up to 10 years if you were eligible but did not claim. It reassesses those years itself if you ticked the box on the application asking it to. Otherwise, ask in writing or change each return online.
The Canada Caregiver Credit for an Infirm Relative
The CRA calls it the Canada caregiver amount, and it applies when a relative depends on you for support because of a physical or mental infirmity. For 2025, you claim $2,687 on line 30500 for an infirm child under 18. For an infirm dependant 18 or older, such as a parent, a sibling or an adult child, you are able to claim up to $8,601 on line 30450. That amount shrinks once the dependant’s income on line 23600 passes $20,197 and is gone at $28,798. For 2026, the two amounts are $2,740 and $8,773.
Relatives other than a child or grandchild must have lived in Canada at some time in the year. You cannot claim line 30450 for a person that you or someone else claims on line 30300 or 30400, because an infirm spouse or eligible dependant goes through those lines and line 30425 instead. Keep a practitioner’s signed statement of when the infirmity began and how long it is expected to last, because the CRA may ask for it. If you are eligible for the Canada caregiver amount for a parent, check line 33199 for that parent’s medical costs as well.
If you paid someone to look after a child so you could work or go to school, you claim those child care expenses on your tax return on line 21400 with Form T778. Our guide to child care expense claims covers the limits and which parent claims.
Student Loan Interest and the Tuition Tax Credit
Student loan interest (line 31900). Only the borrower can claim this credit, even when a parent paid the interest. The loan must come from the Canada Student Loans Act, the Canada Student Financial Assistance Act, the Apprentice Loans Act or a similar provincial or territorial law, and it must not have been combined or renegotiated with another loan. You can claim interest paid in 2025 or the previous five years if not yet claimed, and carry unused interest forward five years when you have no tax payable.
Federal Canada Student Loans and Canada Apprentice Loans stopped charging interest on April 1, 2023, a change Employment and Social Development Canada said would save the average borrower $520 a year at the rates of the time. The claim now centres on earlier interest and on provincial or territorial loans that still charge it, so keep the lender’s statements.
Tuition. A student first uses the federal tuition amount to bring their own tax to zero. The student can then transfer up to $5,000 of the current year’s amount, minus what they used, to a spouse or common-law partner, a parent or a grandparent. Anything left carries forward for the student alone, must be used in the first year they owe income tax, and can never be transferred later. The proof is Form T2202 from the school.
Commonly Overlooked Tax Claims for Investors and Donors
Carrying charges (line 22100). You can deduct most interest on money you borrowed to try to earn investment income, such as interest and dividends, and fees to manage your investments or for certain investment advice. Interest on money borrowed for an RRSP, TFSA or FHSA contribution is not deductible, and neither are safety deposit box charges or brokerage commissions. Tax preparation fees count only if you have business or property income. Keep loan statements that show the interest and what the borrowed money bought.
Charitable donations (line 34900). You or your spouse or common-law partner can claim gifts to registered charities and other qualified donees, so a couple can pool receipts on one return. The claim is capped at 75% of net income, and gifts can be held back for any of the next five years. Pooling matters because only the first $200 a year gets the lowest rate, 14.5% for 2025, while the rest earns 29%, or 33% at the highest incomes. Report gifts on Schedule 9 and keep the official receipts.
Example. Nadia and Omar each gave $300 in 2025. Claimed separately, each gets $29 on the first $200 and $29 on the last $100, for $116 between them. Pooled on one return, the first $200 earns $29 and the other $400 earns $116, for $145. By our arithmetic, pooling adds $29 of federal credit.
Pension Income Splitting: a Deduction for One Spouse, Income for the Other
You and your spouse or common-law partner can jointly elect to move up to 50% of your eligible pension income to the other, which can even out the household’s tax burden. The transferring spouse deducts the split on line 21000, the receiving spouse reports it on line 11600, and tax withheld follows in the same proportion. You both sign Form T1032.
The taxable part of a life annuity from a pension plan qualifies at any age. RRIF, life income fund and RRSP annuity payments qualify from age 65, or earlier after a spouse’s death. Old Age Security, Canada Pension Plan and Quebec Pension Plan benefits never qualify.
Eligible pension income also supports the pension income amount on line 31400, up to $2,000 federally for 2025, with provincial and territorial amounts from $1,000 to $2,000 (Ontario’s is up to $1,762). A split can give eligible pension income to a spouse who has none, so the household may claim the amount twice and lower the combined tax they pay. Run the split both ways, since the tax benefits shift with each spouse’s income.
Northern Residents Deductions and a Tax Credit That Has Ended
Northern residents (line 25500). If you lived permanently in a prescribed northern or intermediate zone for at least six consecutive months, Form T2222 lets you claim a daily residency amount and travel costs. For 2025, the northern zone allows $11 a day, plus $11 more if you are the only person in your home claiming it, and the intermediate zone allows half those rates. Travel covers up to two non-medical trips a person each year and any number of medical trips, limited by your employer’s travel benefit or a $1,200 standard amount, your actual costs and the lowest return airfare. Keep receipts for at least six years.
Digital news subscriptions (line 31350). This credit has ended. It applied only to 2020 to 2024, on up to $500 a year for a digital subscription to a qualified Canadian journalism organization, and it cannot be claimed for 2025 or later. An unclaimed subscription from those years can still be added by changing that year’s return.
How to Claim a Deduction You Missed in a Previous Tax Year
Wait for your notice of assessment, then pick a route. Change my return in your CRA account and ReFILE in certified tax software are processed within about two weeks, but Change my return cannot reach 2015 or earlier, and ReFILE cannot change a year before 2021. Otherwise, mail Form T1-ADJ with documents supporting the whole amount and allow about 16 weeks, or up to 33 weeks for a complex request. The CRA’s page on how to change your return compares the routes.
The limits sit in the Income Tax Act (ITA). An individual’s normal reassessment period ends three years after the original notice of assessment. After that, subsection 152(4.2) still lets the CRA refund tax or reduce what you owe if you apply within 10 calendar years after the end of the year, although the decision is discretionary. Subsection 164(1.5) sets the same window for a refund on a late return, and the CRA cannot issue a tax refund for a change requested beyond it.
By our reading, December 31, 2026 is the last day to apply for a change to 2016, or to file a 2016 return you never filed and still get a refund. The same three-year period limits the CRA too, as our post on when a year becomes statute-barred explains.
Common Tax Mistakes With Missed Deductions
- Claiming the family’s medical costs on the higher earner’s return by habit.
- Treating the medical window as the calendar year, so last autumn’s bills go unclaimed.
- Getting disability approval without asking the CRA to adjust earlier years.
- Deducting interest on money borrowed for an RRSP, TFSA or FHSA contribution.
- Claiming union dues twice, once from the T4 and again from the union’s receipt.
- Carrying tuition forward when a parent could have used this year’s transfer.
Your Action Checklist for Tax Filing
Most of these claims recur, so a short routine before you file your taxes saves a change request later.
- Compare every 12-month medical window ending in the year, on both spouses’ returns.
- List each relative who depends on you, and check lines 33199, 30450 and 30500 for each one.
- Apply for the disability amount if an impairment has lasted, or is expected to last, at least 12 months.
- Gather the dues receipts your T4 does not show, and a signed T2200 for tools or a home office.
- Run pension splitting both ways if either spouse has eligible pension income.
- Keep one folder of receipts through the year instead of scrambling at tax time.
- Review 2016 onward, and send any 2016 request by December 31, 2026.
Frequently Asked Questions
What do people forget to claim on taxes?
The claims people leave off are usually the ones no slip reports: medical travel, dues paid outside payroll, interest on investment loans and costs paid for a relative. Retirees can miss pension splitting, and students can lose track of tuition they could transfer. In our practice, a dependant’s medical costs and the disability amount are the largest, because both can reach back years.
What if I missed a deduction on my taxes?
Ask the CRA to change that year’s return once you have its notice of assessment: through Change my return, through ReFILE for 2021 and later, or on Form T1-ADJ by mail. You can apply for any of the previous 10 calendar years. By our reading of the Act, a request for 2016 must be made by December 31, 2026.
Why didn’t I see any difference on my tax return when I included my medical expenses?
The total is reduced by the lesser of 3% of your income and $2,834 for 2025, so a small total can produce no credit. The credit is also non-refundable, so if other credits already brought your tax to zero, it adds nothing. A different 12-month window, or a claim by the lower-income spouse, often changes the result.
What can I do with tuition amounts I don’t need this year?
First, use enough to bring your own tax to zero. You can then transfer up to $5,000 of this year’s federal amount, minus what you used, to a spouse or common-law partner, a parent or a grandparent, or carry the rest forward. A carried-forward amount stays with you and must be used in the first year you owe income tax.
What are the biggest tax loopholes in Canada?
Most of what people call loopholes are ordinary rules used with care: choosing the medical window, pooling donations, splitting pension income and transferring tuition. These are legitimate tax strategies written into Canadian tax law, not gaps in it. Anything sold as a loophole beyond that deserves a second look from a tax expert.
How long should I keep receipts for these claims?
Keep your records and supporting documents for at least six years from the end of the year they apply to, including receipts, cancelled cheques and bank statements that back up a claim. You do not send them with an electronic return, but the CRA can ask to see them later.
The Bottom Line on Overlooked Deductions and Credits
Missed claims are usually small in a single year and large across a decade.
- Most credits are worth 14.5% federally for 2025 and 14% for 2026, plus a provincial or territorial credit.
- Apply for disability approval early, since it can reach back 10 years.
- Start before tax season, and look back to 2016 while that year is still open.
Most households have more credits available than a slip-driven return shows, and the reliable way to maximize your tax savings is to check each claim against your own family every year. Our personal tax team can review past returns for credits and deductions you missed and file the change requests, and our tax planning advice sets up the year ahead. Contact us before December 31 if 2016 is on your list.
