Made a mistake on your tax return? Don’t worry. It happens to lots of people. Maybe you forgot a T4 slip, missed your RRSP contributions, or typed the wrong number. The important thing is to fix it as soon as you can.
Mistakes can affect your refund or cause you to owe more tax, which may lead to interest, penalties, or even a review from the CRA (Canada Revenue Agency).
Why You Should Fix Tax Mistakes Quickly
Even small mistakes can lead to:
- Delayed tax refunds
- Extra interest or late payment charges
- CRA reviewing or reassessing your return
- Losing tax benefits or getting fined (in serious cases)
The sooner you fix it, the better.
How to Fix a Mistake on Your Tax Return (For Individuals)
The CRA offers three ways to correct your return, depending on how you filed and what the mistake is:
1. ReFILE (Online – for simple fixes)
If you filed online using tax software and already received your Notice of Assessment from the CRA, you may be able to use ReFILE to make quick changes.
- For personal tax returns (T1) filed online
- Use CRA My Account or the same tax software
- Usually works for this year and the past couple of years
- Good for simple changes like adding a T-slip or fixing your RRSP number
- Important: You must wait until the CRA finishes your original return before using ReFILE
2. T1 Adjustment Request (Form T1-ADJ)
If ReFILE doesn’t work for your case, or if you filed your taxes on paper, you can send in a T1 Adjustment Request.
- Can be submitted online through CRA My Account, or by mailing the paper form
- You can fix tax returns from past years too
- You’ll need to include documents to support the changes (like updated T4s, medical receipts, etc.)
Tips: Paper file can take longer to process.
3. Voluntary Disclosures Program (VDP)
If you didn’t report some income, or made big mistakes over several years, you may need to apply to the CRA’s Voluntary Disclosures Program (VDP).
- This is for more serious errors that could lead to fines or penalties
- You must apply before the CRA contacts you
- If accepted, the CRA may reduce or cancel penalties and interest
- For example: unreported income, false claims, etc.
Tip: This process is more complex — it’s best to speak with a tax expert before applying
How to Avoid Tax Mistakes in the Future
- Keep your documents in one place: T4s, receipts, CRA letters, etc.
- Use certified tax software: It helps check for missing info or mistakes
- Review everything before you submit: Check your income, SIN, marital status, etc.
- Start early: Don’t leave it to the last minute
- Get help for complex taxes: Like if you’re self-employed or have investment income
Got tax questions? Want to save more money? Book your FREE 30-minute consultation now!