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A tax preparer is someone who fills in your return from the slips and receipts you hand over, then sends it to the CRA for a fee. Registered preparers use the CRA’s EFILE service to do that, but you’re still the one who answers for what’s on the return.
What does a tax preparer actually do?
They take your information and turn it into a return. That means entering slips, choosing which credits and deductions to claim, and sending the file. The CRA says preparers can be accountants, firms, organizations, discounters or certified individuals, so the label covers a lot of ground.
What a preparer can’t do is know things you didn’t tell them. A missed T5 or a forgotten medical receipt stays missed. That’s why the first hour of the job is really about you gathering paper.
Who is responsible if the return is wrong?
You are. Before an EFILE preparer files for you, you get a completed Form T183, and you have to check that its figures match your electronic return. Signing Part F is what authorizes the filing.
So don’t sign in a hurry. Read the totals. Do the income figures match your slips? Is the refund or the balance owing roughly what you expected? If it’s way off, ask why before the return goes anywhere.
Keep your records too. The CRA page on using a preparer says to hold on to them for at least 6 years.
What should you bring to a tax preparer?
Bring the boring things, all of them:
- Every tax slip you received (T4, T4A, T5 and the rest)
- Receipts for anything you plan to deduct or claim as a credit
- Last year’s notice of assessment
- Your direct deposit and mailing details, updated with the CRA first
Updating your address and bank details in advance saves a refund from going astray. It takes five minutes.
Do you need a tax preparer for a simple return?
Often not. Take a single Ontario employee earning $45,000 with only a T4. Our 2026 estimate is $5,243.01 of income tax, $3,202.75 of CPP and EI, and $36,554.24 left. You can reproduce that yourself with the income tax calculator, and certified software follows the same rules.
Things change when the return has moving parts. Self-employment is the obvious one. On $60,000 of net self-employed income in Ontario, the estimate is $7,879.42 of income tax and $6,723.50 of CPP, because you pay both halves. The self-employed tax calculator shows the split. That estimate leaves out EI and ignores business expenses, so treat it as a starting point for the conversation.
A rental property, a sale of shares, foreign income or a death in the family are the other cases where a preparer earns their fee. We can’t say what that fee is, because we found no official figure for it. Ask for it in writing before you hand over anything.
Mistakes people make with a preparer
The biggest one is treating the preparer as the responsible party. The second is choosing on speed alone, especially when a refund is being advanced to you. If a firm offers cash today for your refund, it’s a discounter, and different rules apply. The CRA’s page on discounters spells them out.
Another one: not looking at credits. The tax credits calculator takes a few minutes, and if a credit you expected isn’t on the return, you can ask about it. And once the return is filed, the tax refund calculator gives you a rough check on the result.
Where do these numbers come from?
The description of what preparers do, Form T183 and the six year record rule come from the CRA page on using a professional tax preparer. The example figures come from our calculators, built on 2026 CRA rates rechecked on 29 September 2026. This website has no connection with the CRA or any other government body.
Frequently asked questions
What does a tax preparer do?
They complete your return from your slips and receipts and send it to the CRA, usually through EFILE, for a fee.
What is Form T183?
It's the form your EFILE preparer gives you to authorize filing. The figures on it must match your electronic return, and signing Part F approves the filing.
How long should I keep my tax records?
The CRA says to keep them for at least 6 years.
Can I file a simple return without a preparer?
Yes. CRA certified software or SimpleFile can handle a return with a few slips, and the rules are the same either way.
Who is responsible if my preparer makes a mistake?
You review and approve the return before it's filed, so you're the one who answers to the CRA. Check the totals against your slips first.
- How to choose a tax preparer in Canada
How to decide if you need a tax preparer, what a preparer does, the questions to ask before you hire one and where to find free help in Canada
Information only. This page is general information, not tax, legal or accounting advice. Tax-Services.ca is an independent publisher: we don't prepare or file tax returns or offer tax services, and we have no connection with the CRA, Revenu Québec, any government or any company named on this page. Check the figures that matter with an official source or a qualified professional.