A tax dispute is any disagreement between you and the CRA over what you owe. That can look different depending on your situation.
Sometimes it starts with an audit. The CRA selects your return for review, often because something flagged in their risk-assessment system, and an auditor asks to see your books, bank statements, and supporting records. If the auditor decides you underreported income or overclaimed deductions, they issue a reassessment. That reassessment changes your tax bill, sometimes by a lot.
Other times, a notice of assessment just doesn’t look right. A legitimate deduction gets denied. A credit disappears. Interest and penalties start compounding on a balance you don’t believe you owe. The CRA charges 7% annual interest on overdue tax as of Q2 2026, and it compounds daily, so the longer a disputed amount sits unresolved, the more expensive it gets.
That’s when many business owners freeze. Or worse, ignore it. Both are costly mistakes, because the CRA has strict deadlines baked into the dispute process.
When the CRA is asking questions about your business, you want people on your side who’ve dealt with this before, and who know the tax rules inside and out. Our team brings the right mix of technical depth and hands-on experience to get your dispute resolved.
Cassar CPA Professional Corporation
Cassar CPA Professional Corporation
Cassar CPA Professional Corporation
Cassar Business Services Inc.
Where you are in the process determines how we approach it. If the CRA has just contacted you about an audit, the work starts immediately. We review the audit letter, figure out what they’re looking at, organize your records, and respond so that your position is documented clearly from day one. We deal with the auditor directly.
Every piece of information you give a CRA auditor matters. Mistakes, even honest ones, get used against you. We prepare your response, handle follow-up requests, and make sure nothing falls through the cracks
Disagree with a reassessment? You have 90 days from the date on the notice to file a formal Notice of Objection under section 165 of the Income Tax Act (or section 301 of the Excise Tax Act for GST/HST matters). Miss that deadline and your options shrink fast. We draft and file the objection, outlining the facts and the legal basis for your position. The CRA’s Appeals Division then reviews the case independently of the original auditor.
The CRA has discretion to cancel or reduce penalties and interest when circumstances beyond your control prevented you from meeting your tax obligations. Filing a taxpayer relief request using Form RC4288 can make a real difference, but the application needs to be well-documented and clearly argued. We handle that from start to finish.
Realized you’ve got errors in past filings, unreported income, missed returns, incorrect deductions? The CRA’s Voluntary Disclosures Program may help you correct the record with reduced penalties. The program was overhauled in October 2025 under IC00-1R7 and now distinguishes between “prompted” and “unprompted” applications. Come forward before the CRA contacts you and you could receive 100% penalty relief and up to 75% interest reduction. We assess whether you qualify and prepare the application.
Tax disputes are stressful and time-sensitive. The wrong response, or no response, can turn a manageable issue into a much bigger problem.
Our founder, Matt Cassar, CPA, has spent over fifteen years working with small business owners, professionals, and incorporated entrepreneurs across the GTA. Matt has guided hundreds of clients through CRA audits and reassessments. That experience matters when the CRA is on the other side of the table.
We’re not a law firm, and we’re upfront about that. If your dispute involves allegations of fraud, potential criminal liability, or requires representation in court, we’ll refer you to a qualified tax lawyer. But for the vast majority of audits, objections, and penalty relief requests, the situations most small business owners actually face, a CPA with deep tax experience is exactly who you need.
CRA audits are rarely random. The agency’s risk-assessment systems compare your return against industry benchmarks, prior-year filings, and third-party data like T4s, T5s, and information slips from other businesses. A few things draw their attention more than others.
Inconsistent revenue between your income tax return and your GST/HST filings is a big one. If your T2 shows $150,000 in revenue but your GST/HST return only reports $110,000 in taxable supplies, that mismatch gets flagged electronically before a human ever looks at it.
Expenses that don’t match your revenue profile. Meals, entertainment, vehicle claims, home office deductions, the CRA benchmarks your ratios against similar businesses in your industry. If yours are out of line, expect questions.
Repeated losses year after year. At some point, the CRA will ask whether your activity is a genuine business with a reasonable expectation of profit.
Personal expenses running through the corporation. Amounts that can’t be clearly tied to business operations risk being reclassified as taxable shareholder benefits under the Income Tax Act.
None of this necessarily means you did anything wrong. It means you need proper records and a clear explanation ready. That’s exactly where having a CPA with audit experience matters.
You have 90 days from the date on your notice of assessment or reassessment to file a Notice of Objection. Individuals also get an extended window: the later of that 90-day period or one year from the filing due date. For GST/HST disputes, the deadline is strictly 90 days from the notice. If you miss it, you can apply for an extension under section 166.1 of the Income Tax Act, but approval isn’t guaranteed.
For most audits, reassessments, and objections, a CPA with tax dispute experience can handle the process from start to finish. You’ll want a tax lawyer if your situation involves allegations of fraud, criminal liability, or if the matter reaches the Tax Court of Canada. At Cassar CPA, we’re straightforward about where that line is. If you need a lawyer, we’ll tell you and help you find one.
No. You don’t have to pay the disputed amount while a Notice of Objection is under review or while an appeal is before the Tax Court. But interest continues to accrue at the prescribed rate-currently 7% for Q2 2026, compounded daily. If the dispute is resolved in the CRA’s favour, you’ll owe that interest on top of the original balance.
The VDP lets you come forward to correct errors or omissions in past tax filings-things like unreported income, unfiled returns, or incorrect deductions. If you apply before the CRA contacts you about the issue, you can receive 100% penalty relief and up to 75% interest reduction. The program was updated in October 2025 with broader eligibility rules. It’s not available if you’re already under audit or investigation for the same issue.
It depends on the complexity. A straightforward response to an audit review costs less than a multi-year objection with significant dollar amounts at stake. At Cassar CPA, we’ll give you a clear picture of what’s involved after we review the CRA correspondence. No surprises.
“Their diligent approach and personal care have saved me thousands of dollars in taxes over the years!”
"You simply won’t get this quality of service from a big firm.”
“I’ve been working with Matt for a while now and I recommend him as much as I can to my friends and family”
“Cassar CPA has saved me a lot of time, money, and headache!”
“We love Matt and his team! We use them for our NFP organization and they’re always fast, flexible, and knowledgeable”
“Fantastic and knowledgeable team with very forward thinking practices.”
"Matt and his team provide clients efficient and speedy turnaround on monthly accounting and year-end services, while at the same time acting as an advisor on various finance matters.”
If you’ve received a CRA audit letter, a reassessment you disagree with, or you’re dealing with penalties and interest that feel unfair, the worst move is to wait. Deadlines in tax disputes are strict-once they pass, your options narrow. Book a discovery meeting with our team and let’s figure out what we’re dealing with. From our offices in Toronto and Oakville, we serve business owners across the Greater Toronto Area and beyond.
Cassar CPA Professional Corporation works with small business owners, incorporated professionals, and entrepreneurs from our offices in Toronto (WaterPark Place, 20 Bay Street) and Oakville (132 Trafalgar Road). We serve clients throughout the Greater Toronto Area, including:
Toronto · Oakville · Mississauga · Brampton · Vaughan · Markham · Richmond Hill · Etobicoke · Burlington · Milton · Halton Hills · Other GTA & Halton Region Communities
Toronto Office
WaterPark Place 20 Bay Street, 11th Floor
Toronto, ON M5J 2N8
