The spring tax marathon is finally behind us. With personal filing deadlines and the most common corporate filing deadlines officially in the rearview mirror, you might be tempted to shove your tax files into a drawer and forget about the Canada Revenue Agency (CRA) until next year.

However, before you completely check out, there is a brief—and highly valuable—post-filing window you shouldn’t ignore. Taking a few proactive steps right now can save you from unexpected interest charges, administrative headaches, and the dreaded scramble next spring.

Here is your essential post-filing to-do list:

1. Decode Your Notice of Assessment (NOA)

When your Notice of Assessment arrives, it is easy to glance at the final number, breathe a sigh of relief, and file it away. However, your NOA is packed with vital information and is the first place to spot a CRA discrepancy before it snowballs into a larger issue.

• Compare the bottom line: Check the assessed figures against the tax return you (or your accountant) actually filed. If the CRA has altered your balance owing or refund, look for the explanation provided on the NOA.
• Check your carry-forwards: Review your available RRSP contribution room, TFSA limits, and any carried-forward capital or non-capital losses. This is the exact data you will need for your 2026 tax planning.
• Act quickly on discrepancies: If the CRA has removed a deduction or changed your income figures, you generally have 90 days from the date on the NOA to file a Notice of Objection. Don’t wait until next year’s tax season to address a mistake made this year.

2. Handle Post-Filing Queries Without Panic

Seeing “Canada Revenue Agency” on a brown envelope in the middle of July is enough to spike anyone’s blood pressure. But take a deep breath: receiving a summer letter does not mean you are being audited.

During the summer months, the CRA conducts routine Processing Reviews and Matching Programs.

• What it is: They are usually just asking you to verify a specific claim by providing the supporting receipt or document (such as medical expenses, donation receipts, or corporate vehicle logs).
• How to respond: Respond professionally, completely, and—most importantly—by the deadline stated in the letter. Provide clear copies of the requested documents. Ignoring a simple request for a receipt is the fastest way to have a legitimate deduction denied, which will trigger a reassessment and a sudden tax bill.

(Pro-tip: provide precisely what the CRA has requested and avoid providing any extra information. Providing extra information may result in more questions and more digging by the CRA.)

3. Manage Tax Balances and CRA Interest

If your spring filings resulted in a corporate or personal tax bill that was higher than anticipated, burying your head in the sand will only make it more expensive. CRA interest rates on overdue balances are compounded daily and are surprisingly high right now.

• Explore payment arrangements: If you cannot pay the lump sum immediately, contact the CRA to set up a payment arrangement. While interest will still accrue, a formal arrangement prevents the CRA from taking aggressive collection actions, like freezing your corporate bank accounts or garnishing receivables.
• Prepare for installments: If your net tax owing was over $3,000 this year, you will likely be required to pay your taxes in quarterly installments moving forward. A higher-than-expected bill this spring means your upcoming installment requirements will also increase. Budget for this cash flow hit now so you aren’t caught off guard in September and December.

4. Upgrade Your ‘Paper Trail’ for 2026

Right now, the frustration of hunting down faded receipts, reconciling a messy corporate credit card, and dealing with the infamous “shoebox” is fresh in your mind. Harness that annoyance and use it as motivation to upgrade your systems for 2026.

• Go digital immediately: Ditch the paper. Implement a receipt-capturing app (like Dext or Hubdoc) that syncs directly with your cloud accounting software. When you incur a business expense, snap a photo on your phone and file the paper away.
• Separate business and personal: If you found yourself untangling personal expenses from corporate ones this spring, draw a hard line today. Ensure all business expenses strictly go through the corporate card and avoid co-mingling.  (During a review, co-mingling of expenses can lead to more questions and deeper digging by the CRA.  You also might be paying your bookkeeper extra for dealing with personal items that aren’t really related to the business.)
• Schedule monthly check-ins: Don’t leave a year’s worth of bookkeeping for next March. Block off one hour on the first Friday of every month to reconcile your accounts and categorize expenses. It turns a monumental spring mountain into a series of manageable monthly molehills.

The Bottom Line:

Tax season doesn’t truly end on filing day; it ends when your assessments are cleared, your balances are managed, and your systems are prepped for the year ahead. Taking care of these four steps now will make your summer much more relaxing—and your 2026 tax season infinitely easier.