I am looking at the summary before filing and the balance owing is different than the estimate at the top of the page by about $4K - what can cause this?

[CaliA1]

Hello there!
There are a few reasons why the balance owing on your final summary might differ significantly from the initial tax estimate at the top of the page. Some factors to consider include:
1. Updated or Additional Information – As you work through your return, you might add or update details such as additional income, deductions, credits, or tax instalments that weren’t fully factored into the initial estimate. The summary includes the complete, final data, which can change your balance significantly.
2. Rounding and Calculation Differences – Early estimates are sometimes rounded or use simplified figures, whereas the final summary uses precise amounts and accounts for all calculation nuances, which can result in differences.
3. Tax Credits and Deductions – Certain credits or deductions (especially income-tested ones) might not be fully reflected in the preliminary estimate. When they are finally calculated, they can shift the overall balance owing.
4. Provincial Differences or Additional Forms – If you’re filing both federal and provincial returns within TurboTax, final calculations on one may have adjustments that aren’t captured in the top summary estimate.
5. Errors or Incomplete Data – Occasionally, numbers might be missing or entered incorrectly in one section but later corrected when you review the summary. If you see a $4K difference, it could be due to an overlooked entry or a misapplied amount in an earlier step.

If the difference is unexpected, it’s a good idea to:
• Review your recent entries and ensure all information (income, deductions, credits, installments) is accurate and complete. 
• Navigate through TurboTax’s summary pages and look for any alerts or messages that highlight changes or adjustments made to your tax calculations. 
• Use the “print” or “view detailed calculation” options if available to help isolate which section may be causing the difference. 
• Consider using TurboTax’s built-in help or contacting the support if you continue to see discrepancies that you can’t explain.

Getting a clear understanding of where the change is coming from will help ensure your return is complete and accurate before you file. If you’re still unsure or if your numbers seem off, consulting with a tax professional or reaching out to TurboTax support can give you personalized guidance.
You can call customer support at 1-888-829-8608. During tax season (from CRA NETFILE opening (February 24, 2025) to the regular filing deadline (April 30, 2025), we're available 7 days a week during these hours:

• 9 AM to midnight ET for English support
• 9 AM to 9 PM ET for French support

During the rest of the year (up until February 23, 2025, and from May 1, 2025 to mid-February 2026, we're available Monday through Friday, 9 AM to 6 PM ET for English and French support.