What Causes Error 450?
This error happens because the Canada Revenue Agency (CRA) does not allow EI overpayment claims for returns filed more than three years late. The claim becomes ineligible, and adjustments are required to proceed.
How to Resolve Error 450
To fix this error, adjust the CPP claims on your tax return as follows:
Locate Line 45000 (or 450 on 2018 and older returns) on your tax return.
(Tip: In the review section, go to “Your PDF” in the T1-General. This line is near the bottom.)Find the EI amount, typically on T4 Box 18.
Reduce your EI payment amount by the value shown on Line 45000 (or 450).
Verify that Line 45000 (or 450) now reflects $0.
Why This Matters
Resolving this error ensures your return is processed smoothly. While the EI overpayment cannot be claimed, correcting your return prevents further delays or complications with CRA processing.
Tip: Avoid this issue by filing your tax return within three years of the tax year to keep EI overpayment claims eligible.