This article only applies if you have an amount in boxes 78, 79, 80, 81, 82, or 83 of your T4.

Sometimes, slip issuers make mistakes when filling out T4s. To help you avoid an audit, we check to make sure your slip is completed properly before you file your return.

Your employment code in box 29 is mandatory for CPP calculation purposes. Find the correct code.

If you have an amount in box 18 (EI premiums withheld), you must include an amount in box 24. Here are the CRA’s instructions for slip issuers:

Box 24 must always be completed even if there are no insurable earnings. Enter the total amount of insurable earnings you used to calculate the employee’s EI premiums that you reported in box 18, up to the maximum insurable earnings for the year. Reporting the correct EI insurable earnings in box 24 will reduce unnecessary pensionable and insurable earnings review (PIER) reports for EI deficiency calculations. [Source]

If you have an amount in box 16 or 17 (CPP or QPP premiums withheld), you must include an amount in box 26. Here are the CRA’s instructions for slip issuers:

Box 26 must always be completed even if there are no pensionable earnings. Enter the total amount of pensionable earnings paid to your employee, up to the maximum pensionable earnings for the year. Reporting the correct CPP pensionable earnings in box 26 will reduce unnecessary pensionable and insurable earnings review (PIER) reports for CPP deficiency calculations. [Source]

If you still have questions, please contact your slip issuer.