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Depending on the type of payroll category (earning, deduction, tax, benefit), there are different boxes that can be assigned. Make sure you're selecting the correct one! Then, if the tax form box you're looking for isn't listed, it's most likely in the sub-box for the T4. Simply tick the 'OTHER' box for the T4 and in the sub-box column, select the correct box! 

Are there separate boxes for CPP2 or QPP2? 

As of January 2025, there are separate boxes for CPP2 (16A) and QPP2 (17A). 

II. Creating T4s, T4As, and RL-1s 

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