As per the Canada Revenue Agency (CRA) Box 20 includes any benefits shown in boxes 14, 15, 16, 17, 18 and 19. Do not add the amounts from those boxes to your income on your return. It also includes any recovery of Canada Pension Plan overpayments or payments for arrears.
The amount in box 20 may be correct. If you still need clarification please contact the issuer of the information slip.
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