Canada Tax Questions Answered by Experts
It is true that an amount paid as one lump-sum will generally not be considered a support payment because it is not paid on a periodic basis.
Sometimes a lump sum amount that is paid to bring a payer out of arrears is allowed for deduction.
Generally a prepayment is not support. A lump-sum payment made in place of several periodic payments that were imposed under a court order or written agreement, but were not yet due to be paid is a prepayment.
A payment that releases the payer from any obligation to pay arrears, future maintenance, or both is not support.
Spousal support is a deduction but the definition of what is support is crucial.