An expense refers to a cost incurred in the business to generate revenue. The total expenses are netted off from revenue to arrive at the net profit. It includes, but not limited to, the following: an expense resulting in an outflow of cash i.e. cost of goods sold, marketing expense, rent, employees compensation (salary, bonus, CPF), utilities etc. a non-cash expense i.e. depreciation, amortisation, impairment, unrealised gains/losses etc.