Gross income is usually defined as all of the amounts you received prior to any deductions or credits. For people that are self-employed, the Canada Revenue Agency considers that all amounts from a profession, business, commission, farming or fishing are included in your gross income.
Business income is a broad term and includes income from any activity you carry out for profit or with reasonable expectation of profit.
Some amounts do not need to be included in your gross income. For business owners, this can include any GST/HST credits, most gifts and inheritances, lottery winnings and most amounts received from a life insurance policy following an individual’s death.