Is non business income same as allowable expenses?

No, non-business income and allowable expenses are not the same. Non-business income refers to any income that is not generated from a business or trade, such as rental income, investment income, or wages from employment. Allowable expenses, on the other hand, are expenses that can be deducted from taxable income for the purpose of calculating taxes owed. These expenses are typically related to running a business or trade, such as office supplies, rent, utilities, and employee salaries.