Dedicated users of rewards credit cards can easily rack up hundreds or even thousands of dollars a year in cash back, points or miles. Are those rewards taxable? Usually, no.
Discounts, not income
In general, the IRS views credit card rewards as a discount rather than as income. So if you’re getting 2% cash back on a $100 purchase, that would be considered a $2 discount. Discounts aren’t taxable, so you don’t need to keep track of your credit card rewards for tax time.
Business purchases are different
Although rewards on personal credit cards generally aren't taxed, different tax rules apply with business credit cards. Generally, business expenses are deductible against business income. If you spend $500 on something for your business, you can deduct $500 on your business taxes.
But credit card rewards reduce the amount of that deduction. If you earned $10 in rewards on that $500 purchase, then that purchase really cost your business only $490 — and that's all you can deduct. In this case, the $10 isn't considered income, but since it reduces the deduction by $10, it has the same tax effect.
And here's a wrinkle within the wrinkle: If you’re use a personal credit card to make a business-related purchase and then you get reimbursed by your employer, any rewards you earn won't be considered income by the IRS.