What Counts as a Purchase for Rewards?
Purchases earn; cash-like transactions do not
A purchase is you paying a merchant for goods or services, and that is what earns rewards. Cash advances, ATM withdrawals, balance transfers, and buying cash equivalents like money orders are treated as accessing cash, not spending, so they earn nothing and often add fees and immediate interest. The details are in do balance transfers and cash advances earn rewards.
The gray areas
Some transactions live in between. Gift cards usually earn rewards and can even hit a bonus category, covered in buying gift cards for rewards, but reloadable and prepaid cards can code as cash equivalents. Fees, interest charges, and the annual fee itself never earn rewards. Rent and taxes may or may not earn, depending on the processor and any fee involved.
Why it matters for your estimate
If you assume rewards on cash advances or fee payments, your projected earnings will be too high. A good rewards calculator only counts real purchase spending for exactly this reason, so the ranking reflects what you would actually earn. When you estimate rewards, include only the spending that genuinely counts as a purchase.