How to use the right credit card for each purchase
Cards pay different rewards in different categories. A four-step way to find which card in your wallet wins at the grocery store, the restaurant and the gas station, and how much the wrong card costs you.
Updated October 31, 2026
Why it matters
Most rewards cards pay more in a few categories and less on everything else. Paying for dinner with a card that pays its lowest rate there, when another card in your wallet pays several times more, leaves money behind every month.
1. List the cards you already hold
Write down each card and what it pays for groceries, dining, gas, travel and everything else. Note any cap: many cards pay the higher rate only up to a set amount of spending each month or year.
2. Check where each card is accepted
Not every store takes every card network. A card that pays well but isn’t accepted at your grocery store earns nothing there, so the winner is the best card the store takes.
3. Value points honestly
Points are worth what you redeem them for. A point valued for travel may be worth less as a statement credit, so use the value you actually get, and treat any estimate as an estimate.
4. Look back three months
Sort your card purchases by category. For each category, compare what you earned with what your best accepted card would have earned. The difference is what the wrong card cost you, and it tells you which card to reach for next time.
In habitt
habitt’s card check does this for you with the cards you link: it sorts three months of purchases, finds the best card you already hold for each category, and shows the difference. Purchases it can’t match to a card or a category are counted as unchecked, never guessed.
General information to help you think it through, not financial or tax advice.