Credit card rewards are the most polarizing frugality topic. Evangelists claim they fund free travel indefinitely. Critics point to the debt that cancels every benefit. Both are correct about different populations.

The only rule that matters: Pay the balance in full, every month, without exception. Credit card interest rates are 20–30% APR. No rewards program generates returns that survive carrying a balance. If you cannot commit to this rule, do not pursue rewards cards.