Closing credit cards you’ve paid off can lower your credit score. Closing a card causes your available credit to drop, reducing your borrowing power.
You can pay off other card balances to reduce the effect of closing the card on your credit utilization, which can influence your score.
Another way to increase your available credit is to ask your creditors to raise the limits on cards you already have. To be sure, raising the limits on your credit cards doesn’t mean you should go out and spend more. This is just a tactic to improve your credit score quickly.