How many points will your credit score increase if pay down credit cards?

Depends on lots of things, especially what percent usage you have now, and what you bring it down to. Unfortunately it might not happen immediately, but over time. Usage means the current balance divided by the max limit. Lenders like to see you using less than 30% of your total maximum limit. Then again, it's good to pay down credit cards for other reasons than just to improve credit score. Lower balances means less money going to interest. That's extra money in your pocket.