Does it help improve my credit score to pay off my credit cards every month?

According to the Consumer Financial Protection Bureau (CFPB), not necessarily. It's more important to pay your bills on time, and don't use very much of your available credit.

There is a thing called a "credit utilization ratio" that measures how much of your available credit that you use. For example, if you have a $5000 credit limit on a credit card, and you charge $4500 each month, even if you pay it off each month, that will likely reduce your score somewhat, because you are close to being "maxed out" and it looks like you are in danger of default.

Credit experts stay that you should try to keep your utilization ration below 30%, it will likely help your credit score. So even if you have a low limit on a credit card, say $500, you can help your credit score by never having a balance on the card of more than $150.00.