The % of how much of your credit card you are using is 30% of what determines your credit score. Credit Bureaus take into account how much of each card you are using, as well as how much of your total credit you are using. You want to keep both figures between 1-10% (20% is not a big deal).
Using 100% of your Chase Freedom card with $3000 limit and 0% of your Barclay World Arrival Card with a $3000 limit
Using 50% of each card. The total credit utilization is the same (50%), but the first situation has a higher individual credit utilization on the Chase Freedom. It is better to evenly distribute your credit utilization.
Credit Bureaus check your credit utilization once a month
Your 30-day statement cycle looks like this
Start Date March 05th
***Purchases are made***
30 days later...
Closing Date April 04th
***Credit issuer reports how much of your credit limit you used to the credit bureau around this day***
~3-4 week grace period...
Payment Due Date May 1st
Call your credit issuer to find out when they report your credit utilization to the credit bureaus. In my experience, Barclaycard reports 1 business day after the closing date.
Does This Information Benefit Me?
Most likely not. You can reduce your credit utilization by making early payments. Unless you are using a very high % of your credit limit every month (50%), the effect on your credit score will be insignificant and temporary. Also, by paying your debt before the grace period is over, you will miss out on a few cents of interest that this money would have collected in your savings account. This of course, is also insignificant.
If you pay your balance in full every month, use less than 20% of your credit limit, don't worry about credit utilization tricks. Any activity would be more meaningful than worrying about this.