Hi, welcome to the forums!
The util that you see on your myFICO score reports is your total util: sum of balances reported divided by sum of credit limits (not available credit, but the total credit limits.) The total util seems to be the more important figure. But the scoring formula also looks at individual util, so you don't want to let one card get really high.
One thing that you can do to avoid this is to pay your balance down or off several days before the statement is due to drop. Most lenders report the balance that is on the statement. In this way, you can control the amount of debt reported, lowering your util and raising your scores.
We used to say that this was mostly useful if you were getting ready to apply for something and wanted to optimize your scores. In these days, with banks seemingly looking for any reason to panic, it seems to help to have the lower balances reporting. If you have an HSBC/Orchard bank card (not store card) or US Bank, they seem to report the balance on your account as of the last business day of the month, not the balance that displays on your statements. Some local lenders do the same. If you have one of those, you might want to time your payments accordingly.
You should use both cards through the month, if only to keep the lenders from closing them for inactivity. Even a large Slurpee will keep it alive, although they might not want to keep you at your current credit limit if that's all they see.
If you haven't already, please read
Understanding Your FICO ® Score and
Credit Scoring 101 (at least the first post.)
These will give you the background knowledge you need to understand what you read here on the forums.
* Credit is a wonderful servant, but a terrible master. * Who's the boss --you or your credit?
FICO's: EQ 781 - TU 793 - EX 779 (from PSECU) - Done credit hunting; having fun with credit gardening. - EQ 590 on 5/14/2007
