Originally Posted by
serpens
Are balances reported only at the statement date?
Generally yes.
Originally Posted by
serpens
When does the balance on a particular card divided by the credit limit on that particular card have an effect? Is it worth (or even effective) paying in advance of the statement date to reduce this ratio?
Yes to the latter, if your utilization drops from say 50% to 5%. As for the former, there is utilization for each card and there’s overall utilization; you can have a reasonable overall utilization, yet a card that’s maxed out.