Liz Weston

Dear Liz: I know there are different factors involved, but I find a recent upsurge in my FICO score inexplicable. My score went from about 740 to 815, according to a note in my most recent credit card statement. Yet I’ve done virtually nothing in the way of major credit activity — no purchases, no change in my already-low credit card use. I transferred about $800 from one card to another, and that’s it. If such small matters can affect the FICO score, it makes that score seem ridiculous. Can you offer any possible explanations?

Answer: Credit scoring formulas are a bit of a black box, but they are sensitive to how much of your available credit you’re using.

If you transferred the balance from a card with a very low credit limit to one with a higher limit, your scores typically would improve — although perhaps not as dramatically as the increase you’re describing.

Your scores might also improve if your balances dropped on other accounts or something that was negatively impacting your credit “fell off” or stopped being reported. The simple passage of time can improve your scores, as well, increasing the age of your credit accounts and the time since your last application for credit.

It’s impossible to say exactly what combination of factors may have affected the score you saw, but at least it moved in the right direction.