The change in how FICO is measured could make it more expensive for millions of Americans to borrow.
The gap between "high scores and low scores is likely to get bigger," says AnnaMaria Andriotis of the Wall Street Journal.
Nearly six in 10 Americans now have a FICO score at or above 700, which is considered "good" credit.
Experian says consumers who let the firm monitor their checking accounts could get easier access to credit.
It's something parents need to think about more and more these days.
The country is designing a credit score that factors in social behavior.
Once a closely held secret, free scores are abundant.