Effective Valentine's Day — Saturday — you will no longer be able to get your FICO credit score from Experian, one of the three major credit bureaus.

The company notified Fair Isaac Corp., the firm that created the credit-scoring model most used by lenders, that it is terminating its relationship with www.myFICO.com, a Web site that sold FICO credit scores and other information directly to consumers.

This means generally that Experian customers will not be able to see the FICO scores lenders are using in determining their credit levels.

Although there are a number of credit-scoring models available, it's the Fair Isaac system that is most used by lenders to make millions of credit decisions each year. According to data from Fair Isaac, more than 90 of the 100 largest financial institutions use FICO scores. The 25 largest card issuers use it, as do the 25 largest auto lenders.

Credit-scoring models apply a mathematical formula to a consumer's credit history. For the most part they all use the same range of factors — most importantly, late payments and the amount of debt owed — to produce a three-digit score that is supposed to represent a person's likelihood of repaying debt.

This issue isn't about which scoring model is better. It comes down to consumers having access to what most lenders are using to grade them — and that is usually a FICO score.

"Experian's Valentine's Day present to 200 million American adults is to make sure they have no access at all to any Experian-based credit score that is widely used by lenders," said Craig Watts, public relations director for Fair Isaac. "Goodbye, transparency."

Consumers will still be able to obtain FICO scores based on data from their files at Equifax or TransUnion, the two other major credit bureaus.

The squabble between Experian and Fair Isaac follows a lawsuit Fair Isaac filed in 2006 against Experian, Equifax and TransUnion after the three developed a competing model called VantageScore, which uses a different scale.

VantageScore's scale ranges from a low of 501 to a high of 990. The FICO score runs from a low of 300 to a high of 850.

Fair Isaac has since dropped Equifax from the lawsuit.

The suit is still ongoing, alleging that the VantageScore joint venture creates unfair competition and violates antitrust laws.

So where does this all leave Experian customers?

You may still be able to get a look at your Experian FICO score by simply asking your lender. In some mortgage transactions, you are entitled to the credit score without charge.

You can also complain to the company.

And you can complain to Congress, which has it in its power to force transparency and make the most widely used credit-scoring system available to the public for free.

Congress has stepped in before. It amended the Fair Credit Reporting Act to open up the credit monitoring process by forcing each bureau to provide all customers with a free credit report once every 12 months. (You can get your reports by calling 877-322-8228 or at www.annualcreditreport.com.)

Here's how I see this FICO fracas: If the market has widely embraced the FICO credit score, Congress shouldn't allow business quarrels — not now, when credit is hard to get — to result in shutting down access to information that is essential to obtaining the best loan, insurance rate or even a job.