THE JOYS OF SHODDY SERVICE. The major credit card companies are not making many friends, either among their cardholders or in Congress.

Americans use credit cards to pay for everything from groceries to speeding tickets. But they're increasingly besieged by colossal fees and interest-rate increases that seem to hit them without warning or justification.

Now, though, banks are under scrutiny from the Democrat-led Congress, which held hearings on credit card practices last week. Banks also are feeling competitive pressure to become more consumer friendly.

One practice, known as "universal default," is of particular interest.

Ever wonder why your card's interest rate spiked, even though you've always paid on time? The most likely reason is a practice known as universal default. That occurs when card issuers raise rates for those who made a late payment to some other company. Issuers may also raise your rate if your overall debt has increased. Nearly 45% of banks used universal default in 2005, according to Consumer Action, an advocacy group.

Credit card issuers defend this practice.

They argue that borrowers who are having trouble with other debts are more likely to fall behind on their credit card bills. But many consumers say the practice is grossly unfair.

The practice is of particular interest in that without the central clearing houses known as credit bureaus, a creditor only knows which of its own customers are slow to pay or nonpayers. The credit bureaus provide a potential efficiency-enhancing function in enabling any lender to discover which borrowers have bad histories elsewhere (it's more objective than asking your current squeeze's former boyfriend). At the same time, the credit bureau can serve as a facilitating practice for collusion (as .pdf; the shared information relaxes the "incentive compatibility constraint for collusion, in the absence of an explicit agreement among creditors to raise rates in response to the same evidence.) Thus there is a public policy tradeoff: is the public interest better served by expediting the discovery of delinquent and deadbeat borrowers or by making rational cooperation in an already cartelized industry more difficult?

The article also suggests that cardholders make use of the customer service department at the credit card company.

If you've been hit with a high fee because your payment was a day late, call your card issuer and ask for a reprieve. If you've been a solid customer, there's a good chance the issuer will waive the fee, says Linda Sherry, director for Consumer Action.

Getting your interest rate reduced is harder, [Card Rating's Curtis] Arnold says, but not impossible. Even if your bank won't give you your old rate, it might agree to reduce the new rate by a few percentage points, he says. A report by the Massachusetts Public Interest Research Group found that more than half of customers who complained to their card issuer about their interest rate succeeded in having the rate reduced.

Yes, call, but expect to be frustrated. I had a small error to straighten out, and rather than write a letter, I rang the customer service line. The problem was cleared up. In fifteen minutes. After I had spent two minutes working through the "enter this information" nonsense to get in. After I had spent three minutes dealing with an agent who was unable to solve my problem and unwilling to transfer me to a supervisor without requesting irrelevant information. After I spent another five minutes getting the supervisor to concede that the agent was in error. After that supervisor asked me to confirm my mailing address (IT'S ON THE STATEMENT. I RECEIVED THE STATEMENT. ARE YOU TELLING ME THE REST OF YOUR RECORD KEEPING IS AS BAD AS YOUR TRANSACTION POSTING?)

I will be forwarding a complaint about the "customer service" functions at credit card companies to the House Committee on Financial Services, should Members be interested in pursuing further abusive practices. I will also report the facts to the Comptroller of the Currency, with the request that the complaint be held for a reasonable time in their files, should the Committee expand its inquiry.