Congress is throwing a rope to credit card users who have been trapped by an industry whose standard operating procedures include deceptive practices, arbitrary rules changes and crippling interest rates. The aid couldn't come at a better time.

The number of overdue loans continues to increase, and with default rates rising, credit card issuers have been summarily raising the interest rates charged borrowers who've never lost their job or missed a payment. People with low interest rates have seen them double.

Congress just passed a credit card reform bill that adds to the reforms recently imposed by the Federal Reserve Board. President Obama signed the bill on Friday, and its provisions will be effective within nine months. But more work remains to be done to ensure that consumers get a fair shake.

Credit card issuers make most of their money by charging merchants who accept the cards a small percentage - usually between 1 and 2 percent - of the value of the transaction. That means sellers make less money when people pay with the cards. Yet the bill, for example, does not allow merchants to offer a discount to customers who pay with cash, check or debit card. That should be remedied. People who make a purchase with their own money rather than someone else's shouldn't be penalized.

The bill restricts or forbids some of the industry's most unfair practices, including the ability to charge a penalty interest rate after a late payment on a previous month's balance that had already been reduced or paid off.

Here are some of the other changes it will make:

• Bills will have to be sent a minimum of 21 days before a payment is due. Any payment received before 5 p.m. on a business day must be credited. No same-day early deadlines.

• A penalty interest rate, in most cases, may not be imposed on a balance until a minimum payment is at least 60 days late. According to the Pew Charitable Trust, 82 percent of credit cards permit unlimited penalty rate increases.

• Card companies will have to give borrowers at least 45 days' notice before raising interest rates. Similar notice will have to be given to changes in the terms of the card and rewards programs.

• When a borrower has loans at different interest rates, the lender must apply payments to the loan with the highest interest rate, not, as often happens, to the loan with the lowest rate.

• The instantaneous approval of exceeding a credit limit will not require the borrower's approval. No more $39 fee when a $10 purchase puts a borrower over the limit.

• People under age 21 will either have to show proof of their income or get a parent, spouse or legal guardian to be a co-signer.

• The terms and conditions of loans will have to be spelled out clearly - no more gibberish in mouse print.

There will be a price to pay for these protections. Interest rates are likely to rise, and people who are poor credit risks will find it harder to get a card.

Responsible credit card users who pay off their balances and those who use plastic to pay for everything to rack up airline miles could also see changes. Issuers may cap reward programs or charge annual card fees.

Such tradeoffs are worth it. Credit cards are wonderful tools, but they are tools that were being abused on both ends, by borrowers who failed to use them responsibly, and by lenders whose practices became rapacious.