The cost of credit fraud is $3 billion a year and growing. Even if you are not personally a victim, everyone pays for credit card fraud in higher finance charges and membership fees.

Actual theft of cards is only one form of credit card fraud among many including:

Thieves who pick discarded receipts or carbons out of trash cans to get the card numbers.

Dishonest clerks who make extra imprints of cards for personal use or to sell.

Calls (or letters asking you to call) announcing that you have won (or been selected in a “marketing program” for) a free or unbelievably low-priced travel package, but, your credit card number is required for “identification purposes only.”

To protect yourself against credit card fraud, do the following: Sign new cards as soon as they arrive. Carry your card separately from your wallet. Keep a record of your card numbers, their expiration dates and the phone number and address of each issuing company in a secure place. Keep your card in view after you give it to a clerk. Get it back promptly after they the clerk has imprinted it. Avoid signing a blank receipt. Draw a line through blank spaces above the total when you sign. Destroy all carbons and voided (when a mistake has been made) receipts. If a clerk has to keep a voided receipt for the store’s accounting system, be sure to get a copy. Save all credit card receipts, open your monthly bills promptly and check your receipts and payments against the statement. Immediately report in writing any questionable charges to the card issuer (some have a form on the statement for this purpose). Notify card companies in advance of a change of address.

To protect yourself against credit card fraud, don’t: Ever lend credit cards to anyone. Leave cards, receipts or carbons where anyone can pick them up. Put a card number on a postcard or on the outside of an envelope. Give your card number over the phone unless you are dealing with a company you are sure is legitimate. If you aren’t certain about a company that calls you or whether the caller actually represents the company he or she claims to, check with Northeast COMBAT before giving them your credit card number for an order. If the call is honest, they’ll be happy to have you call back or call you again.

If your card is lost or stolen, call the issuers immediately. Most have a toll-free number for reporting missing cards; some provide 24-hour service. The maximum amount you can be held accountable for is $50 per card under federal law.

Consumer Forum is a collaborative effort of the Bangor Daily News and Northeast COMBAT. Send your questions to Consumer Forum, Bangor Daily News, P.O. Box 1329, Bangor 04402-1329. COMBAT is a membership organization with basic dues of $10 a year. For membership information write to the above address. Please enclose a large, stamped, self-addressed envelope.