(MONEY Magazine) – In the Fall of 1995, Jo Pettit, a writer from Amityville, N.Y., emptied out a safe-deposit box at her hometown bank, Columbia Federal Savings. The following January, the bank mailed her an annual bill for $40. Pettit scrawled "Cancel" across the notice and mailed it back. The next month, she received another bill. She canceled again. You guessed it: the next month, another notice--and another cancellation. Their correspondence has now been going on for 12 months without resolution. "Doesn't anybody open these letters?" wonders Pettit. (The bank declined our request for comment.)

As thousands of people like Pettit are discovering, canceling rentals, subscriptions or services that you no longer want can take longer than ending a marriage. According to consumer advocates, services most impervious to single-request extermination include online service providers; book, music and health clubs; lawn-care services; and, yes, even magazine subscriptions.

Of course, some long good-byes are simple foul-ups. But according to Robin Leonard, author of Money Troubles (Nolo, $19.95), the reality is: "It's cheaper to maintain a customer than to find a new one." Adds Frank Bruni, co-author of Consumer Terrorism (HarperPerennial, $12): "It's like a game of chicken, and 90% of the time it's the customer who blinks first"--and keeps on paying.

On the theory that life is too short to needlessly repeat yourself, here are five tips on how to cancel once and for all:

1. Stick it in their ear, then put it in writing. First, call the customer service number printed on your bill. To minimize the chances of getting a busy signal or being left on hold for hours, phone during off-peak times--generally early in the day and at the end of the week. (A speakerphone and a taste for bad music help ease the pain too.) Or, if there is a 24-hour service number, make your call after 11 p.m. When you get through, keep a record of the date and the name of the person to whom you delivered your verbal cancellation. Follow up with a certified letter to the customer service department.

2. Get your credit-card issuer on your side. If the unwanted service continues to be billed to your credit card, send a copy of the certified letter along with your credit-card number to your issuer within 60 days of the erroneous charge. The card company can put additional pressure on the merchant.

3. Press the up button. Also write directly to the company's president. Restate your previous efforts and ask for his or her intervention on your behalf. Mention that your time--and the company's--would be more profitably spent on other matters. Add that you'd hate to have to spread the word to your friends and to the media about the company's poor service. Herschel Elkins, a California assistant attorney general, suggests that you close with a "cc: state attorney general": "It lets them know you're serious and often gets quick results."

4. Complain to the Better Business Bureau. The nation's 137 BBBs collect and disseminate complaints and can mediate disputes between you and the merchant. Call the BBB in the state where the company is located. Just the threat of tattling is sometimes enough to scare an offending company into action.

5. Write directly to your state attorney general to request that office's intervention. Attorneys general typically write back within a few weeks. They may make contact with the company directly or in severe cases bring action against the company.

Still no response? As long as you've documented your attempts at cancellation, and assuming that no fees are being charged to your credit card, simply ignore the continuing bills. As author Leonard said when her lawn was mowed by a gardener a month after she'd canceled his contract, "Thanks for the free cut."

--Joan Caplin