Image: Credit card © Creatas, SuperStock

Staying in touch with your credit card companies prevents credit card fraud, stops criminal activity in its tracks and helps you avoid inconvenience in cases where there might be an appearance of fraud.

Here are seven instances when you should pick up the phone to call your credit card company:

1. New credit card arrival.

Use your home phone to call the activation number on the credit card when your new card arrives in the mail. This lets your credit card company know the card arrived safely at its destination.

2. Unauthorized credit card use.

You've never been to Texas, yet charges at Texas restaurants, gas stations and retail stores appear on your credit card statement. Call your credit card company right away if your statement includes purchases you didn't authorize. The issuer can then cancel the account number and issue a new card.

3. Lost or stolen credit card.

It's better to cancel the account and get a new card number than to wait for the errant card to turn up, even if you think you misplaced a credit card. If your card was stolen, call law enforcement and your credit card company immediately. Thieves can go on spending sprees quickly.

5. Change of address.

Planning to move? Contact your credit card company with your new address to prevent important financial information from landing in the wrong hands.

6. Big trips and large purchases.

Notify credit card companies if you will be traveling and using credit cards away from home or if you're planning unusually big purchases, such as furniture and appliances. Otherwise, your account might be flagged for potential fraudulent activity because of the unusual activity, and issuers in some cases might block use of the account until they can confirm that the charges are legitimate. Don't let that inconvenience get in your way.

7. Missing credit card statement.

Know when your credit card statement should arrive, and notify the company if it's late. Mail theft is among the tactics used to commit credit card fraud. Thieves steal your credit card statement and use the information to run up charges on your account.

This article was reported by Barbara Marquand for IndexCreditCards.