A stolen credit card can be a major headache, for both you and your credit card company. Stolen cards cost financial companies billions of dollars each year, so they have a major interest in preventing fraud. As part of their anti-fraud measures to block unauthorized transactions, credit card companies can flag accounts that exhibit suspicious activity.

Location of Charges

Credit card companies pay attention to where charges are made and may flag your account if the locations of charges on your account are out of the ordinary. For instance, if you start shopping at stores you've never shopped at before or in a neighborhood you rarely visit, your card could be flagged. Using a card while moving, driving across the country or traveling internationally can also get your account flagged.

Uncharacteristic Spending

Your credit card company has records of your spending, so charges that don't fit your normal spending habits are suspicious and can lead to a flagged account. For instance, if you normally use your card to make minor purchases like paying for gas and you suddenly charge a $1,000 television, your credit card company might be suspicious of fraud. Similarly, if you rarely use your credit card, but decide to go on a shopping spree, your credit card company might suspect foul play and flag your account.

Charging Patterns

Suspicious charging patterns on your credit card can get your account flagged. When thieves steal credit cards, they often start out by making small charges to test whether the account is working. As a result, several charges made in quick succession or a series of small charges followed by large ones can get a card flagged.

Considerations

Losing a credit card or having a card number stolen is especially likely if you use a credit card while traveling. Consequently, credit card companies tend to be very suspicious of transactions made in foreign countries. If you plan to travel, it is a good idea to tell your credit card company where you are going and the dates you plan to travel ahead of time to reduce the chances of having your account flagged.