While every situation is different, credit card companies generally follow a similar path with attempting to collect on overdue accounts. Because lawsuits cost money for credit card companies, they usually don't sue for small balances. They also go through a lengthy collections process prior to filing a suit.
The first step from credit card companies usually involves correspondence and phone calls. As the account becomes more overdue, the phone calls and mailings might become more frequent or demanding. The language in such letters usually details how much is owed and discusses possible consequences if the consumer does not contact the credit card company to arrange payment. The letters might also provide some options for making payment plans.
At some point, the credit card company will close the account or reduce spending limits below what is owed. This is usually done to reduce the credit card company's liability.
Usually after six months of no payment on the account, credit card companies revert to outside collections agencies. This could be done by selling the debt to a collector or by working with a collector in a contract capacity. At this point, consumers may begin receiving threatening phone calls and letters from collection agencies. While collection agencies can be scary to deal with, there is a silver lining in some cases. Some collectors are able to work with consumers to settle debts for less than is currently owed.
Finally, if the debt remains unresolved, the credit card company may file a lawsuit. It's usually in the consumer's best interest to work with creditors prior to a lawsuit. If you are unable to pay debt and have a number of delinquent accounts, debt relief efforts such as bankruptcy might be a good option.
Source: CardHub, "Can a Credit Card Company Sue You?," John Kiernan, accessed July 24, 2015