Many people routinely decline the optional car rental insurance offered on-site when picking up the car. Besides the fact that nothing bad will ever happen to you or the car (*wink*), and the other fact that it costs money, why does everyone decline this coverage? Because many people know that most credit cards come with some sort of travel and/or car rental insurance. But which cards offer the best protection? It varies widely.

Coverage

Visa and American Express coverage is automatic, but Discover card and MasterCard holders aren't protected unless you have one of their elite-level cards (such as some airline-branded cards that have an annual fee). American Express also offers an upgraded coverage plan at $19/rental. Diner's Club cards have the best coverage, with automatic Primary coverage (you go through the card company first, not your insurance company as with the other cards). This automatic coverage is applied when you pay for the full value of the rental on the appropriate card (and decline any insurance provided by the car rental company).

Exclusions

Even if you have automatic coverage you still have to watch out for exclusions and time-limits. For example, Visa cardholders are protected, but only up to fifteen consecutive days of rental in your home country (31 days in a foreign country).Your coverage is also limited to automobiles not included in the following categories: expensive, exotic, and antique automobiles; certain vans; vehicles that have an open cargo bed; trucks; motorcycles, mopeds, and motorbikes; limousines; and recreational vehicles. Oh, and they don't include the countries of Australia, Ireland, Israel, Italy, Jamaica and New Zealand. But hey, other than that you're protected!

Lessons

Always read up on your card's benefits (usually available somewhere on the card's web site). Remember that most cards only provide you with secondary coverage—you need to deal with your insurance company first, and then the card company will cover any extras not covered by the insurance. So look into what type of coverage your current auto insurance provider provides you. Also, be sure to check on the deductible that you need to pay before any coverage kicks in.

For a full chart of what cards provide what benefits visit CreditCards.com.