Decline the insurance on a car rental? Know terms are changing.

For years, the recommendation on rental car insurance was to use coverage from a credit card or your personal auto policy and to decline the coverage offered by the rental agencies. But like so many other things, Consumer Reports says, that's changing!

Whether it's vacation, business travel or your car is in the shop, there are plenty of reasons to need a rental.

Before you consider the insurance add-on option, check with your personal auto insurance and the credit card you will use to pay.

Consumer Reports warns that some credit card contracts have changed terms. Recently, Discover stopped offering rental insurance altogether. American Express, Chase and Citibank still do, but check their terms and limits. If a credit card is your primary coverage, there could be a benefit to using it.

"Should there be a claim, the credit card insurance could be in line to cover it, and your own auto insurance rates may not change," said Octavio Blanco, Consumer Reports money editor.

To be covered through your credit card, you need to pay for the entire rental with that card and decline the rental agency’s coverage.

Blanco sayd, “However, if you are going to depend on your own auto insurance policy remember the rental will be covered under the same terms as your own car. So check those terms carefully.”

If your personal policy doesn’t have collision coverage, you might want to consider adding the rental car company’s. That can run as much as $30 a day. Liability can run $10 to $15 a day.

But if you're in an accident, you don't want to get stuck without the coverage you need, so those added costs could be worth it.

For those who travel and rent a car outside the U.S., personal insurance might not offer coverage. In that case, your best option may be to get the rental company’s insurance. It's always a good idea to read the terms carefully.