Most US residents own a car — less than 10%
don't have access to one in their household. In America, car insurance typically covers rental cars.
Therefore, if you own a car and have full insurance, then your rental car will likely be covered under your policy. But be sure to check this before you go rent a car by either calling or emailing your insurance company.
In addition, credit cards (Visa, Mastercard, and American Express) typically also cover rental cars as secondary insurance. This means that any other insurance you have will be used first and the credit card will cover anything else. Credit cards only cover the rental car itself, though, and not any third-party damages.
Liability insurance is a different issue. Rental cars are required to carry the minimum insurance amount of each state, but in many states, this amount is very low. You, therefore, will likely want to purchase Supplementary Liability Insurance if you do not have your own car insurance.
Finally, if you do not own a car or have coverage through your credit card, you will have to purchase the rental company's CDW. While some of the larger companies may not check that you have insurance, you do not want to be liable for the entire value of the car. If you purchase the rental company's CDW, you won't be charged more than its deductible for any damage that it covers. Note
: If you only have liability insurance (the legal requirement in all states), then it will cover any damage you cause to other cars or injuries to others, but it will not cover the rental car itself. In this case, you will need to purchase the rental company's CDW.Another note
: Be careful if you plan to rent from smaller companies, particularly those in Florida. These companies often only accept certain insurance companies and will require you to purchase their CDW and/or Supplemental Liability Insurance if your insurance is through a different company. This can dramatically increase the price you'll have to pay.