According to a representative of the South Carolina Department of Insurance, there is no grace period by law. He stated that an auto insurance company may by their own guidelines give a grace period (if no claims are placed during this period) but it varies from company to company.
Generally speaking, with many insurance carriers give you 30 days to get your new car registered and your title squared away and for you to inform them about your new vehicle. Some companies only offer this "grace period" for you to have coverage on your new car under your existing policy for only 14 days and some do not give you any grace period to place your car on your policy.
If your car insurance company does cover you for period of time after you have purchase a car but before you have technically placed the car on your policy then normally you must be replacing a car already on the policy (say you traded in a car and replaced that car on your policy with the new car) and the coverages extended to you will be the same as the car you are taking off the policy.
Since insurance companies' policy guidelines vary in South Carolina if a new car will have any grace period to be placed on your policy it is best to discuss this issue with your insurance carrier. Even if there is a "grace period" it is always best to inform your insurance agent when you have purchased a new car and to give him or her the information needed to get the motor vehicle properly placed on the policy as soon as possible after your purchase of it.
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