If I buy a privately owned vehicle how long do I have to get insurance?

You should get car insurance quotes and purchase a policy before you drive the car if you do not have coverage at all. If you have car insurance for another vehicle, then your existing policy will temporarily cover the car you buy. But don't wait too long to inform your insurance company.

In most cases you have 14 to 30 days to let your car insurance company know you bought a new vehicle. If you forget to inform the insurer and the grace period lapses, the car will be uninsured.

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Rules vary among insurers, so check with your insurance company about coverage and the length of the grace period before you buy a car. Progressive Insurance and Allstate have 30-day grace periods, for instance, while State Farm has a 14-day grace period--except in states that require longer grace periods.

Keep in mind that if you dropped collision and comprehensive and carry only liability on your old car, until you tell the insurance company about the change, that's all the coverage that will apply to the new car during the grace period.

Collision pays for repairs of your vehicle if it's damaged in an accident, and comprehensive covers damage from causes other than traffic accidents, such as hail, flood, theft, vandalism and collision with an animal.

Both collision and comprehensive auto insurance are optional types of coverage, but they're highly recommended for new or used vehicles that still retain much of their value.

For more, see auto(matic) coverage for new cars.