If, for example, the person you add to your policy is a child, then your rate is all but guaranteed to go up because drivers under 25 are perceived to be very risky to insure. They’re also penalized for their lack of driving experience.
If the person you add to your policy is a spouse, then your rate may drop. Married couples tend to get discounts because they’re assumed to be more responsible and less likely to drive recklessly.
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