Can I put my girlfriend on my insurance if we aren’t married?

With most insurers, unmarried couples can share a joint car insurance policy or add each other as listed drivers to separate policies. There can be pros and cons to sharing a policy, so check with your insurer to see if shared or separate coverage is best for you.

https://www.progressive.com/answers/car-insurance-for-unmarried-couples/#:~:text=With%20most%20insurers%2C%20unmarried%20couples,coverage%20is%20best%20for%20you.