The ticketing state of Montana and your home state of California are both members of the Driver's License Compact (DLC) so if you are convicted of a speeding offense in Montana their courts will notify the CA Department of Motor Vehicles.

DLC member states vary on if they place out of state citations for moving violations (after you have received a conviction for the offense) on your driving record or not. California has elected to add out of state violations to your motor vehicle record (MVR) and place points as if the offense occurred in state as well.So for speeding this is normally 1 point on your CA MVR.

Since the MT citation will go on your CA driving record your insurance carrier could see it and thus the speeding violation could affect your rates.If would depend upon your specific insurance company's rating system if this one infraction would raise your rates or not.

If Montana offers deferred adjudication, traffic school or another type of option where you would not be convicted of the speeding ticket than you may want to see if you are eligible to participate since if you are not convicted of the traffic offense then it would not be reported to California.