How DMV Points Transfer Between States
If you get hit with a violation while away from your home state, you can expect it to follow you home nine times out of ten. And if you move between states while you're carrying points on your license, they'll usually transfer over according to the terms of the Interstate Compact Act.
Interstate Compacts And Changing Residency
Most of the states have opted in to a set of compacts that requires them to share DMV information. When you change your residency from one member state to another, your points will follow you if the new state has a points system.
You may not end up with an identical amount of points, however. The points will be re-assessed according to your new state's rules, based on what they assess for the violation that you committed in the old state.
How States Share Violation Information
Each set of states has to have a formal agreement in place stipulating that they'll voluntarily submit information about traffic violations and convictions to each other. Prior to the 1960s, that meant that motorists could sometimes get away with ducking out of a ticket or court appearance if they were pulled over while outside of their state of residence, as not all of the states had clear agreements in place with each other.
That situation began to change in 1960, when the Driver License Compact was created. This is a set of laws that states can opt into, ensuring that information about traffic violations would be shared between them. By the 1990s, the vast majority of the states had opted in. As of 2016, only five states have held out of the Driver License Compact: Massachusetts, Michigan, Wisconsin, Georgia, and Tennessee. States that have opted in are required to assess their native penalty for out-of-state violations if they have an equivalent law on the books. This means that if you get a speeding ticket in another state, you'll be assessed for the amount of points that a similar speeding offense would get you in your home state -- not the amount that the state you were visiting requires.
The Driver License Compact is not the only agreement between the states, however. It has also largely been paired with the Non-Resident Violator Compact. This agreement stipulates that if you are cited in a member state other than your own and don't pay your ticket, your home state is allowed to suspend your license. There are certain offenses that this agreement does not apply to, however. Parking violations, exceeding weight limits and registration issues are not included. These will remain on the books in the state you are cited in, but will not be passed on to your home state. Most states are currently members of this compact, but there are a few holdouts, and in most cases they differ from the states that have opted out of the Driver License Compact: Alaska, California, Montana, Oregon and Washington. Michigan and Wisconsin have opted out of both the Driver License Compact and the Non-Resident Violator Compact.
A new compact called the Driver License Agreement has been proposed to unify and revise the terms of these two agreements. This compact would expand the terms of the Non-Resident Violator Compact to include things like parking and registration offenses. Thus far, however, adoption of this compact has been very slow. At present only Arkansas, Connecticut and Massachusetts have adopted it.
So what if you live in a state that doesn't have one of these compacts? Or Michigan and Wisconsin, which subscribe to none of them? You're still not entirely out of hot water. These compacts only mandate that member states report violations to each other. States will very often report violations of this nature to each other as a courtesy even if they aren't required to. If that happens, even if your state doesn't have a formal agreement in place with the reporting state, they may still assess you points.
States Without Point Systems
There are nine states that don't have any sort of point system, but nearly all of them are members of the compacts described above.
If you're moving from a state without a point system to a state that has one, the new state will usually look at your previous violations and assess points based on their own internal rules.