1. Visit the County Auditor's Office
The Auditor's office will find out how much tax you owe on your car for the State of South Carolina. The tax will vary based on the make, model, and year of your car. I have a 2013 Toyota Corolla and it cost $375 in taxes- Ouch- so that might help put it in perspective for you. You will need your registration and license when you go to the Auditor's office.
Hint: I heard people saying that South Carolina had a $300 cap on taxes for vehicles, but that is only on the sales tax. You will be paying a property tax and that, unfortunately, does not have a limit.
This in the same building as the Auditor's office and is just across the hall. Here is where you take the slip from the Auditor's office and pay your tax. They accept Mastercard and Visa, Checks, or Cash
3. Transfer Your Registration and Tags
For step 3 you need to visit the Williamsburg County DMV. There is rarely much of a wait here, but don't visit between 11:30-1:30 if you can help it. Most of the staff are out to lunch during this time and the lines get longer. They will charge you $24 to transfer your Registration to South Carolina and $15 for a new tag. I already had my South Carolina License at the time, but if you do not yet have one you will need to do this at the same time ($15).
* See my post on the DMV for tips and information
Paperwork needed for Registration:
2. Previous Registration
3. Title (If own your car)
4. Lein Holder's Information (If you are making payments)
Paperwork needed for License:
1. Former License
2. Proof of Residency (Water bill, power bill, copy of lease, etc.)
3. Proof of Citizenship (Passport or Birth Certificate- no copies allowed)
4. Proof of Social Security Number (SS Card or Pay roll stub are usually the most accessible)
5. Proof of Insurance (Insurance Card- and the Geico Commercial is wrong... they will not accept an online card...)
* For full list of possible options for each category, look here.
Unlike most states, South Carolina DMVs (at the least the Williamsburg county one) will not send your tags back to your home state for you. I suggest calling your local DMV back home for information on what you need to do. Alabama wants a copy of my new registration and my old one with my new address on it. They said I can mail it in to them but I am going to take it up to the office when I am back home this summer.
This is hopefully true for every state, but you may get a refund on some of your taxes if you didn't spend a whole year in your previous state. Ex. You paid New Hampshire taxes in April that are suppose to last 12 months. If you pay new taxes to South Carolina in June, you should get 8 or 9 months worth of New Hampshire taxes back because you didn't use them.
For additional information and prices on Motorcycles or other types of vehicles, look here.
Good luck and let me know if you have any questions!