Activities The Great Outdoors Where Registration Numbers are Placed on a Boat Coast Guard regulations govern the placement of registration numbers Print Stephen Saks/Lonely Planet Images/Getty Images The Great Outdoors Sailing Gear Climbing Skiing Snowboarding Surfing Paddling Fishing Scuba Diving & Snorkeling By Ericka Watson Ericka Watson Ericka Watson is a certified U.S. Coast Guard coxswain and captain. As a Coast Guard officer, she led crews in search and rescue missions. Learn about our Editorial Process Updated on 02/21/19 The Coast Guard requires that all vessels must be registered with the state in which they'll be operated and that their registration numbers must be clearly displayed on the boat. When you've registered your boat with your state, you'll receive a registration certificate with the registration numbers. Where you place them on your boat is important. Think of them like license plates on cars. If they were permitted to be posted anywhere, no one would know where to look for them in an emergency. You can comply with Coast Guard regulations by following these simple steps. Register Your Boat Register your boat with the appropriate state licensing agency. You are required to do this and to affix the state sticker within six inches of the registration number. Format the Registration Numbers for Your Boat The Coast Guard requires that the letters be plain, block, and at least three inches high. They must be legible. They can be painted on, but purchasing vinyl letters from a marine supply store will provide a cleaner, neater look unless you're an expert artist. The numbers must read from left to right, as in the usual English sequence. This applies to both sides of the vessel. You aren't going for any mirror-reading. The color you choose for your numbers has to contrast against the color of the boat so they can be easily read. Don't try to camouflage the number s or you may run afoul of the authorities. Check with friends and relatives to ensure they're readable. Some people may be colorblind and unable to distinguish contrasts like red/green. If you ask several people to read your numbers and they can all do so correctly, you should be safe. Black on white or white on black is always good. Don't display any other numbers on either side of the bow—keep that area clear for only the registration number and the state sticker. Separate letters from the numbers with either a space or a hyphen—for example, ST-321-AB or ST 321 AB. The separation distance or hyphen must be the width of a letter other than 1 or a number other than 1. You don't want to place them too closely together. Be sure to leave enough space on either side of the registration number so you can add the state sticker. Some states require that the sticker must appear before the number while others want it to be placed after the number, so leave enough space on either side. The numbers have to be permanently attached, so you can't get away with using magnetic numbers or others that are easily removed or switched around. Where to Display Your Boat's Registration Numbers Display the numbers on the front portion of your boat. This means the forward half of the vessel. Find the midline of your boat and make sure you have the space allocated on the front half. Affix the state sticker within six inches of the registration number, either before or after it, depending on your state's rules. Check for more specific requirements in your state just to be on the safe side and you can be sure to get it right.