California boat registration is handled by the Department of Motor Vehicles, not a separate marine agency, and the process depends on whether your boat has a motor and how powerful it is

California requires registration for almost every boat used on state waters, whether it is a sailboat, motorboat, jet ski, or kayak with a motor. The Department of Motor Vehicles (DMV) issues boat registrations, and you will deal with them the same way you would for a car — though the rules about what needs registering and what documents you need are different. A boat without any motor does not need registration. A boat with a motor of any size does, unless it is a documented vessel (registered with the U.S. Coast Guard instead, which is rare for small recreational boats).

The registration itself is a certificate you keep on board, valid for one or two years depending on the vessel type. It costs money upfront and renews annually or biennially. Where you register depends on where you keep the boat: if it is moored or stored in a particular county, you register it there. If you move it to a different county, you need to update your registration.

Key Takeaways

  • California requires registration for any boat with a motor, regardless of size, unless it is documented with the U.S. Coast Guard.
  • You register through the DMV in the county where the boat is kept or moored, not through a statewide office.
  • You will need proof of ownership (bill of sale or title), proof of California residency, and identification to register.
  • Registration fees vary by boat length and motor type, and you pay them when you first register and again when you renew.
  • A valid registration certificate must be on board whenever the boat is in use on California waters.

What boats need to be registered in California

Any vessel with a motor — inboard, outboard, or jet drive — must be registered. This includes motorboats, sailboats with auxiliary motors, personal watercraft (jet skis), and even canoes or kayaks with electric motors. The size of the motor does not matter; even a small trolling motor on a fishing boat triggers the registration requirement.

Boats without motors do not need registration. This means a rowboat, canoe, sailboat with no motor, or paddleboard is not registered. If you later add a motor to an unregistered boat, you must register it before using it on California waters.

If your boat is documented with the U.S. Coast Guard — which is uncommon for recreational boats under 5 net tons — you do not register it with California. Coast Guard documentation is a federal process and takes the place of state registration. Most recreational boat owners register with California instead.

Documents you need to register a boat

Bring or submit proof of ownership. If you bought the boat from a dealer or private seller, you will have a bill of sale. If the boat was previously registered in California, you may have a title document. If you inherited the boat or received it as a gift, bring a bill of sale signed by the previous owner or a gift letter with their signature. The DMV will not register a boat without proof that you own it.

You also need proof of California residency — a driver's license, state ID, utility bill, or lease agreement showing your current address. If you are registering the boat in someone else's name (a business, for example), bring documentation showing that person or entity's residency or business address in California.

Bring a valid photo ID. If you are registering in person at a DMV office, your driver's license or state ID works. If you are registering by mail, a copy of your ID is acceptable.

You will also need the boat's hull identification number (HIN). This is a 12-character code stamped or attached to the hull, usually on the starboard (right) side near the stern. If the boat is very old or does not have a HIN, the DMV can issue one during registration.

How to register your boat with the California DMV

You can register in person at any DMV office in the county where the boat is kept, or by mail. In-person registration is faster — usually completed the same day — and you walk out with your registration certificate. By mail takes two to four weeks.

To register in person, go to your county DMV office with your proof of ownership, residency, ID, and the boat's HIN. Fill out Form REG 4 (process for Vessel Registration or Renewal). The DMV staff will check your documents, calculate the fee based on the boat's length and motor type, and issue your registration certificate on the spot. You pay the fee at that time.

To register by mail, complete Form REG 4 and mail it with copies of your proof of ownership, residency, and ID to the DMV office in the county where the boat will be kept. Include a check or money order for the registration fee. The DMV will process your process and mail your registration certificate back to you. Call the county DMV office first to confirm the mailing address and current processing time.

You can also register online through the California DMV website if you have a California driver's license or state ID. The online process is faster than mail and you can print a temporary registration certificate when ready while the permanent one is mailed to you.

Registration fees and how long registration lasts

Fees depend on the boat's length and whether it has a motor. The DMV charges a base registration fee plus a vessel use tax. For a motorboat under 8 feet, the fee is lower than for a boat 26 feet or longer. A sailboat with no motor has a different fee structure than a motorboat of the same length.

Registration is valid for either one or two years, depending on the vessel type. Most recreational motorboats are registered for two years. Some vessels, such as documented vessels or commercial boats, may have different renewal periods. When you register, the DMV will tell you when your registration expires.

You renew registration before the expiration date. The DMV will mail you a renewal notice about 60 days before expiration. You can renew in person, by mail, or online using the same methods as initial registration. Late renewal can result in a penalty fee, so renew on time.

Registering a boat you bought from out of state

If you bought a boat outside California and are bringing it into the state, you must register it with California before using it on state waters. Bring the out-of-state title or bill of sale, proof of California residency, your ID, and the boat's HIN. The DMV will register it as a new California vessel.

If the boat was previously registered in another state, you do not need to keep that registration active. California registration replaces it. However, if you plan to use the boat in another state later, check that state's rules — some states recognize California registration, others do not.

If the boat has a lien (the seller or a bank still owns part of it), the lienholder's name must appear on the California registration. Bring documentation showing the lien, and the DMV will add it to your certificate. You cannot legally use the boat until the lien is satisfied and removed from the registration.

What to do after you register

Keep your registration certificate on board whenever you operate the boat on California waters. The certificate is a small laminated card or document. Law enforcement can stop you and ask to see it, and you must have it with you. If you lose it, contact the DMV for a replacement.

Display the registration number on the boat's hull. California assigns a registration number when you register, and you must paint or attach this number to both sides of the bow (front) in characters at least 3 inches tall. The number is usually in the format "CA 1234 AB" or similar. If you do not display it correctly, you can be cited.

Update your registration if you move to a different county, change your address, sell the boat, or change the boat's name. Contact the DMV in your new county or the county where the boat is now kept. You may need to re-register or file a transfer form.

Frequently Asked Questions

Do I need to register a kayak with a small electric motor?

Yes. California requires registration for any vessel with a motor, including electric motors. Even a small trolling motor or electric paddle motor makes the kayak subject to registration. Without registration, you cannot legally use it on California waters.

What happens if I use a motorboat without registering it?

Operating an unregistered motorboat is a violation and can result in a fine. Law enforcement can stop you and inspect your registration. If you do not have one, you may be cited and required to register before using the boat again. The fine amount varies but can be substantial.

Can I register a boat if I do not have a California driver's license?

Yes. You need proof of California residency, not a driver's license. A state ID, utility bill, lease agreement, or other document showing your current California address is acceptable. You still need a photo ID for identification purposes.

How long does it take to get a registration certificate?

In-person registration at a DMV office is completed the same day. By mail takes two to four weeks. Online registration allows you to print a temporary certificate when ready, and the permanent one arrives by mail within two to four weeks.

What if my boat does not have a hull identification number?

Very old boats may not have a HIN. The DMV can assign one during registration. Bring the boat or a photo of the hull area where the HIN would normally be located, and the DMV will issue a number and register the boat with it.