Everything You Need To Know About Obtaining Your MMSI Number
The number one question we get all the time is “How do I get my MMSI number?”, so we decided to do this post for our inquiring clients (and add a few VHF tips).
Although VHF radios are not required on recreational boats under 65.5 feet long, you should have one for the obvious safety reasons. It allows instant communication between your boat and other boats, marinas, bridges, and the United States Coast Guard (USCG) in case you run into trouble on the water. So, you need one. There are also requirements that you need to have when you have a VHF. One is the Maritime Mobile Service Identity, or MMSI which is a 9-digit number used to identify a ship via radio.
If you are going to be traveling to a foreign port you’re required by law to have a radio on your vessel and you need an MMSI number. Also, the MMSI number is required for all AIS transponders to transmit your identity over the air. The digital DSC Emergency Alert will not function without the MMSI number. If you are a US documented or registered vessel and are required to have MMSI # then you are also required to have an FCC Ship Station License & Restricted Radio Operators.
Approved Organizations
There are approved boat owners’ organization that assign MMSI numbers. The FCC and US Coast Guard authorize organizations to assign domestic MMSI numbers. The application process is very simple. You receive your MMSI number immediately so it’s not a hassle.
As of publication, authorized organizations include:
Boat US: https://www.boatus.com/MMSI/MMSI/Home
US Power Squadron: http://www.usps.org/php/mmsi_new
You may have to join the boating organization you’re going to use before it will assign you an MMSI. Others, such as Boat US, assign MMSI numbers to non-members for a fee. However, if you’re a member of the organization, you can get your MMSI number for free, as well as having access to other organization resources. For instance, the membership may include tow service or other assistance if you run into problems.
Here’s The Step-by-Step: How to Register for an MMSI
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Gather your boat info (make, model, registration number, owner info).
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Visit BoatUS or US Power Squadron (links above).
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Fill out the online form which takes about 10 minutes.
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Print your confirmation and program your MMSI into your radio.
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Test your DSC function with another VHF or a marina station.
Once you log on the chosen site, you are led through the process. It’s very easy. You need to have your boat information. Immediately after you submit your application, a confirmation page will appear with your new MMSI number. Usually, you will receive this information through a confirmation email as well. Print at least 2 copies, one for your boat and one for your home records of the MMSI number. Now you’re ready to program the MMSi into your radio.
Check your VHF’s manual. There should be programming instructions, which vary by radio, so check your product’s user manual. Read the directions carefully and enter your MMSI number precisely. Most radios can only be programmed with an MMSI number once, so it you make a mistake, you may have to send your radio back to the manufacturer to get it cleared!
What Happens to Your MMSI Number When You Sell or Buy a Boat?
One of the most common questions we get is about MMSI numbers during boat ownership transfers.
Here’s what you need to know:
If You’re Selling Your Boat: Your MMSI number stays with the boat, not with you as the owner. Before you complete the sale, you should contact the organization that issued your MMSI (Boat US, US Power Squadron, etc.) and inform them of the ownership transfer. They’ll update their records and the new owner will need to re-register the MMSI under their information. This ensures that if there’s an emergency, the Coast Guard contacts the right person.
If You’re Buying a Boat: First, check if the boat already has an MMSI number programmed into the VHF radio. You’ll need to contact the issuing organization to update the registration with your contact information, vessel details, and emergency contacts. Remember, most VHF radios can only be programmed with an MMSI once, so if the previous owner’s number is already in there, you may need to have the radio sent back to the manufacturer to clear it before programming your information. Some newer radios allow reprogramming, so check your manual first.
The key takeaway: Never leave a boat with someone else’s MMSI and contact information programmed in the radio. In an emergency, the Coast Guard needs to reach YOU, not the previous owner.
VHF Etiquette and Channels Every Boater Should Know
If you’re boating on San Francisco Bay, knowing your local VHF channels and radio etiquette can make all the difference. With heavy commercial ship traffic, changing weather, and frequent recreational boating events, clear communication keeps everyone safe and informed.
Common VHF Marine Channels
Here’s a quick reference for recreational boaters:
| Channel | Use |
|---|---|
| 16 | Distress, hailing, and safety calls (monitored by the USCG) |
| 09 | Secondary hailing channel for non-commercial vessels |
| 22A | U.S. Coast Guard public information broadcasts (weather, safety alerts) |
| 68, 69, 71, 72, 78A | Working channels for recreational boaters |
| 13 | Bridge-to-bridge navigation (commercial traffic) |
| 14 | Vessel Traffic Service (VTS) – ship coordination (especially in busy areas like San Francisco Bay) |
| 70 | Digital Selective Calling (DSC) – automatic distress and identity signaling |
Keeping a laminated copy of this channel list near your helm is a smart move, especially for guests or new crew members.
VHF Radio Etiquette
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Keep Channel 16 clear. This is the hailing and distress channel, and it’s monitored 24/7 by the U.S. Coast Guard. Hail another vessel on Channel 16, then immediately switch to a working channel once they respond.
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Be brief and clear. Identify yourself and your vessel’s name, keep your message short, and always speak slowly and distinctly.
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Don’t use slang or chatter. Channel 16 is not for casual conversation — think of it like the emergency lane on a freeway.
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Perform a radio check on the right channel. Use Channel 09 or 68 to make a radio check. Never test on Channel 16.
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Listen before transmitting. Make sure no one else is talking before pressing the mic button to avoid stepping on another transmission.
Local Tip:
If you’re near the Golden Gate Bridge or approaching shipping lanes, monitor Channel 14. Large commercial ships use this channel to announce their movements as they enter and exit the Bay. Listening in can help you anticipate traffic and stay clear.
Recommended VHF Radios for Bay Boaters
If you’re shopping for your first or next radio, look for models that include DSC (Digital Selective Calling) and GPS capability, so your exact location can be transmitted automatically in an emergency.
Some reliable models for Bay cruisers include:
Hands-On Training: Build Skills, Confidence & Global Freedom
Reading about boating safety is one thing — experiencing it firsthand is where true skill (and calm) begins. Our Private Lessons give you that experience. Whether you want to improve your close-quarters maneuvering, docking finesse, or radio communication under pressure, our certified instructors coach you one-on-one on both sail and powerboats right here on San Francisco Bay.
You’ll learn practical techniques for:
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Handling wind, current, and chop with confidence
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Navigation, anchoring, and docking in real conditions
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Communicating clearly using VHF, hand signals, and crew coordination
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Managing emergency procedures and weather changes
We meet you at your level — beginner or advanced — and tailor every session to your goals and vessel type.
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We also offer training and certification for your Bareboat Charter Certification, SLC or SLC-p International Boating License — the credential recognized worldwide for bareboat charters. You’ll learn everything from coastal navigation and COLREGS to radio protocols and anchoring techniques.
Our instructors help you meet the licensing requirements efficiently, so you can sail or powerboat anywhere in the world with full confidence and legal readiness.
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If you’re not ready to buy a boat, no problem — you don’t need to. Through our Private Boating Clubs, you can train, learn, and enjoy the water without ownership hassles. Members get access to our fleet of premium yachts and powerboats, plus special events, day sails, and retreats designed to build real seamanship and community.
It’s the easiest and most enjoyable way to:
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Continue practicing after your lessons
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Enjoy monthly sailing and power outings
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Join a community of like-minded adventure seekers
Think of it as your “all-access pass” to the water — where you can learn, grow, and play while building a lifestyle around confidence and calm at sea.
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