A beacon that nobody has registered is a noise. That is the blunt way a search-and-rescue coordinator once put it to me at a talk in Lymington, and it stuck. When a 406 MHz beacon fires, the satellite system passes a long string of digits to a rescue coordination centre within minutes. If those digits match a registration record, the duty officer instantly sees who you are, what the boat looks like, how many people are usually aboard, and a phone number to ring. If they match nothing, all they have is a position and a guess. The whole point of carrying the thing is undone by the five minutes of admin you never got round to.
I cruise a UK-flagged boat to France most summers, and the beacon paperwork is the cheapest, fastest piece of safety preparation there is. It is also free. There is no excuse for getting it wrong, and yet plenty of visiting boats do.
What the two devices actually are
An EPIRB (Emergency Position Indicating Radio Beacon) belongs to the boat. It is bigger, often float-free from a bracket, and once activated it runs for at least 48 hours at minus 20 degrees, which is the international design minimum. A PLB (Personal Locator Beacon) belongs to a person. It is smaller, you clip it to your lifejacket, and its battery commitment is lower, typically 24 hours of transmission.
Both broadcast on 406 MHz to the Cospas-Sarsat satellites and most carry a 121.5 MHz homing signal so a rescue aircraft or lifeboat can close the last mile. The 406 MHz burst is the one that carries your identity. That identity is the hex ID, and it is the single most important thing on the device.
The hex ID is your registration
Every beacon has a unique hexadecimal identity coded into the transmission. First-generation beacons use a 15-character hex ID; second-generation beacons, which have been arriving since 2023, use 23 characters. You will find it printed on a label on the casing. Write it down before you fit the beacon anywhere awkward, because reading it off a float-free bracket in a cockpit locker later is no fun.
When you register, that hex ID is what you enter. It is also the code the rescue centre matches against the database when the beacon fires. A registered hex ID with stale contact details is almost as useless as an unregistered one, so the habit to build is: register on purchase, then check the record every time you change boat, phone, or next-of-kin.
How to register a UK beacon
If your beacon is for use on a UK-flagged vessel, you register with the Maritime and Coastguard Agency through the national 406 MHz beacon service at register-406-beacons.service.gov.uk. It moved fully online and the process takes around 15 minutes. It costs nothing.
Before you start, have these to hand: the beacon hex ID, the vessel name and any registration number, the radio call sign, the MMSI if the boat carries DSC VHF, and at least one emergency contact who is not aboard. The requirement to register is set out in the MCA's MSN 1924, and from 15 April 2026 the rules tightened: every EPIRB carried on a ship must be registered, and any PLB carried aboard must be registered by its owner. If you bought a secondhand boat with a beacon already fitted, the previous owner's details are almost certainly still in the system. Transfer it into your name before you sail.
A registered UK beacon works anywhere in the world. The Cospas-Sarsat system is global, and the alert routes back to the UK Mission Control Centre, which holds your registration, then on to whichever rescue centre is nearest the position. So a UK beacon firing off the Brittany coast is still tied to your UK record. That matters for how you fill in the next part.
Why French waters change nothing, and everything
The registration database is flag-state business, not where-you-happen-to-be business. France will not ask you to re-register a foreign beacon, and there is no separate French portal for a UK boat. But three practical points are worth knowing once you are cruising in France.
First, the beacon's identity travels with the alert, so an out-of-date UK record will slow down a French rescue. CROSS Gris-Nez in the eastern Channel, CROSS Jobourg in the central Channel, and CROSS Corsen off Brittany all receive beacon alerts around the clock. If your registration says the boat is a 9-metre sloop with two adults aboard and you are now cruising four-up on a different hull, you have handed the coordinator bad information at the worst moment.
Second, France's own equipment rules under Division 240 require a registered EPIRB for boats operating in the offshore zone, beyond 60 nautical miles from a shelter, and the regulator is explicit that the beacon must be registered to count. Those rules apply to any boat under 24 metres in French waters regardless of flag, so if you plan a Biscay crossing or a long offshore leg, the beacon is not optional kit. I cover the wider equipment list in the Division 240 safety equipment for visiting boats piece.
Third, your beacon and your VHF want to agree with each other. If the boat carries DSC VHF, the VHF licence, DSC and MMSI for France record and the beacon record should both point at the same vessel and the same contacts. Two safety systems telling a rescue centre two different stories is the kind of thing that costs an hour.
EPIRB or PLB: which one to carry
Visitors often ask whether they need both, and the honest answer is that it depends on the boat and the cruising. An EPIRB is the better single choice for a boat, because it is tied to the vessel, it transmits for at least 48 hours, and a float-free version deploys itself if the boat sinks before anyone can grab it. If you carry one device and you sail offshore, make it an EPIRB.
A PLB is the better single choice for an individual, especially the on-watch crew at night, because it lives on the lifejacket and goes into the water with the person. The trade-off is the shorter battery commitment, around 24 hours, and the smaller antenna, which can struggle to keep a clear view of the sky in a rough sea when the casualty is low in the water. For a crew that does night passages on the French coast, the combination I prefer is a float-free EPIRB on the boat and a PLB on each lifejacket, so the vessel and every person are covered separately.
Whatever the mix, each device is registered on its own hex ID. A PLB registered to you, the person, and an EPIRB registered to the boat are two records, not one. Both have to be current.
A short test you can run on the pontoon
Most beacons have a self-test button that confirms the unit is working without firing a real alert. Run it. Read the hex ID off the case and check it letter for letter against your registration printout. Confirm the registration shows the right vessel, the right number of usual crew, and a contact who answers the phone. Check the battery expiry date stamped on the case; a 406 beacon battery typically lasts around 6 years from manufacture, and a beacon with a dead battery is decoration.
Do that once at the start of the season and you are done. It is fifteen minutes of admin against the one day you might genuinely need the satellites to know your name.
The wider safety habit
A beacon sits inside a chain of safety decisions, not on its own. It is the thing that brings help to you; the French distress and safety call procedure is the thing you do first if you still have a working VHF and time to use it. The beacon is the backup for when the radio cannot reach anyone or the situation has moved faster than a voice call. Register it, test it, and then forget about it, which is exactly what you want from a piece of kit you hope never to use.
