Do EPIRBs and PLBs require a subscription?

There is a persistent belief that emergency beacons come with a bill attached, and it costs people the purchase. It comes from a real thing — satellite messengers do charge monthly — but the two products are not the same, and the difference matters most on the day you find out.

Do EPIRBs and PLBs require a subscription?

No. A 406 MHz beacon transmits to Cospas-Sarsat, a search-and-rescue satellite system run cooperatively by participating governments. There is no subscription, no activation charge and no airtime fee. You buy the device and it works.

That design decision is unusual enough to be worth sitting with. Almost every other connected device you own is a recurring payment wearing a hardware costume. A distress beacon is the opposite: a lump of electronics that will still summon a rescue coordination centre after a decade in a locker, with no card on file and nothing to renew.

Then what is the subscription people are thinking of?

Satellite messengers. Devices like Garmin’s inReach or Icom’s IC-SAT100 push-to-talk run on commercial satellite networks — Iridium — and those networks bill by the month. Without an active plan, a messenger is an expensive paperweight, including its SOS button.

Both categories are legitimate. They just answer different questions.

	406 MHz beacon (EPIRB / PLB)	Satellite messenger
Network	Cospas-Sarsat, government-run	Commercial (e.g. Iridium)
Ongoing cost	None	Monthly or annual plan
Message	One: distress, identity, position	Two-way text, tracking, plus SOS
Works unpaid	Yes	No
Registration	Required, free	Account required
Typical brands	ACR, McMurdo	Garmin, Icom

The honest summary: a messenger is how you tell someone you’ll be late. A beacon is how you tell a government you are in serious trouble. Plenty of people offshore carry both and think of the beacon as the layer that survives an expired credit card.

EPIRB, PLB or ELT — which one do you need?

An EPIRB is registered to a vessel. It lives aboard, it is sized to be found, and float-free models release automatically from their bracket via a hydrostatic release as the boat goes down — which matters precisely because the scenario is one where nobody has a free hand.

A PLB is registered to a person. It goes in a pocket or on a harness and it goes where you go, including off the boat, up a mountain or into a canyon. Smaller battery, shorter transmit duration, but it is on you.

An ELT is the aviation equivalent, fitted to aircraft, and outside what this page covers.

If you own a boat and go offshore, the common answer is an EPIRB on the vessel and a PLB on the skipper. If you are a paddler, a hunter or a climber, the PLB is the whole conversation.

What is the free step almost everyone skips?

Registration. In the US, 406 MHz beacons register with NOAA, it costs nothing, and it takes a few minutes.

Here is why it is not paperwork. An unregistered beacon still transmits a position, and a rescue will still be launched. What the rescue coordination centre does not get is your name, your vessel, its description, or a phone number for someone who knows where you went. That last item is what lets them resolve a false alert with a phone call instead of a helicopter, and it is what lets them know they are looking for a 32-foot sloop with three people aboard rather than an unknown signal in the water.

Update the registration when you sell the boat. A beacon registered to a previous owner is worse than an unregistered one, because it produces confident, wrong information at the worst possible moment. If you buy a used vessel, assume the beacon is registered to somebody else until you have checked.

This is the same failure as an unprogrammed MMSI on a DSC radio — see Uniden and Standard Horizon. The hardware works perfectly and nobody knows who you are.

What does actually cost money?

Three things, none of them monthly.

Battery replacement. Every beacon carries a manufacturer-stated replacement date, printed on the unit. It is typically a service-centre operation rather than a user-swappable cell. Check the date on the beacon in front of you rather than a figure from an article, including this one.

Hydrostatic release replacement, on float-free EPIRBs. The release is the part that lets the beacon leave the bracket on its own, and it has its own expiry.

Servicing, depending on the model, the flag state and whether the vessel is commercial.

Budget for those the way you budget for a liferaft repack — as the real cost of ownership, decided before you buy rather than discovered afterwards.

Does the brand matter?

Less than the layer does. ACR Electronics of Fort Lauderdale and McMurdo of Portsmouth are the two names most people will encounter, they run on the same satellite system, and the real differences are availability, service network and which one your dealer stocks.

One caution on McMurdo specifically: the brand has changed hands more than once recently — Seas Of Solutions acquired Orolia’s maritime brands in 2021, and a widely repeated claim that Safran now owns McMurdo is not accurate. Since a beacon is a fifteen-year relationship with battery and service intervals in it, “who honours this and where do I send it” is a fair question to ask your dealer before you buy.

Where the beacon sits in the chain

A beacon starts a search. It does not finish one.

Satellite alert — ACR or McMurdo tells a rescue centre who and where. Radio — Icom or Standard Horizon talks to vessels nearby, with DSC as the one-button version. Visual — Orion flares and smoke say here, now, look to the aircraft or boat that has arrived in the area. Flotation — Mustang or Onyx keeps you at the surface while all of that happens.

No layer substitutes for another, and the cheapest one on that list is the one people most often skip.