How to Register, Test, and Maintain an EPIRB or PLB

I bought an EPIRB — how do I register it, self-test it, and keep the battery current?

A 406 MHz beacon is only as good as its registration: when it fires, search-and-rescue pulls your contact info, vessel, and emergency contacts straight from the NOAA database, which is what turns a raw satellite hit into a fast, targeted rescue. Registration with NOAA is free and legally required, takes about 15 minutes online, and must be renewed every two years. The built-in self-test confirms the electronics and battery on demand (run it monthly, sparingly), but the battery itself has a hard expiration date and almost always requires a manufacturer-authorized service center to replace — it is not a DIY swap. An unregistered, expired, or untested beacon is the single most common failure mode, and it is entirely preventable.

ℹ️ Reference only: For general reference only. This guide does not guarantee any result — every home is different. Verify against your local building codes and a licensed professional before acting, especially for electrical, gas, plumbing, structural, or roof work.

💵 Registration: free. Self-test: free. HRU replacement: ~$40-$120 DIY. EPIRB battery replacement + recertification at an authorized service center: ~$150-$300+ (sometimes approaching the cost of a new unit, so compare). Owner-replaceable PLB battery (where permitted): ~$30-$80. ⏱ Registration ~15 minutes online; monthly self-test under a minute; seasonal inspection ~10 minutes; battery service turnaround 1-2 weeks if shipped to a service center. ● Use caution

Safety: Never activate a 406 MHz beacon except in a genuine life-threatening emergency — a false alert launches a real Coast Guard / SAR response, endangers rescuers, and can bring fines. Use only the self-test mode for checks, and follow the manual's exact button sequence so a "test" doesn't become a real alert. This is life-saving safety gear: an unregistered, expired, or untested beacon can fail exactly when you're in the water, offshore, or going down — failure modes here are about being lost at sea, hypothermia, and drowning, not a routine repair. Do not open a sealed EPIRB to change the battery yourself; breaking the waterproof seal can let water in and kill the unit when you need it most.

Common causes

Beacon never registered, or registration lapsed past the 2-year renewal — SAR gets a position but no owner, vessel, or emergency-contact data, slowing the response (most common)
Quick check:
Battery past its printed expiration date (typically 5-6 years from manufacture/service), so it may not transmit at full power or duration when activated (common)
Quick check:
Hydrostatic release unit (HRU) on a Category I EPIRB expired, so the beacon won't float free and auto-activate if the vessel sinks (common)
Quick check:
Self-test never run, so a dead battery or failed electronics goes unnoticed until the real emergency (common)
Quick check:
Excessive self-testing — each test draws from the non-rechargeable battery; running it daily or holding it too long shortens usable life (less common)
Quick check:

How to fix it

Read the manual first and find the beacon's 15-character UIN/HEX ID — it's printed on the case label and is what you register. Confirm whether it's an EPIRB (registered to a vessel) or a PLB (registered to a person); both register to the same NOAA database but under different categories.
Register free at the U.S. official site, beaconregistration.noaa.gov, before the beacon ever leaves the dock. Enter the HEX ID, vessel name/registration or your personal info, and at least two 24/7 emergency contacts who know your boating plans. Foreign-flagged or non-U.S. owners register with their own country's program (the beacon is coded to a country, so it must be registered there).
Print the NOAA confirmation and apply the proof-of-registration decal they mail (or that prints out) onto the beacon body. Set a calendar reminder to renew every 2 years and to update NOAA immediately whenever you change boats, phone numbers, or emergency contacts.
Run the built-in self-test monthly: press and hold the TEST button per the manual until you get the pass indication (a specific LED flash/strobe and/or audible chirp). Follow the manual's button sequence exactly — on some units holding the wrong button or holding too long can trigger a real activation. The test verifies battery voltage, the 406 MHz transmitter, and on GPS models the GPS lock. Do NOT do a live activation — that triggers a real SAR response and a fine for a false alert.
If the beacon has a GPS self-test mode, run it occasionally in open sky (not inside the cabin) so it can confirm a satellite fix; follow the manual's limit on how many tests per battery life. (In a real activation the beacon also puts out a 121.5 MHz homing signal that rescuers use for final close-in localization — nothing to maintain, but it's why an in-date battery matters.)
Check the battery expiration date printed on the case at the start of each season. When it nears expiry, send the unit to a manufacturer-authorized service center for battery replacement and recertification — on most EPIRBs the battery is sealed for waterproof integrity and is not a user-replaceable part. A few PLBs allow owner battery changes; only do so if the manual explicitly says it and use the exact specified battery, or you void the waterproof rating and certification.
Know your category: a Category I EPIRB is mounted in a float-free bracket with a hydrostatic release unit (HRU) that frees and auto-activates the beacon if the boat sinks; a Category II is manually deployed and has no HRU. For a Category I, check the HRU expiration (commonly ~2 years) and replace it on schedule — it's a low-cost part. Mount the bracket where it can release unobstructed, high and clear, per the manufacturer's instructions.
Inspect the case for cracks, corroded contacts, a clear/undamaged lens over the strobe, and an intact lanyard. Store the beacon in its bracket in an accessible spot, not buried in a locker, and brief crew on where it is and how to activate it.
Verify proper operation as a system: registered (decal on case), self-test passing, battery in date, HRU in date (Cat I). All four green = the beacon will do its job.

DIY or call a pro?

Registration, self-testing, visual inspection, and HRU replacement are straightforward owner tasks — do them yourself. Battery replacement and recertification are a pro job for nearly all EPIRBs and many PLBs: the sealed, waterproof housing must be reopened, re-sealed, and the unit re-tested by a manufacturer-authorized service center to keep its certification and waterproof rating valid.

Tools & parts

The beacon's manual (for exact self-test procedure and battery type/limits)
15-character UIN/HEX ID from the case label
Internet access for beaconregistration.noaa.gov
Two 24/7 emergency contacts and your float-plan info
Replacement hydrostatic release unit (HRU) matched to your Category I EPIRB model
Manufacturer-authorized service center for battery replacement and recertification
NOAA proof-of-registration decal
Calendar reminders for 2-year registration renewal, battery expiry, and HRU expiry

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Based on: NOAA Search and Rescue Satellite-Aided Tracking (SARSAT) / beaconregistration.noaa.gov; U.S. Coast Guard and USCG Auxiliary; Federal Communications Commission (FCC) beacon regulations; Cospas-Sarsat international program; BoatUS Foundation for Boating Safety and Clean Water; ABYC (American Boat & Yacht Council); NMMA (National Marine Manufacturers Association); Beacon manufacturer service guidance (e.g., ACR Electronics, Ocean Signal)

General marine-maintenance guidance, not a substitute for a qualified marine technician or surveyor. Boats and conditions vary; for fuel, electrical, fire, or structural issues — or anything safety-critical — consult a professional. Always follow your engine and equipment manuals.