Reference

Marine VHF channels

The marine VHF channels every watchkeeper uses, with their frequencies, the DSC and AIS channels, the MF/HF GMDSS distress frequencies and the three priority signals.

VHF channels

Channel	MHz	Use
16	156.800	Distress, urgency, safety and calling. Keep a continuous watch (with DSC on 70).
70	156.525	Digital selective calling (DSC): distress alerts and calls. No voice.
06	156.300	Intership safety; on-scene SAR communication, including with aircraft.
13	156.650	Bridge-to-bridge navigation safety (1 W); widely used by ports and pilots for movements.
08	156.400	Intership.
09	156.450	Port operations and intership; often pilots, marinas.
10	156.500	Port operations and intership; often pollution response.
11	156.550	Port operations; vessel traffic services.
12	156.600	Port operations; vessel traffic services.
14	156.700	Port operations; vessel traffic services.
15	156.750	On-board communications (1 W).
17	156.850	On-board communications (1 W).
67	156.375	Intership and port operations; in the UK, small-craft safety with the coastguard.
72	156.625	Intership.
77	156.875	Intership.
AIS 1	161.975	Automatic Identification System (channel 87B).
AIS 2	162.025	Automatic Identification System (channel 88B).

Priority signals

MAYDAY
Distress: grave and imminent danger to a vessel or person; immediate help needed.
PAN-PAN
Urgency: urgent message about the safety of a vessel or person, no immediate danger (e.g. medical, disabled).
SÉCURITÉ
Safety: an important navigational or weather warning.

Each is said three times before the call. A distress call on channel 16 follows a DSC distress alert on channel 70 where possible.

MF/HF GMDSS distress frequencies

Band	DSC, kHz	Voice, kHz
MF	2187.5	2182
HF 4 MHz	4207.5	4125
HF 6 MHz	6312	6215
HF 8 MHz	8414.5	8291
HF 12 MHz	12577	12290
HF 16 MHz	16804.5	16420

Good to know

Simplex channels use one frequency (above, the ship's transmit frequency); duplex channels such as 01–05, 18–28 and 60–66, 78–88 also have a coast station frequency 4.6 MHz higher. Port, VTS and pilot channels differ from port to port: check the Admiralty List of Radio Signals or the port's own information. Some countries use their own channel plans (the US, for example).

Other frequencies: NAVTEX 518 kHz (English) and 490 kHz (national languages); EPIRBs transmit on 406 MHz with a 121.5 MHz homing signal; SARTs work on the 9 GHz (X-band) radar.

A summary for study and quick reference. The official texts (the International Code of Signals, COLREGs and their national versions) govern.

VHF channels

Priority signals

MF/HF GMDSS distress frequencies

Good to know

More tools