Call Mayday from a Marine Vessel

Originally from the French term "venez m'aider" meaning "come help me", the Mayday signal is used internationally to signal life-threatening distress; it's similar to dialing emergency services or using morse code SOS. While it is used in various emergency situations, this article is concerned with its use in maritime activities. Understanding how to make a Mayday call is an essential part of being ready to crew any boat. Learning this important skill will save lives because helping Coast Guard or other sea rescue officials get to you accurately and swiftly means you'll get out of a stressful situation that much faster. This article will help you know how to respond in the event of an emergency, as well as how to implement the Mayday procedures.


  1. Stay calm. In the event of an emergency, such as from a sinking vessel, a disabled vessel, an on-board fire, sudden mass illness or pirate or hijacking activity, it's important to remain as calm as possible so that you can act with a level head. If there is help close by, the help will be able to help you. You won't be able to guess at the proximity of help, so it's best to stop worrying and start acting, while waiting for assistance to reach you.
    • Evaluate the situation. Understand that you are to make a Mayday call only if you are in a serious distress situation where there is an immediate or imminent threat to life or loss of property. This includes fire, injury, the vessel taking on water, or people fallen overboard, etc.
    • If your vessel is sinking, if you're in a life-threatening situation such as a fire or explosion, if pirates are seeking to board your boat, or if everyone on the boat suddenly succumbs to a strange illness that prevents crewing of the vessel, the Mayday call is appropriate.
    • If your mast or other rigging breaks, or if one person falls ill but it's not life-threatening, send a Pan-Pan call instead.
  2. Contact the Coastguard Through VHF Radio. Tune your radio to marine VHF radio channel one-six (16) or Frequency 161.400 or 156.800 MHz; marine MF/SSB on 2182 kHz. These channels are constantly monitored by Coast Guard and other sea rescue authorities (as well as nearby boaters) so are more likely to be responded to. When on a boat, the radio should be on, and tuned to channel 16, even if there is no emergency. (Most newer radios have the option of multiple channel monitoring. Ensure 16 is one of them) If you cannot communicate on 16, use any channel with traffic on it; once you do so, protocol will expect all traffic on that channel to cease unless it relates to the Mayday call, so as to assist you.[1]
    • Push the red "DSC" button, if there is one. Newer radios have a button labeled "DSC" (Digital Select Calling), which transmits the GPS coordinates to the coastguard along with a Mayday beacon. Older radios do not have this, also, if the radio is not connected to a GPS unit, it will have no coordinates to transmit (although the Mayday beacon will still go through). Remember though, that even if the radio has a DSC button, don't let the digital mayday transmission do all the work. You have some needed information that the transmitter doesn't, such as the urgency of the situation, and a description of what is happening.
    • Listen to the channel. Ensure there are no other emergency transmissions, or other chatter that will cut you off. Although it is absolutely OK to cut off non-emergency chatter when you are in a Distress Situation, they may come back and cut you off afterward. If you don't have time to consider this, just get on with sending out your distress signal.
  3. Take a few deep breaths and rehearse what you are going to say. Remain calm. Keep in mind:
    • Mayday is always stated three times in a row, to ensure that it is heard accurately, and to distinguish it from radio talk about receipt of a Mayday call.
    • It is essential to speak clearly, slowly, and split numbers. For example, say One-Five instead of Fifteen.
    • If you know the phonetic alphabet - Use it! (i.e. Alpha, Bravo, Charlie etc.)
    • Hold the microphone a few inches away from your mouth.
    • Stay calm, rushing through the transmission is not going to help you get help any faster.
  4. Make the call. Press and hold the talk button (usually labeled "PTT" ("Push To Talk")) and say something along the lines of:
    • Mayday, Mayday, Mayday. This is [your name] on the [vessel name x 3]. Callsign [state your callsign]. (If you’re using a VHF-DSC radio, provide your Maritime Mobile Service Identity (MMSI)). BREAK.
    • Release the microphone button momentarily to ensure the channel is clear. Press again.
    • Mayday. The vessel ["vessel name"] is located [current position, speed and bearing]. (For example, Position 54 25 North 016 33 West, drifting at one knot with a bearing of 228 degrees). We are a [sailboat, motorboat, etc.] experiencing [distress situation] and are in need of immediate assistance.
    • There are [number of people on board] with [injuries/other additional information]. Length, color, rig of boat can be helpful, as well as any intention to deploy life boats, etc.
    • This is [vessel name], [callsign/MMSI]. Over.
    • If you don't have all of this information, it's okay. Give the information that you DO have.
  5. Wait for a response. Let go of the Talk button (unkey). Wait for a response. If you do not hear one after 15 seconds, repeat the call again.
    • While waiting, prepare flares, life rafts, life jackets, gather emergency supplies, call orders to others to prepare, etc. Stay calm and set an example for everyone else to follow.
    • If you still have no reply and don't have to leave your boat yet, listen on another channel and break in with your distress call. It may be that your transmitter is too weak or not responding well, so ask other vessels to transmit your distress call to shore.
  6. Follow instructions unless you need to evacuate immediately. You may be asked to switch to a Coast Guard 'working channel'. You may be told, for example, to switch to another channel. If so, confirm by saying something like, "Confirmed, Switching to [channel number]."
    • In the event that you need to leave immediately after making a Mayday call, inform authorities of what you're doing as part of the additional information in the Mayday message, for example, "We are taking to lifeboat/deploying a life raft".
    • If you're able to maintain radio contact, follow all the radio operator's instructions. They are trained professionals and it is their job to help you
  7. Stand by. Keep one person stand-by on the radio for as long as possible.

Relaying a Mayday distress signal

A second vessel not in distress may find itself in the position of having to relay the Mayday signal on behalf of the distressed vessel. If you find yourself in this situation, here is what to do:

  1. Listen to the radio frequency. If it is clear that the Coast Guard or other sea rescue agency has not responded after a single repetition and a two minute wait, you must seek to contact the Coast Guard or other sea rescue agency on behalf of the distressed vessel.
  2. Say: Mayday relay, Mayday relay, Mayday relay. This is the ["your vessel and callsign"]. The following distress call was received from ["distressed vessel's name"]. The reported position of the ["distressed vessel's name"] is ["their reported position"]. Over.


  1. For an incident of lesser gravity but where your vessel is still in a difficult situation, such as mechanical breakdown, broken masts, or a non life-threatening medical problem affecting a crew member, etc., use the pan-pan (pronounced "pon-pon") call instead of the Mayday call.
    • Say "Pan Pan, Pan Pan, Pan Pan."
    • Provide your vessel's name and callsign.
    • State your position. Give the nature of the problem (for example, "Engines have ceased to work", "mast has snapped, storm coming" etc.)
    • State intended action.
    • Over.
  2. Wait for instructions.


  • The Maritime Mobile Service Identity (MMSI) is a nine-digit number that is registered; it further identifies your boat to the Coast Guard.
  • Rehearse the call often; in the event of a real emergency, you will fall back on what you have practiced.
  • If you need to abandon ship, notify the radio operator.
  • If you are asked to switch to a different, radio frequency, clearly state the new frequency you are switching to and state, "If no contact in xx seconds (usually 30 seconds), return to this frequency". Then, if for some reason you are not able to establish contact on the new frequency, both parties know what is expected and communication can be re-established on the original frequency.
  • Be clear and precise in your call, it will help you get help quicker.
  • Prior to the voyage, good procedure is to identify all possible ports of call for use in an emergency. Knowing where these are located can help to reassure you that help will be on its way.
  • If you have an EPIRB, activate it.
  • If you hear a Mayday call do not transmit. Pay close attention however to the information the stricken vessel provides (position, nature of the distress, etc.). There is a possibility that YOU may be the closest vessel able to render assistance. The Coast Guard will usually rebroadcast the mayday information and ask if there are any vessels in the vicinity able to help. If you're on channel 16 during a Mayday, only use it if you are responding to the distress. Otherwise, maintain Silence Mayday, pronounced "seelonce mayday".
  • Cell phones or mobile phones should only be used as a secondary source of sending a Mayday call. Often there is another nearby boater able to assist and can only do so if they are able to hear your mayday call.
  • There is etiquette involved in the use of a VHF radio. If you intend to go boating often, you should familiarize yourself with it.[2]


  • Do not transmit a mayday unless loss of ship(s) and/or person is an imminent threat.
  • Do not transmit a mayday for events such as running aground (with no damage), loss of power, or similar happenings. In these cases, help may be needed, but an urgent mayday is not.
  • Making a false mayday call can be punishable by law, and in many countries is punishable under criminal law because it is a serious action meant to protect lives, not throw emergency services into chaos. Authorities can now identify your radio, and you will be fined or even prosecuted if you're caught! Do not practice a mayday call on the radio; practice with a friend.

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