Rescue 21 for Boaters

Rescue 21 will increase the Coast Guard’s ability to respond to distress calls in the coastal zone. However, you can help us improve response time by using a marine-band VHF-radio equipped with digital selective calling (DSC).

Why use a radio equipped with DSC?

With the push of a button, your DSC radio will send an automated digital distress alert containing your Maritime Mobile Service Identity (MMSI) number, position, if interfaced with GPS, and the nature of distress to other DSC-equipped vessels and rescue facilities. As a result, the Coast Guard is able to respond more quickly and to more accurately identify the location of the distress call. For more information on DSC and how to send alerts and test your equipment, check out the Coast Guard’s Navigation Center website.

Get your MMSI number

To obtain and register your MMSI number, check out the Boat U.S. and Sea Tow MMSI programs. Both have been certified by the Federal Communications Commission and the Coast Guard.

Vessel Safety Check

The Coast Guard Auxiliary is available to help local boaters ensure that their radios are in good working order. Click here to schedule a vessel safety check in your local area. Examiners also can educate boaters on the importance of properly connecting Global Positioning System equipment to your VHF-radio to ensure a DSC transmission provides proper position information.

Sending a DSC message directly to Coast Guard Sectors

DSC distress alerts will be received by the Coast Guard when Rescue 21 is fully operational in your area. Listed below are the MMSI numbers for Coast Guard sectors and groups that have Rescue 21. These numbers can be used to send a DSC message directly to Coast Guard units.

Rescue 21 VHF DSC MMSI Numbers