Marine Radio Guide
VHF Communication for Boating Safety
Marine VHF is the standard for boat-to-boat and boat-to-Coast Guard communication. Cell phones don't work offshore, but VHF does, with a 25-watt fixed-mount reaching 20-plus miles. DSC-equipped radios transmit your GPS position automatically with a single button press in a distress situation.
Getting Started with Marine VHF
Essential boating communication
Best Marine VHF Radios 2026
Top picks for handheld marine VHF radios from Standard Horizon, Uniden, and more. DSC-equipped options for safety.
View GuideMarine Radio Licensing & MMSI
Understanding MMSI numbers, DSC registration, and when you need a marine radio license.
View GuideEmergency Prep Gear
Complete emergency communication setup including marine, weather, and scanner options.
View GuideWeather Alert Radios
NOAA weather alerts complement marine VHF for complete maritime safety coverage.
View GuideWhy VHF Marine Radio?
Cell coverage ends a few miles from shore. VHF is how boats call the Coast Guard, hail marinas, get weather, and coordinate with nearby vessels.
Coast Guard Direct
Channel 16 connects you directly to Coast Guard for emergencies, search and rescue, and distress calls.
DSC Position Alerts
Digital Selective Calling transmits your GPS position automatically with distress calls. One-button emergency.
Works Offshore
25 watts of power means 20+ mile range, far beyond where cell service ends. Essential for offshore trips.
Weather Updates
NOAA weather broadcasts on WX channels. Get marine forecasts, storm warnings, and sea conditions.
Key Marine VHF Channels
Know the essential frequencies
Channel 16 (156.8 MHz)
DISTRESS & CALLING
International distress, safety, and calling channel. All vessels must monitor. Call the Coast Guard here, then switch to a working channel.
Channel 22A (157.1 MHz)
COAST GUARD
Coast Guard liaison and marine safety broadcasts. After initial contact on 16, the Coast Guard may direct you here.
Channel 9 (156.45 MHz)
CALLING (ALTERNATE)
Secondary calling channel in some areas. Some boaters prefer this for non-emergency hailing to keep 16 clear.
WX Channels
NOAA WEATHER
Seven dedicated weather channels (WX1-WX7) broadcast continuous NOAA forecasts. Essential for planning and storm tracking.
Bridge-to-Bridge Channels
Channels 13 and 67 are used for navigation and maneuvering, especially near bridges, in narrow passages, and for communicating with large commercial vessels. Use 1-watt power on Channel 13.
Licensing Requirements
When you need a license for marine VHF
No License Required
- Recreational boaters in U.S. waters
- Domestic voyages (not international)
- Non-commercial vessels
- Still need MMSI for DSC features
License Required
- International voyages
- Commercial vessels
- Vessels required to carry radio
- Using SSB or satellite communications
MMSI Registration is Free
Even without a license, you should register for an MMSI (Maritime Mobile Service Identity) number. It's free for recreational boaters through BoatUS or Sea Tow, and it's required to use DSC emergency features. Learn how to get your MMSI.
Frequently Asked Questions
Do I need a license for a marine VHF radio?
For recreational boaters in U.S. waters on domestic voyages: no license required. However, you still need to register for an MMSI number (free) to use DSC emergency features. Commercial vessels, international voyages, and vessels required by regulation to carry radio do need an FCC ship station license.
What is an MMSI number and how do I get one?
MMSI (Maritime Mobile Service Identity) is a unique 9-digit identifier for your vessel, similar to a phone number. It's required for DSC features to work. Recreational boaters can get an MMSI free through BoatUS (boatus.com/mmsi) or Sea Tow. The number is programmed into your radio and transmitted with distress calls.
What is DSC and why does it matter?
DSC (Digital Selective Calling) is a one-button emergency system. When connected to GPS, pressing the red distress button automatically transmits your position, vessel identity (MMSI), and nature of emergency to the Coast Guard and nearby vessels. It's like 911 for boats but includes your exact location automatically.
How far can a marine VHF radio reach?
Typically 5-15 miles for handheld radios (5 watts) and 15-25+ miles for fixed-mount radios (25 watts). VHF is line-of-sight, so antenna height matters enormously. A masthead antenna can extend range significantly. For offshore voyages beyond VHF range, SSB (single sideband) or satellite communication is needed.
What's the difference between handheld and fixed-mount marine radios?
Handheld radios: 5-6 watts, battery powered, portable, good for dinghies and backup. Fixed-mount radios: 25 watts, hardwired power, better range, permanent installation. Most serious boaters have both—a fixed-mount as the primary radio and a waterproof handheld as backup or for use in the dinghy.
Why can't I just use my phone instead of a marine radio?
Cell phones don't work offshore—coverage ends a few miles from shore. Even near shore, VHF is monitored by the Coast Guard, other vessels, and marinas. If you call 911, dispatchers have no maritime expertise and can't coordinate marine rescue. Channel 16 connects you directly to Coast Guard and any vessel within radio range. It's the maritime 911.
Get the right radio before you need it
VHF is how offshore distress calls happen. Channel 16 is monitored by the Coast Guard and every properly equipped vessel nearby. A phone call to 911 from a sinking boat accomplishes very little. A DSC distress call transmits your position to everyone in range.