If a life is at risk, or could be soon, it’s an emergency: a MAYDAY on VHF Channel 16 if you have a radio, and 911 by phone. If nobody’s in danger and the problem is mechanical (dead engine, out of gas, dead battery, soft grounding), it’s a tow: TowBoatUS or Sea Tow. Members are covered; without a membership you get the bill, which Sea Tow puts at $950 on average. On inland lakes there’s often no Coast Guard nearby, and 911 reaches the sheriff’s marine unit or local fire rescue.
Someone in the water, an injury, fire, taking on water, drifting toward rocks, a dam or a shipping channel, darkness or a storm coming in. Yes → MAYDAY on VHF Channel 16, and 911. Don’t downgrade a maybe: responders would rather stand down than start late.
That’s a tow, not a rescue. Call TowBoatUS (24/7 dispatch 800-391-4869, or “TowBoatUS” on VHF 16) or Sea Tow (800-4-SEATOW, that’s 800-473-2869). With a towing membership the tow is covered; without one, you pay. On a small inland lake with no towing service, call the marina or a friend with a boat, and keep 911 for emergencies.
Anchor if it’s safe, put life jackets on everyone, and let someone know. On the radio, that’s what a PAN-PAN on Channel 16 is for: urgent, but nobody in immediate danger. Then start your tracking link so the people ashore see you drift. If it gets worse, it’s a MAYDAY and 911.
US towing works like roadside assistance: members are towed under their plan, everyone else gets an invoice. Sea Tow puts the average tow at $950. The yearly memberships, side by side:
Prices and coverage from boatus.com/towing and seatow.com/membership, checked 3 Oct 2026. They change, so check the details before you buy. Full side-by-side: Sea Tow vs TowBoatUS.
The app asks you this exact question: is anyone’s life in danger? Yes: it dials 911 and shows you what to say, line by line, with a Mayday form for your VHF. No: it shows TowBoatUS and Sea Tow, each with a Call button for its 24-hour dispatch line, or dials the member number saved in your profile. VesselSOS doesn’t sell towing, isn’t affiliated with either company and isn’t a rescue service. It just puts the right call one tap away.