Short answer: if you swim in open water without a kayaker or boat alongside you, a tow float is the single cheapest piece of safety kit you can carry. It will not keep you alive on its own — it is not a lifejacket — but it makes you dramatically easier to see, gives you something to rest a hand on while you catch your breath, and carries your kit while you swim.
- A tow float makes you visible to boats, paddlers and spotters — visibility is the biggest single safety factor in open water.
- It is not a flotation device. It will not support your body weight and is no substitute for supervision or judgement.
- Most open-water venues in the UK and many organised US swims now require one.
- A dry-bag style float carries phone, keys and layers — useful for point-to-point swims and cold-water dips.
- Cost: roughly £25–£40 / $30–$50. There is no cheaper way to be seen.
What does a tow float actually do?
Three jobs. First, visibility: a high-visibility buoy sits on the surface behind you where a low swimmer's head disappears between waves. Boat traffic, kayakers, race safety crews and shore spotters pick out the float long before they pick out a head in dark goggles. The RNLI's open-water guidance and the American Red Cross both make the same point about open water: being seen is the first layer of safety.
Second, rest: you can put a hand on the float and tread water while you sort your goggles, sight the next buoy or catch your breath. It is buoyant enough to steady you — but it is not designed to support a swimmer's full body weight, and no reputable manufacturer claims otherwise.
Third, with a dry-bag design, storage: phone, car key, a thin layer for after. That turns point-to-point swims and remote-water dips from a logistics problem into a swim.
When do you genuinely need one?
- Swimming alone or unsupported. No kayak escort, no lifeguarded beach — the float is your visibility. (Swimming truly alone is never recommended; the float does not change that.)
- Cold-water season. In water below 60°F / 15°C, incidents escalate faster and rescuers have less time to find you. Cold-water swimmers should treat a float as standard kit, alongside acclimatisation and a swim partner.
- Organised venues and events. Most UK open-water venues require a tow float for entry; many US open-water swims and triathlon training venues have followed. Check the rules before you travel.
- Boat traffic. Lakes, lochs, reservoirs and coastal water shared with craft — this is exactly the situation the float exists for.
When is a tow float not enough?
A float does not fix bad judgement. It does not warm the water, read the tide, or replace a lifejacket for anyone who cannot swim strongly. US Masters Swimming's open-water guidance and the Outdoor Swimming Society's advice agree on the fundamentals: know the venue, check conditions, acclimatise to cold water gradually, and swim where someone can reach you. The float is the last layer of visibility on top of those decisions, not a substitute for them.
Buy the float for the day everything else goes wrong — a cramp, a fog bank, a current — when being findable is what matters.
What should you look for in a tow float?
- High-visibility colour — fluorescent orange, yellow or pink. Reflective panels help in low light.
- Dual chambers — an air chamber for buoyancy plus a separate roll-top dry compartment, so a puncture never takes both.
- 15L / 4 US gal capacity if you want it to carry kit; smaller if you only want the marker.
- An adjustable waist leash that tows flat behind you without dragging your hips.
- CE / UKCA marking and honest labelling — walk away from anything sold as a "rescue" device.
CAIRN
Hi-vis tow float and 15L dry bag in one — dual chambers, built-in whistle, reflective panels, CE / UKCA certified. Built for cold water and all conditions.
Does towing a float slow you down?
Marginally, and less than most swimmers expect. A well-shaped float on a properly adjusted leash sits in the water your body has already disturbed. Triathletes train with them for exactly this reason: the drag penalty is small and the safety margin is not.
FAQ
No. A tow float is a visibility and dry-storage aid that trails behind you on a waist leash. It is not a personal flotation device and must never be relied on to support a swimmer's body weight.
Most managed open-water venues in the UK require one for entry, and many organised swims and triathlon training venues in the US have adopted the same rule. Check the venue's rules before you travel.
Only marginally. A well-shaped float on a properly adjusted leash tows in the water your body has already disturbed, so the drag penalty is small — triathletes train with them routinely.
If you want it to carry kit, a 15-litre dry-bag style float holds a phone, keys and a dry layer. If you only want the visibility marker, smaller floats work — but the dry-bag style does both jobs.