Can You Use a Dry Bag for Swimming?

Yes, a roll-top dry bag works well for swimming, because sealing it with a little air trapped inside makes it float, so it tows along behind you and keeps your phone, keys, and clothes dry while you are in the water. Open-water swimmers use one exactly this way, as a floating carrier for their gear.

Roll a dry bag closed with some air in it and it becomes a buoyant, sealed pouch. Clip the shoulder strap around your waist or hold it, and it drifts behind you as you swim to a sandbar, a mooring, or the far shore. A bright color makes it easy for boaters and lifeguards to spot, which is a quiet bonus of paddling or swimming with one.

It keeps the important stuff dry too. Your phone, car key, wallet, and a dry set of clothes ride sealed inside while you swim, so you are not leaving them on a beach or stuffing them in a jacket. Roll the top down at least three times and clip the buckle for a proper waterproof seal.

One thing to be clear about: a dry bag is not a life jacket. It adds visibility and it floats, but it is not a certified personal flotation device and should never replace one. Wear a proper PFD or a dedicated swim buoy if you need a life-saving device. Use the dry bag for what it is good at, keeping your kit dry and afloat.

The NIXY 10L Waterproof Dry Bag at $26 has a roll-top closure that seals out water and traps air to float, plus an adjustable strap you can tow it by, which is exactly what you want for a swim.

Frequently asked questions

Does a dry bag float when you swim with it? Yes, if you roll it closed with some air sealed inside. That trapped air makes the sealed bag buoyant, so it floats and tows behind you. If you squeeze all the air out before sealing, it will sit lower, so leave a cushion of air in for swimming.

How do you use a dry bag as a swim float? Pack your gear, leave a pocket of air, then roll the top down at least three times and clip the buckle. Loop the shoulder strap around your waist or hold it, and let the bag trail behind you as you swim. A bright color helps others see you on the water.

Is a dry bag a substitute for a life jacket? No. A dry bag floats and adds visibility, but it is not a certified personal flotation device. It should never replace a life jacket or a dedicated swim buoy. Use a proper PFD for safety and the dry bag only to keep your gear dry and afloat.

What size dry bag is best for swimming? A 10L bag is a good all-rounder for a swim, since it holds a phone, keys, and a dry change of clothes without being bulky to tow. Go larger only if you need to carry more, since a bigger bag creates more drag as you swim.