Why Every Hiker Needs a Dry Bag (And How to Use One)

May 26, 2026

You've been on a hiking trail when it started raining. Your phone got wet. Your spare clothes are damp. Your sleeping bag is questionable. A dry bag costs $17 and prevents all of this. Here's why it belongs in every pack.

What a Dry Bag Actually Does

A roll-top dry bag creates a fully waterproof seal by rolling the opening 3-4 times and clipping the buckle. Unlike ziplock bags (which fail), regular stuff sacks (not waterproof), or backpack rain covers (which leak), a proper dry bag keeps contents bone dry even when submerged.

The 3 Things Always in a Dry Bag

1. Your Phone + Wallet + Documents

Your phone dies if it gets wet. Your ID and cash are irreplaceable on trail. These go in the dry bag first, every time, non-negotiable.

2. Spare Clothes (Especially Tomorrow's Socks)

Dry socks are morale. On a multi-day trek, having guaranteed dry clothes to change into at camp — regardless of what happened during the day — is transformative.

3. Sleeping Bag or Liner

A wet sleeping bag is a camping emergency. Down loses all insulation when wet; synthetic takes hours to dry. Keep your sleep system dry as a non-negotiable rule.

How to Use a Roll-Top Dry Bag Correctly

Load items, leaving 10cm of space at the top
Press air out while closing
Fold the top over 3-4 times (not just once — this is where most people fail)
Clip the side buckle
Test: squeeze the bag — it should feel firm like a balloon

A single fold is not waterproof. Three folds with the buckle clipped is fully sealed.

10L vs 20L: Which Size?

10L: Perfect for valuables + one change of clothes. Fits inside any pack.
20L: Full sleeping bag liner or complete clothing change. Better for multi-day treks.

For most day hikers and weekend campers: 10L is ideal.