What Size Dry Bag for Backpacking?

river, getting caught in unexpected downpours while hiking, as well as trying to organize your gear for your next trip. A dry bag is a must have for every backpacker. These bags are capable of keeping your clothes, electronics, and sleeping equipment dry from rain, splashes from the river, or even the sweat accumulating inside the bag.

When it comes to backpacking, having just one bag is far from ideal. Selecting the right number of dry bags is just as, if not more, critical for the safety and efficiency of your gear and equipment on the trail.

Why Dry Bags Matter for Backpacking

Going backpacking usually means coming into contact the with nature’s elements including: traveling rainfall, river crossings, dew in the morning, and you might even break a sweat. Backpacking comes with stressors such as damp sleeping bags and faulty electronics which can capsize your entire trip. Dry bags will shield your essentials, fend off moisture while providing some form of organization with your equipment.

Backpackers seasoned in the art usually tote along several different, appropriately sized dry bags of varying colors just for the purpose of better organization.

Common Uses of Dry Bags in Backpacking

Here’s how dry bags are typically used in backpacking:

• 2–5L Dry Bags: Use to store a headlamp, first-aid kit, phone, wallet, and snacks.

• 10L Dry Bags: Excellent food storage options, along with a lightweight jacket, and cooking utensils.

• 15–20L Dry Bags: Useful for a full change of clothing, insulating layers, or a compact sleeping pad.

• 30L+ Dry Bags: Used for sleeping bags, full clothing kits, or gear needed for longer expeditions or wet conditions.

Using different colored dry bags or labeling them also helps organize your pack—so you won’t accidentally open your food bag when you meant to grab your rain jacket.

Dry Bag Capacity Guide for Backpacking

Here’s a helpful chart to guide your dry bag size choices based on common backpacking needs:

Multi-Bag System vs. One Large Dry Bag

Should you carry one large dry bag or multiple small ones?

Multiple Dry Bags (Recommended):

✅ Easier organization (group by item type)
✅ Less chance of full gear soak if one bag fails
✅ More versatile packing inside your backpack
✅ Quicker access to important items

One Large Dry Bag:

⚠️ May be bulkier and harder to organize
⚠️ All gear at risk if seal fails
⚠️ Less efficient when you only need a few items

For backpacking, a combination of 2–3 dry bags in different sizes (and colors) provides the most efficient, organized, and secure option.

What’s the Best Material for Backpacking Dry Bags?

Every dry bag is different from one another. The material and waterproofing technique are very crucial when selecting a dry bag for backpacking.

✔ Sil-Nylon

• Super lightweight

• Ideal for backpacking where grams matter

• Not fully submersible

• Good for water resistance, not water immersion

✔ TPU (Thermoplastic Polyurethane)

• Thin but durable

• Flexible even in cold weather

• More eco-friendly and abrasion-resistant than PVC

• Great for long-term outdoor use

✔ PVC (Polyvinyl Chloride)

• Heavy-duty, rugged

• Fully waterproof

• Heavier and less flexible

• Better for canoeing, kayaking, but less ideal for long treks

Seam Technology: High-Frequency Welding vs. Stitched & Coated

• High-frequency welded seams: Seamless, 100% waterproof, best for prolonged exposure to wet conditions.

• Stitched + PU coated seams: Lighter, cheaper, but can wear out and let water in over time.

Welded seams dry bags offer the best protection for backpackers who face heavy rain or need to cross rivers.

Backpacking Packing Tips: How to Pack Dry Bags Smart

Efficient packing with dry bags can save time, weight, and frustration on the trail.

• Compress and expel air before sealing to save pack space.

• Place frequently used items (like snacks or rain jacket) in smaller dry bags at the top of your pack.

• Put insulating or fragile gear (like electronics) in the center for better protection.

• Use the bottom layer for bulkier items like sleeping bags or extra clothes.

• For better visibility, use clear or light-colored dry bags inside your dark backpack.

Bonus: Dry Bag Care & Usage Tips

Helpful tips like these can maintain the good condition of your dry bags:

• To ensure a watertight seal, always roll the top 3 times.

• Overstuffing or forcing zippers is not recommended as this puts stress on seams.

• To prevent odor or mold, wet clothes and dry clothes should be stored in separate bags.

• Materials can be weakened by UV light and punctures, so direct sunlight and sharp objects should be avoided.

• To test the waterproof quality of the dry bag, seal it and give a gentle squeeze, watching for any air or water leaks.

• If the bag begins to change textures by becoming stiff or flaky, or discolored, it’s time to replace it.

An appropriate dry bag system dry keeps your gear organized and ready for the trail. For most backpacking trips, a set of multiple dry bags of different sizes that correspond to your gear and the length of your trip is usually best. Look for lightweight and strong materials like TPU or sil-nylon, and focus on seam and seal quality.

Regardless of where the trail leads, keeping your gear dry is one of the easiest ways to ensure comfort and safety when outdoors.