A neat stack of brown cardboard boxes

Packing tips

How to pack a storage unit (and fit more in)

A well-packed unit can be a size smaller, keeps your things in better condition and saves you from unpacking everything to find one box.

Photo: Kadarius Seegars on Unsplash

Before you start

  • Declutter: don’t pay to store things you don’t want
  • Use strong boxes of two or three standard sizes so they stack well
  • Clean and fully dry everything: damp causes mould
  • Make an inventory, and photograph valuable items for insurance

Packing boxes

  • Heavy items in small boxes, light items in large boxes
  • Fill gaps with paper or soft items so boxes don’t crush
  • Label each box on two sides and the top, with a number that matches your inventory
  • Wrap fragile items individually and mark boxes “Fragile”

Furniture and appliances

  • Dismantle what you can, and keep fixings in labelled bags taped to the item
  • Cover furniture with breathable sheets
  • Defrost and dry fridges and freezers fully, and leave the doors slightly open
  • Store mattresses flat or on their side in a breathable cover

Lay out the unit

  1. Put pallets or boards down so nothing sits on the floor
  2. Place large, rarely needed items at the back
  3. Stack heavy boxes at the bottom and lighter ones on top
  4. Leave a walkway if you’ll need to reach things
  5. Keep the items you’ll need first nearest the door

Get the size right

Packing well can mean a smaller unit. Use our storage unit size guide to estimate, and see how to save money on storage.

Last updated: 13 October 2026

Frequently asked questions

Should I use plastic boxes or cardboard for storage?
Plastic crates protect better against damp and pests and stack well; good-quality cardboard boxes are cheaper and fine for dry, short-term storage. Many people use a mix.
Can I store a mattress in a storage unit?
Yes. Clean and dry it, use a breathable mattress cover and keep it off the floor. Climate control helps for long stays.

What do you need to store?