How to Pick the Right Size Storage Unit

Written by: Editorial Team - Published: May 18, 2024


When getting ready to move or after a significant life change — getting married, perhaps — a storage unit can be a great place to put items you don't want to get rid of but don't have space for. Unless you've moved recently or handle moving professionally, you may not know how much space you need. In your house, you lay items out to fill the space. In a storage unit, you pack things together as tightly as possible. You don't want to get a unit that has a lot of wasted space since you pay for every square foot. At the same time, a storage unit that's too small means transporting some items back home, where you still don't have room for them. Here are a few tips to help determine which size of storage unit you need.

Key Points

  • 1 Inventory the items you plan to store. You need to know what you have going into storage to determine the size of the unit you need.
  • 2 Use your moving truck to help with size estimates. Most trucks are 8 feet tall, which is the standard ceiling height at a storage facility.
  • 3 Unless you’re only using a storage unit in preparation for an upcoming move, be sure to leave enough room to maneuver and access your items. Packing and unpacking a unit to get to a single box is no fun.
  • 4 Always go bigger. Having too much space is a lot less of a hassle than having too little.

Create a Storage List

The first step to choosing a storage unit is deciding what needs to go into storage. A detailed list of everything that’s leaving lets you better estimate the amount of floor space you need. If you’re storing a lot of furniture, measure each item’s footprint. With the measurements in hand, you can figure out the minimum square footage required for your most substantial items. Add in the boxes, and you can make a reasonable estimate. Just don’t forget that some items may stack on top of each other. For example, a pair of end tables often stack neatly with one table face down on top of the other. The moving truck you use can be an excellent way to gauge the size you need. Many storage units are sized similarly to moving trucks.

Will You Need to Access Your Stuff?

How you intend to pack your unit may also impact the size you need. If storing items is short-term, pending a planned move, you can fill in every cubic inch of space, right up to the ceiling. You won’t need to build in an aisle or worry about getting a specific box out of storage. When you’re looking at a storage unit as a long-term solution, you might need to go in and move things around more regularly. In that case, you’ll want to have enough room to maneuver, pull boxes down and reorganize to find seasonal items or grab a piece of furniture to replace a broken item at home. If you need access to your things in storage, you need a much bigger unit.

Think in Three Dimensions

When shopping for a storage unit, the length and width of the space are essential, but so is the height. Most storage units offer an 8-foot ceiling, but a taller one might mean a lot more space. After all, you can stack right up to the roof when you pack the room. Lower ceilings may mean substantially less space. When asking about a unit, be sure to ask for all of the dimensions so that you don’t run into any unpleasant surprises.

Always Round Up

Once you have a solid estimate of the amount of space you need, round up to the next size. There’s nothing more irritating and frustrating than getting your stuff half moved in and realizing there isn’t enough space for the rest of your things. If you do get a unit that’s too small, you might spend all day moving things in and out to try and squeeze in the last few boxes. If it won’t all fit, you might need to upgrade your unit and move everything again. That’s a lot of unnecessary work. And your storage facility may not have anything available in a larger size. If you can afford to upsize from your estimate, do it.

Understanding Storage Unit Sizing

It can be difficult to visualize the amount of space you need in a storage unit. If you’re using a moving truck, a good rule of thumb is that you need a storage unit that is one size down from the truck. For example, if everything fits into a 25-foot truck, you likely only need a 10’x20′ storage unit. With a 15-foot truck, you can opt for a 10’x10′ option.

Units may be available as small as 4’x 4′, but that is the size of a large closet. You might fit a few items of furniture inside or stack in some boxes, but don’t expect to pack in an entire room from your home. These compact units are often great for seasonal storage like holiday decorations or camping gear. Larger units usually come in the following sizes.



Estimated Content


50 square feet

Expect to fit the contents of a one-bedroom apartment, including a queen-sized mattress, dresser, sofa and totes or boxes.


100 square feet

Imagine what you could fit into an extra bedroom, particularly if you aren’t worried about floor space, and you’ll have a good idea about what 10’x10′ can hold. Generally, this unit can hold two bedrooms worth of stuff or an entire living room full of furniture, including the couch, chairs, coffee table, TV and bookshelves.


150 square feet

At 150 square feet, this storage unit is the equivalent of a one-car garage. Typically, you could fit three bedrooms’ worth of furniture and boxes into this unit. You might also use something this size to store large appliances such as a fridge or other big furniture items such as a piano or big-screen TV.


200 square feet

You can pack an entire three-bedroom apartment into one of these units. That includes everything from the couches and bedroom sets to the dining room table and refrigerator. It might also be a good place to store a classic car if you need a winter shelter. Just make sure the unit has outdoor access if you’re using it as a garage.


300 square feet

At many facilities, this is the largest unit size, and it can store pretty much anything. Whether you need a place to put your boat or have a five-bedroom house, this storage unit has enough space to get everything in.

Your ability to pack items into the space impacts how much you can fit into a storage unit. The better you are at packing, the more you can fit comfortably into the unit. Just remember to leave enough space to move around if you need access to anything you’ve put into storage.


Should I go bigger or get two units?

It’s typically less expensive to rent a larger unit than to rent an additional small unit. Unless there’s a reason to separate your items (some might need climate control), going bigger is better.

Do I need climate control?

If the items you need to store can stand up to temperature fluctuations and changes to the humidity level, you likely don’t need climate control. Protection from the elements is enough.

When should I ask for outdoor access?

If you plan to store items that don’t fit through standard doorways, a garage door opening to the outside can make it possible to get things in and out.

Can I downgrade if I don’t need as much space?

As long as the facility has a smaller space available, you can likely switch. Be sure to check your rental terms and be ready to pay for the overlap during your moving month. If you need both for a few days, you may pay for an extra month to get the lower long-term rate.