Storage Unit Size Guide: Pick the Perfect Fit (2026)

Man, I wish someone had sat me down with a cup of coffee and given me this talk before I rented my first storage unit. I ended up with a 10×10 that was so packed, I had to leave my mom’s old armchair behind because it just wouldn’t fit. I still feel bad about that.

The problem with those little size charts online is that they don’t feel real. What does a “5×5” actually look like when you’re staring at a pile of your life’s stuff in the driveway?

Let me break it down for you, not like a robot, but like a friend who’s made the mistakes so you don’t have to.

The “Oh, Is That All?” (The 5×5)

I call this the “closet-plus” unit. If you’re looking at the contents of a single, overstuffed bedroom closet and thinking, “I just need a bit more space,” this is your winner. It will happily swallow:

• That queen mattress and box spring you need to keep for the guest room.
• A dresser (empty it first!).
• A bunch of well-taped boxes full of books, photos, and your old vinyl collection.
• Your holiday decorations—all of them.

If you’re trying to fit your entire studio apartment in here, you’re going to have a panic attack. Trust me.

The “Goldilocks” (The 5×10)

This is, hands down, the most popular size for a reason. It’s just right for so many life situations. It feels like a small bedroom. You can actually walk into it.
This bad boy will hold the contents of a studio or one-bedroom apartment. We’re talking:

• Your couch (unless it’s a massive sectional).
• Your bed frame and mattress.
• A dining table with the chairs stacked on top.
• And still have wall space for a solid pyramid of boxes.

I’ve seen people move out of entire apartments and fit it all neatly in one of these. It’s the workhorse of storage.

The “Family Maze” (The 10×10)

Okay, now we’re talking real space. This is a proper room. If you’re dealing with the contents of a 2-bedroom house, this is where you start looking.
The beauty of this size isn’t just what it holds—it’s that you can access what it holds. You can create a little aisle down the middle. You don’t have to unpack the entire unit to find your kid’s winter coat in November. You can fit couches, multiple dressers, bookshelves, and still have room to breathe.

The “Where Did All This Stuff Come From?” (The 10×15 and 10×20)

These are for the big jobs. The whole-house move. The major renovation. The “I’m inheriting my grandparents’ furniture” life event.
The 10×20 is basically a garage. You could fit a car in there (check with the facility first on rules for that), along with a houseful of furniture. If you’re looking at the pile of stuff and it feels like a mountain, you’re probably in this category.

My No-BS Advice for Picking the Right Size

1. Pile It, Don’t Just List It. This is the golden rule. Don’t just make a mental list. Go into the room and physically group everything you want to store into one corner. Look at the mountain you’ve made. This is the most honest assessment you will ever get.
2. Think Up, Not Just Out. You can stack to the ceiling. A 5×5 might have a small footprint, but if you stack boxes to an 8-foot ceiling, you’d be shocked at how much it holds. Plan to put the heavy, flat stuff (mattresses, table tops) against the wall to build your “walls,” then fill in with boxes.
3. Just Call and Talk to a Human. I’m serious. This is the cheat code. The team at our place, Storage One Hubert, does this all day, every day. We have a spooky ability to hear “I have a three-seater couch, two bookshelves, and about 30 medium boxes” and instantly know what you need.

We can hear the uncertainty in your voice and ask the right questions. “Are the books in small boxes?” (They should be, or they’ll be too heavy). “Do you need to get to your camping gear in October?” (Then we’ll suggest you leave an aisle).

We’re not here to upsell you into a space you don’t need. We’d much rather you be in a perfectly-sized unit and be a happy, long-term customer than be in a huge, expensive one you resent or a tiny, crammed one you can’t use.

So save yourself the Saturday-from-hell I had. Take a good look at your pile, and then give us a ring. Let’s get you the right space from the start.