Self-storage facilities offer a range of unit sizes — from closet-sized 5×5 spaces to garage-sized 10×30 units. Picking the wrong size is one of the most common (and costly) mistakes renters make. Too small and you risk damaging your belongings by cramming them. Too large and you're paying for square footage you don't need. This guide walks you through every standard size, what fits inside each, and how to estimate the right one for your situation.
Standard Unit Sizes at a Glance
| Unit Size | Sq Ft | Best For | Avg Price/mo |
|---|---|---|---|
| 5×5 | 25 | Seasonal items, a few boxes, small closet | $30–$60 |
| 5×10 | 50 | One room of furniture, mattress + boxes | $50–$100 |
| 10×10 | 100 | 1-bedroom apartment or studio | $80–$150 |
| 10×15 | 150 | 2-bedroom apartment | $120–$180 |
| 10×20 | 200 | 2–3 bedroom home, or a standard vehicle | $150–$280 |
| 10×30 | 300 | Large 4+ bedroom home, multiple vehicles | $200–$400+ |
Breaking Down Each Unit Size
5×5 Units (25 sq ft)
Think of a 5×5 as a large walk-in closet. It's the smallest unit most facilities offer and the most affordable — usually $30–$60/month. It's ideal for seasonal decor, a few boxes of documents, small appliances, or a bicycle or two. It won't hold any furniture beyond a small end table.
5×10 Units (50 sq ft)
About the size of a standard walk-in closet. A 5×10 holds the contents of a single bedroom — a mattress, dresser, and 10–15 boxes. It also fits a motorcycle or a kayak with some room to spare. Expect $50–$100/month.
10×10 Units (100 sq ft)
The most popular size — and for good reason. A 10×10 holds everything in a 1-bedroom apartment, including major appliances (washer, dryer, fridge) and a sofa. This is the sweet spot for most renters: $80–$150/month in most markets.
10×15 Units (150 sq ft)
Step up to a 10×15 when you have a 2-bedroom apartment worth of furniture, a king bed, sectional sofa, or multiple large appliances. Typically $120–$180/month.
10×20 Units (200 sq ft)
Roughly the size of a one-car garage. A 10×20 holds a full 2–3 bedroom home's contents, or a 1–2 bedroom home plus a standard vehicle (sedan, SUV). Prices run $150–$280/month depending on market.
10×30 Units (300 sq ft)
The largest standard size — equivalent to a two-car garage. Use it for a large 4–5 bedroom home, multiple vehicles, commercial inventory, or a full office. Less common and available only at larger facilities: $200–$400+/month.
How to Estimate the Right Size
Use this simple method before calling any facility:
- List major items by room. Go room by room and note beds, sofas, tables, and appliances separately from boxes.
- Apply the room-count rule of thumb. One room of furniture → 5×10. Two rooms → 10×10. Three rooms → 10×15. Four or more → 10×20 or larger.
- When in doubt, size up. The price difference between adjacent sizes is usually $20–$40/month. That's far cheaper than renting a moving truck for a second trip because everything didn't fit.
- Account for walkway space. If you plan to access the unit frequently, leave a 2–3 foot aisle down the center. Factor this into your size estimate.
Do You Need Climate Control?
If you're storing electronics, wood furniture, artwork, documents, or clothing, a climate-controlled unit is worth the 25–50% premium. Standard outdoor units experience seasonal temperature swings that damage sensitive materials over time. See our full guide on climate-controlled vs. standard storage to decide if you need it.