Storage Unit Sizes Explained: From 5×5 to 10×30

Storage unit sizes are deceptively simple to look at and consistently overestimated by renters. The marketing photos always show a tidily packed unit with everything visible and accessible; the reality is that you stack, you forget, and you run out of room two boxes before you finish. This guide gives realistic capacity estimates for each common size, plus the specialty equivalents you will see for vehicles and oversized goods.

5×5 (25 sq ft)

Roughly the size of a closet. Holds 10-15 banker boxes, a few small chairs, seasonal items, and not much else. Useful for personal records, holiday decorations, and overflow from a small apartment. Typical price: $45-95/month depending on metro and climate.

5×10 (50 sq ft)

Roughly half a single-car garage. Holds the contents of a studio or one-bedroom apartment if you are disciplined: a queen mattress and frame, a small sofa or loveseat, a desk, a few chairs, and 20-30 boxes. Useful for college students between school years, or short-term moves. Typical price: $75-145/month.

10×10 (100 sq ft)

A single-car garage equivalent. Holds the contents of a small one-bedroom or large studio: bed, sofa, dining set, bookshelves, dressers, kitchen items, and 30-50 boxes. Comfortable margin for two-bedroom apartment contents if you stack and pack well. Typical price: $120-240/month.

10×15 (150 sq ft)

Comfortably fits two-bedroom apartment or small two-bedroom house contents. A king bed, full living room, dining set, multiple bookshelves, and ample box space. Also a common size for small-business inventory or estate consolidation. Typical price: $170-320/month.

10×20 (200 sq ft)

Three-bedroom house contents, or a single car plus boxes. The standard size for full-house storage during a longer move or renovation. Also fits most non-extended-bed pickup trucks. Typical price: $220-410/month.

10×30 (300 sq ft)

Four-bedroom house contents, or a vehicle plus furnishings, or a small business inventory + records combination. Also the entry size for some boat and RV storage that does not require a dedicated bay. Typical price: $310-560/month.

Specialty and oversized

• RV bays: typically 12×30 to 14×50, sized for Class A motorhomes with slides.
• Boat bays: 12×30 to 14×40, with door heights of 14 feet for raised wakeboard towers.
• Wine vaults: case-lot sizes (typically 25-200 cases per locker) rather than square footage.
• Document storage: priced per box or per linear foot of shelving rather than per unit.
• Fine art: priced per piece or per cubic foot, often with handling and viewing room access included.

How to size your unit

A good rule of thumb is to estimate the size you think you need, then go up one size. The marginal cost is small, the marginal access value is large, and the cost of moving units mid-lease is significant. If you have any uncertainty about volume — you have not packed yet, you have an attic full of mystery boxes, or the contents include large oddly-shaped pieces — bias toward the larger unit.