Under-bed filament storage has two jobs: the box has to slide under your bed, and it has to keep moisture out. That rules out mesh, fabric and open-top bins. The picks below are low gasket boxes from Sterilite and IRIS USA. Both makers say the lids seal against moisture, and you add the desiccant.

Bambu Lab’s own guidance sets the bar. Its PLA Basic data sheet lists printing and storage humidity as under 20% RH, “sealed with desiccant.” For PETG Basic, it says to place unused filament “in a sealed container with desiccant immediately, and dry thoroughly before printing.”

The Picks in Brief

Pick Outside (L x W x H) Interior at bottom Seal and closure (maker) Best fit
Sterilite 37 Qt. Gasket Box (Amazon search) 24 x 18 x 7 in 19 7/8 x 15 1/8 x 5 5/8 in Gasket seal and tight-fitting latches Most beds with 7 in or more of clearance
IRIS USA WeatherPro 41 QT Gasket Box (4-pack on Amazon) 23.60 x 17.75 x 7.88 in Not published Seals in the lid; multi-buckle latches More room per box, if the bed clears 7.88 in
IRIS USA WeatherPro 30 QT Gasket Box (Amazon search) 19.70 x 15.75 x 7.75 in Not published Seals in the lid; 4 buckle latches Smaller footprint
Sterilite 12 Qt. Gasket Box (Amazon search) 16 1/8 x 11 1/4 x 6 3/4 in 12 1/2 x 9 x 5 1/2 in Gasket seal and tight-fitting latches Tight clearance, one material per box

None of these boxes has wheels. Sterilite’s wheeled 60 Qt. under-bed box and IRIS USA’s 40 qt. under-bed box have latching lids, but their makers list no gasket or seal, so they missed the cut (see below).

Step 1: Measure the bed clearance

Measure from the floor to the lowest point under the bed, not to the mattress. Check the side rails, the center support and any slats or legs that hang below the frame. On carpet, measure with the pile pressed down where the box will sit. Then compare that number with the box’s outside height, and leave a little extra so the lid and latches don’t scrape on the way in.

As a guide: the Sterilite 12 Qt. box needs more than 6 3/4 inches, the Sterilite 37 Qt. box more than 7 inches, and the IRIS boxes more than 7.75 or 7.88 inches.

Step 2: Check spool fit against the interior

Spool sizes vary by brand, so measure the diameter and width of the spools you buy. Lay them flat and compare with the box’s interior dimensions. Sterilite publishes interior dimensions at the bottom of each box, which is the measurement that matters for flat spools. IRIS publishes only outside dimensions, so allow for wall thickness and the taper of the sides.

Leave room for the desiccant and, if you use one, a small hygrometer so you can see when the desiccant needs replacing.

Step 3: Seal it, and add desiccant

A gasket keeps outside air from leaking in, but the box doesn’t dry anything. Put fresh or recharged desiccant inside with the spools, keep spools in their bags if you like, and close every latch. Filament that is already damp still needs drying before printing.

1. Sterilite 37 Qt. Gasket Box: Best Overall

This is the one box here that its maker describes as fitting under a bed: Sterilite says the 37-quart container “fits neatly under bed.” Its outside dimensions are 24 x 18 x 7 inches, and the interior at the bottom is 19 7/8 x 15 1/8 x 5 5/8 inches. Sterilite says the gasket seal and tight-fitting latches keep the lid secured to the base, and that the gasket line’s lid seal is there “to safeguard against air and moisture.” The base and lid are clear, so you can see colors without opening the box.

Sterilite also notes that the 37 Qt. and 80 Qt. boxes share a lid size, so they stack in the same footprint if you later move some stock to a shelf.

Choose it if your bed clears 7 inches. It is the best balance here of low height, published interior space and a documented under-bed fit.

Sterilite’s product page

2. IRIS USA WeatherPro 41 QT Gasket Box: More Room, a Little Taller

IRIS’s 41 QT WeatherPro box is 23.60 x 17.75 x 7.88 inches outside. IRIS says its WeatherPro bins have “high quality heavy duty seals in the lids to block out moisture and dust,” and that multiple buckle latches lock onto the lid. IRIS sells it singly or in a 4-pack. The Amazon link here is the 4-pack sold by Amazon.com.

IRIS doesn’t include this box in its under-bed storage range, and it doesn’t publish interior dimensions. It earns a place because its listed height is under 8 inches. Measure your clearance against 7.88 inches before ordering.

IRIS USA’s product page

3. IRIS USA WeatherPro 30 QT Gasket Box: Smaller Footprint

The 30 QT WeatherPro box is 19.70 x 15.75 x 7.75 inches outside, with the same lid seals and four buckle latches. Its smaller footprint suits a narrow gap between bed legs, or splitting materials so you open fewer spools at once. As with the 41 QT box, IRIS publishes no interior dimensions or under-bed claim.

IRIS USA’s product page

4. Sterilite 12 Qt. Gasket Box: For the Tightest Clearance

At 6 3/4 inches tall, this is the lowest sealed box here. Outside it measures 16 1/8 x 11 1/4 x 6 3/4 inches, and the interior at the bottom is 12 1/2 x 9 x 5 1/2 inches. It has the same gasket seal and latches as the 37 Qt. box.

The small interior means few spools per box, so it works best for one material or a few open spools, with several boxes side by side. Check your spool diameter against the 9-inch interior width before buying.

Sterilite’s product page

What Missed the Cut

  • Sterilite 60 Qt. ClearView Latch Wheeled Underbed Box: made for under-bed use, with wheels and a 7-inch height. Sterilite describes latches that keep the lid secure, but no gasket or seal, so it isn’t a sealed filament box.
  • IRIS USA Under Bed Storage Box, 40 qt.: IRIS says it is designed to fit under most beds, and it is 6.3 inches tall with published inside dimensions of 25.2 x 15.2 x 5.7 inches. IRIS describes durable latches that secure the lid, but no gasket or seal.
  • Mesh or fabric under-bed bags: designed to let air through, which is the opposite of what stored filament needs.
  • Filament dry boxes: built for feeding a printer, not for long-term storage under a bed.

Who Should Look Elsewhere

If filament moves between the printer and a dryer every day, keep it near the printer in a dry box instead. Under-bed storage suits backup spools you open every few weeks. And if your bed sits lower than 6 3/4 inches, none of these boxes fits; use a closet shelf with the same sealed-box-plus-desiccant setup.

Final Recommendation

Start with the Sterilite 37 Qt. Gasket Box if your bed clears 7 inches. Choose the IRIS WeatherPro 41 QT for a little more space per box if you have just under 8 inches, the IRIS WeatherPro 30 QT for a smaller footprint, and the Sterilite 12 Qt. when clearance is tightest. Whichever you choose, add desiccant and close every latch.

Sources

Checked October 5, 2026:

Frequently Asked Questions

Is a sealed box necessary for filament under the bed?

For spools you are storing rather than printing from, yes. Bambu Lab lists storage humidity for its PLA Basic as under 20% RH, sealed with desiccant, and tells PETG Basic buyers to put unused filament in a sealed container with desiccant. A gasket box with desiccant inside fits that advice. A mesh or open bin does not.

How much bed clearance do I need?

More than the box’s outside height. Measure from the floor to the lowest point of the bed frame, including side rails and center supports, then subtract carpet and leave a little room to slide the box. The lowest box here, the Sterilite 12 Qt. Gasket Box, is 6 3/4 inches tall; the others are 7 to 7.88 inches.

How many spools fit in each box?

It depends on your spools. Measure the diameter and width of the spools you buy and compare them with the box’s interior dimensions. Sterilite publishes interior dimensions at the bottom of each box. IRIS lists only outside dimensions, so allow for wall thickness and taper.

Do I still need to dry filament stored in a sealed box?

A sealed box slows moisture pickup, but it doesn’t dry filament that is already wet. Bambu Lab tells PETG Basic users to dry it thoroughly before printing.