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Setting up a mattress in a box is straightforward, but a few simple steps ensure a smooth expansion and protect your mattress from damage. Here’s everything you need to know from delivery to first sleep.
Before Delivery: Prepare the Room
Clear a path from your front door to your bedroom wide enough for the box (typically 12–15 inches wide). Remove the old mattress before the new one arrives — this is especially important if your bedroom is small. Have scissors or a box cutter ready, but be careful: foam cuts easily and irreparably.
Step 1: Get the Box to the Bedroom First
This is the most important step. A mattress box is much easier to maneuver than a fully expanded mattress. Carry or roll the box to the bedroom, stand it upright, and lean it against the bed frame or wall. Once expanded, a queen mattress weighs 60–100+ lbs and is difficult to move through doorways.
Step 2: Place the Foundation First
Set up your bed frame, platform, or box spring before unboxing the mattress. Mattresses are heavy and awkward to move once expanded. Having the foundation ready means you can unroll the mattress directly into position.
Step 3: Open the Box Carefully
Cut the box open lengthwise with a box cutter — along the bottom edge, not through the top. Tip the box sideways and slide the rolled mattress out. The mattress will be tightly rolled in plastic film. Place the plastic-wrapped roll on the bed frame in the correct orientation (head/foot as desired).
Step 4: Cut the Plastic — Carefully
Use scissors rather than a knife to cut the outer plastic wrap to reduce the risk of cutting the mattress cover. Start at one end and work down the length. The mattress will begin expanding immediately as you cut — this is normal and expected. Stand back slightly as it expands.
Step 5: Remove All Plastic
Pull all plastic wrap from under and around the mattress. Leaving plastic underneath can cause uneven expansion and moisture problems. The mattress will expand rapidly at first, then more slowly over the next several hours.
Step 6: Wait for Full Expansion
Most mattresses reach approximately 90% of their final thickness within a few hours. Full expansion takes 24–72 hours. You can sleep on the mattress the same night, but wait the full 72 hours before judging its feel and firmness. Some initial off-gassing smell is normal — ventilate the room.
Common Questions
Can I sleep on it before it fully expands? Yes, it’s safe to sleep on right away. It just may feel firmer or different than the final result.
What if it doesn’t fully expand? Give it the full 72 hours. If significant areas remain compressed after 72 hours, contact customer support — this occasionally indicates a defect.
My mattress smells. Is that normal? Yes. New foam has a temporary off-gassing smell that dissipates within 24–72 hours. Ventilate the room and it resolves on its own.