Short answer
It depends on the brand, so check yours. Purple recommends unrolling within two weeks of delivery. Nectar says to open it as soon as it's delivered and treats boxes left closed for 90 days as misuse. Casper recommends opening within the first 100 nights. Once it's out, let it expand on a breathable base.
Book your mattress cleaning
Regular price $249, Fall 2026 promotion price $199first mattress, any size · Fall 2026 promotion
HEPA vacuuming, enzyme treatment for organic odor, dry vapor steam and UV-C. We recommend cleaning twice a year.
Brand by brand
- Purple: "We recommend you unroll the Purple® Mattress within two weeks of delivery" (Purple).
- Nectar: open it when it arrives. Mattresses not opened within 90 days of delivery "are considered misused and are ineligible for warranty claims and returns" (Nectar).
- Casper: open it within the first 100 nights to use the trial. Casper says it has no evidence that longer boxing damages the mattress, but it may take longer to expand (Casper).
After unboxing
Set it on a breathable base, not damp concrete (is it bad to put a mattress on the floor). Any new-foam smell is covered in off-gassing.
Where to read next
How we clean what you can't see
This section is our view. Every Sleep Sanitation visit starts with a nose-and-eyes inspection to find where the odor actually lives, then HEPA vacuuming, enzyme treatment on organic odor, low-moisture dry vapor steam from our Italian-made Vapor Clean machines, UV-C light treatment and a moisture check before we leave. Underside treatment, for the side that faces the floor or frame, is +$50–$75 per mattress. The first mattress is $199 Fall 2026 special (regularly $249), any size. We recommend cleaning every mattress twice a year. Take the 60-second mattress quiz or schedule your cleaning. Call or text (402) 512-5658, or email info@sleepsanitation.com.
Changelog
- 24 October 2026: First published. Sources accessed on this date.
Sources
- How long can the Purple Mattress stay rolled up in its packaging? · Purple
- How Long Does a Nectar Mattress Take to Expand? · Nectar
- Frequently Asked Questions · Casper
Last reviewed October 24, 2026. Manufacturer specifications and care instructions change; check the current version for your exact model. This page is general information, not medical advice. How we source and check pages: editorial standards.