Expansion times get quoted confidently all over the internet, usually with one brand's number applied to every mattress. They are not the same. Below is what each brand states on its own website — support articles, setup pages and unboxing instructions — with nothing filled in from third-party sources. Where a brand has not published a figure, this guide says not published rather than estimating one. Where a brand publishes two different numbers on two of its own pages, that is noted too, because it happens more than you would expect.
NECTAR. Expansion: 24–72 hours. Sleeping on it: Nectar's own pages disagree — one says you can sleep on it right away, another recommends waiting a day or two. Boxed storage limit: not published. DREAMCLOUD. Expansion: up to 72 hours to reach full height. Sleeping on it: DreamCloud's setup page says you can sleep on it after a few hours of expansion. Boxed storage limit: not published.
CASPER. Expansion: up to 72 hours to reach maximum dimensions, and Casper notes its Snow and Snow Max models may take longer. Sleeping on it: yes — Casper's support article says you can start sleeping on it right away once the sheets are on. Boxed storage limit: not published. TUFT & NEEDLE. Expansion: 48–72 hours to full dimensions, with a recommendation to let it air and expand 2–3 hours after unboxing for the best feel. Sleeping on it: yes, and Tuft & Needle states that sleeping on it does not affect expansion. Boxed storage limit: set up within 3–4 weeks; the brand warns that longer than four weeks compressed could damage the mattress.
BROOKLYN BEDDING. Expansion: up to 24 hours. Sleeping on it: no explicit same-night statement published. Boxed storage limit: unroll within 30 days of delivery, because longer compression can affect its ability to expand fully. AVOCADO. Expansion: Avocado publishes two figures on two pages — allow 3–5 hours on its help centre, and give it a day to fully expand on its unboxing page. Sleeping on it: yes — Avocado says you can rest on it immediately while it finishes expanding. Boxed storage limit: open within 30 days.
BEAR. Expansion: Bear also publishes two figures — 24–48 hours to decompress on one support page, and full expansion within 72 hours with some settling over the first few days on another. Sleeping on it: Bear frames it as good to sleep on once fully expanded, rather than immediately. Boxed storage limit: unbox within 30 days, and Bear specifies hybrids are best unwrapped within three weeks while all-foam models like the Original are best unwrapped within 30 days. NOLAH. Expansion: no numeric figure published. Sleeping on it: yes — Nolah says you can sleep in the bed the day it arrives. Boxed storage limit: unbox within a few days, and within 30 days at the latest.
LEESA. Expansion: no numeric figure published on its setup pages. Sleeping on it: not published. Boxed storage limit: open within 30 days; Leesa says longer is safe for the mattress but may prevent it decompressing fully. ZINUS. Expansion: 48–72 hours to return to its original shape. Sleeping on it: Zinus publishes a myth-busting article rejecting the idea that you cannot sleep on it right away, but we could not retrieve its exact wording, so treat this as directional. Boxed storage limit: not published.
PURPLE, HELIX, WINKBED, LUCID AND SIENA. Purple maintains dedicated support pages on both when you can sleep on it and how long it can stay rolled up, but the pages sit behind bot protection and the figures could not be read, so nothing is quoted here. Helix publishes per-model setup instructions that are largely video-based, with no numeric expansion time located. WinkBed publishes unboxing steps but no expansion time, sleep-tonight statement or boxed storage limit. Lucid publishes a 24–48 hour expansion window for its toppers, but not for its mattresses. Siena's guide page could not be read. For all five, check the instruction card that shipped in the box or contact the brand.
HOW TO READ THESE NUMBERS. Three patterns stand out. First, the outer figure is usually 72 hours and the practical figure is much shorter — most mattresses are close to full loft within a few hours. Second, boxed storage limits cluster tightly at 30 days across the brands that publish one, which is a useful default when your own brand is silent. Third, expansion is temperature-dependent: every one of these figures assumes a normally warm room, and a cold bedroom will slow the process noticeably.
WHAT SLOWS EXPANSION DOWN. A cold room, a mattress that spent time in a freezing delivery van or garage, and a long time compressed in the box. If a mattress looks under-inflated after a few hours, warm the room, leave it uncovered with nothing on it, and give it the full window the brand publishes before you contact anyone. Verified against each brand's own published setup and support pages, September 2026.