How long does it take a mattress to expand?

How long does it take a mattress to expand?


When purchasing a new mattress, one common concern is how long it takes for the mattress to fully expand. The expansion process is crucial as it allows the mattress to reach its intended size and shape, providing optimal comfort and support for a good night’s sleep. In this article, we will delve into the factors that influence the expansion time of a mattress and provide a general idea of how long it typically takes.

Factors Affecting Mattress Expansion Time

Materials used: The type of materials used in a mattress can significantly impact its expansion time. Memory foam mattresses, for example, tend to take longer to expand compared to other types like latex or innerspring mattresses. This is because memory foam mattresses are designed to contour to the body, and the foam needs time to adjust and regain its original shape.

Thickness and density: Thicker and denser mattresses generally take longer to expand compared to thinner and less dense ones. This is because thicker mattresses have more material to expand, and denser foam takes more time to fully decompress and regain its intended shape.

Temperature and humidity: Temperature and humidity levels in the room can also influence the expansion time of a mattress. In colder environments, the materials may take longer to expand, while warmer temperatures can expedite the process. Similarly, high humidity levels can slow down the expansion, while low humidity can speed it up.

Compression and packaging: Mattresses are often compressed and vacuum-sealed for shipping and storage purposes. The amount of compression and the duration of packaging can affect the expansion time. Some mattresses may fully expand within a few hours, while others may take up to 48 hours or more to reach their full size.

Typical Expansion Timeframes

While the exact time it takes for a mattress to expand can vary depending on the factors mentioned above, there are some general guidelines to consider.

For memory foam mattresses, it is common for them to take anywhere from 24 to 48 hours to fully expand. However, some memory foam mattresses may reach their intended size within a few hours, while others may take a bit longer. It is advisable to refer to the manufacturer’s instructions for specific guidance on the expansion time.

Latex mattresses, on the other hand, generally have a quicker expansion time compared to memory foam. They typically expand within a few hours, although it is still recommended to allow up to 24 hours for complete expansion.

Innerspring mattresses, which are constructed with coils and springs, usually do not require much time to expand. They may reach their full size almost immediately after unpacking, although it is still advisable to let them settle for a few hours before using them.

It is worth noting that the initial odor associated with some mattresses, particularly memory foam, may take a few days to dissipate completely. This is a normal occurrence known as off-gassing and is caused by the release of volatile organic compounds (VOCs) trapped in the materials. Proper ventilation can help accelerate the dissipation of the odor.


The time it takes for a mattress to fully expand depends on various factors such as the materials used, thickness and density, temperature and humidity, as well as the compression and packaging. While memory foam mattresses generally take longer to expand compared to other types, latex and innerspring mattresses tend to have quicker expansion times. It is important to follow the manufacturer’s instructions and allow sufficient time for the mattress to expand before using it for optimal comfort and performance.