How long for memory foam mattress to expand?

How long for memory foam mattress to expand?


When purchasing a memory foam mattress, one common question that arises is how long it takes for the mattress to fully expand. Memory foam mattresses are known for their ability to conform to the body, providing excellent support and comfort. However, they typically arrive compressed and rolled up for convenience during shipping. In this article, we will explore the factors that influence the expansion time of a memory foam mattress and provide an estimate of how long it generally takes.

Factors Affecting Memory Foam Mattress Expansion

Materials used: Memory foam mattresses are made from viscoelastic foam, which is a type of polyurethane foam. The specific composition and density of the foam can affect the expansion time. Higher density foams may take longer to fully expand compared to lower density ones.

Temperature and humidity: Memory foam is sensitive to temperature and humidity. Cooler temperatures and higher humidity levels can slow down the expansion process, while warmer temperatures and lower humidity levels can speed it up. It is important to note that extreme temperatures can also have adverse effects on the foam, so it is recommended to let the mattress expand at room temperature.

Thickness and size: Thicker mattresses generally take longer to expand compared to thinner ones. Additionally, larger-sized mattresses may require more time to fully expand due to the increased volume of foam.

Compression time: The duration for which the mattress has been compressed can also impact the expansion time. Mattresses that have been compressed for a longer period may take slightly longer to expand compared to those that have been compressed for a shorter duration.

General Timeframe for Memory Foam Mattress Expansion

While the exact time for a memory foam mattress to fully expand can vary depending on the factors mentioned above, most mattresses typically expand within 24 to 48 hours. However, it is not uncommon for some mattresses to take up to 72 hours or more to reach their full size and shape.

During the initial hours after unboxing, you may notice the mattress expanding rapidly. It is recommended to avoid sleeping on the mattress or placing any bedding on it until it has fully expanded. This allows the foam to evenly distribute and settle into its intended shape.

Tips for Accelerating Memory Foam Mattress Expansion

If you are eager to use your new memory foam mattress and want to speed up the expansion process, here are a few tips that may help:

1. Increase room temperature: Keeping the room slightly warmer can help accelerate the expansion process. However, avoid using direct heat sources as they can damage the foam.

2. Improve ventilation: Good airflow in the room can aid in the expansion of the mattress. Open windows or use a fan to enhance air circulation.

3. Gently massage the mattress: Lightly massaging the mattress can help loosen the foam and promote faster expansion. Be careful not to apply excessive force that could damage the foam.

4. Patience is key: While it may be tempting to rush the process, it is important to exercise patience and allow the mattress to expand naturally. This ensures optimal performance and longevity of the foam.


In conclusion, the time it takes for a memory foam mattress to expand can vary depending on several factors such as the materials used, temperature, humidity, thickness, size, and compression time. While most memory foam mattresses expand within 24 to 48 hours, it is not uncommon for some mattresses to take up to 72 hours or more. By following the recommended tips and allowing the mattress to expand naturally, you can ensure optimal comfort and performance.