Our CNET Sleep editors have tested more beds than the average sleeper -- around 300 different ones, in fact -- and have dedicated hundreds of hours to the craft. We take pride in our mattress testing methodology.

The main consideration we take into account when we look for the best mattress for side sleepers is firmness and the amount of pressure relief a mattress offers. When testing mattresses, we lay in each sleeping position (including side) and determine how well they accommodate our primary pressure points. When we're on our side, it's crucial our hips and joints feel properly cradled. If a bed's too firm, it can press into your pressure points and cause soreness or pain.

It's important to note that firmness is subjective and varies from person to person. So, CNET has created a tool to objectively test a mattress’s firmness. Our proprietary machine, properly named the Mattress Smasher 9000, presses into the middle of a bed, and our corresponding software measures firmness on a scale of 1 to 10, with 1 being the softest and 10 being the firmest. We would never recommend a mattress with a high firmness score to side sleepers. 

Here are the objective firmness levels we gathered testing the best mattresses for side sleepers with our Mattress Smasher 9000, sorted from the softest to the firmest.

Other key factors we test are edge support, motion isolation and temperature. Edge support is how strong the bed’s perimeter is, which is important if you sleep with another person or hug the edge of the bed. Motion isolation is how well a mattress dampens movement across the surface. We test this by having two testers roll around and bounce on the bed.

CNET editors pick the products and services we write about based on editorial merit. When you buy through our links, we may get a commission. Read more on how we test mattresses.