If your mattress has physical signs of deterioration, that means that it’s time for a change. How those changes manifest depends on the type of mattress you have. If you’re rolling with an inner coil mattress, maybe there are some lumps from where the springs have lost tension. If you’re using a hybrid mattress, look for fraying along the stitching or for spots where the different materials may come undone.

Often if it’s reached this level of degradation, you’ve been sleeping on a bad mattress for a while. You probably already know how often to change a mattress, so trust your gut before it gets to this point! It’s your body that’s at stake.

This one depends on the type of mattress you have. Often, innerspring mattresses are only good for about six or seven years — even if they say that their lifespan is ten or more. That's simple science. A coil loses its tension after a preset period. Once it's uncoiled, there's not a whole lot more you can do to prolong the mattress. A few things can help (more on that in a minute), but overall, how often to change a mattress is decided the moment you buy it.

Some newer materials and mattresses do last longer. Memory foam and hybrid mattresses are a great way to get good value for the price you're paying. Memory foam is super-durable and has the benefit of not using a coil system, so there's no mechanical process to break down. That means these beds can last not only years but decades. That's not to say that things don't go wrong (this is the real world, after all), but many of these mattresses are backed by lifelong warranties that prove the bed's lifespan is no fluke.

Take the Nectar mattress, which offers a Forever warranty, to indicate how long some foam mattresses can last without replacement.