While the lifespan of a mattress depends upon several factors, even the highest quality mattress under the best care wears out eventually, no matter what it is made from. A mattress needs to be replaced in eight to 10 years on average, but under some conditions may need to be replaced even sooner.
Time to Replace
If the mattress feels so uncomfortable that you feel tired even after sleep, the mattress may need to be replaced -- especially if the same mattress once felt comfortable. Springs poking you as you rest, or tears in the mattress itself are signs the mattress should be replaced. If the mattress sags uncomfortably, offering little support, it needs to be replaced. Memory foam and latex foam mattresses behave differently since their structure is entirely different. These mattresses may last 10 to 20 years, depending on the quality of construction and the frequency of use. If your mattress of any type still feels completely comfortable to you even if it is beyond the average mattress lifespan, you may be able to hold off on purchasing a new one a bit longer.