Most mattresses begin to sag over time, but there’s a difference between normal body impressions and actual sagging.
Ashley’s warranty policy doesn’t cover body impressions under 0.75″, as these are perfectly normal. Generally, indentations measuring less than 1″ in depth are acceptable and shouldn’t cause discomfort.

However, if these indentations exceed 0.75″ within a 10-year period, you may file a warranty claim.