If I return my mattress, do I also return the topper? January 29, 2021 19:04 Nope! The complimentary mattress topper will be yours to keep if you decide to return your mattress within the trial period. Related articles What is the Helix Mattress Topper program? How much of a difference will the Mattress Topper make? What items are covered under Helix's return policy? I had to purchase a box to mail my topper back. Can Helix reimburse me? When will I receive my refund?