If I return my mattress, do I also return the complimentary topper? April 28, 2021 15:06 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 Birch Mattress Topper program? Will I be charged for the complimentary mattress topper if I return my Birch? Who is eligible for a complimentary mattress topper? How much of a difference will the complimentary Mattress Topper make? What is the Birch return policy?