Mattress Topper & Underlay Sizes Australia (Size Chart in cm)

Australian mattress topper and underlay sizes in cm: Single 91 x 188, Double 137 x 188, Queen 152 x 203 and King 183 x 203. A topper or underlay is cut to the mattress size so it sits flat under the fitted sheet; buy the size that matches your mattress.

Choosing the right topper size and depth

Match the topper to the mattress size in the chart; a topper is not oversized because any overhang would fold down the mattress edge and shift under the sheet. Depth is the other decision. A thicker memory foam topper changes the feel of a firm mattress the most, while a slimmer quilted topper or foam underlay adds softness and protects the mattress without a big change in height. Read the Mattress Topper Buying Guide and the Mattress Underlay Buying Guide for the differences between memory foam, wool and cotton fills.

Will my sheets and protector still fit over a topper?

Usually, yes. Tontine mattress protectors and standard fitted sheets have a 40 cm skirt, which reaches around a normal mattress plus a topper. If your mattress is already very deep, measure the combined depth of mattress and topper before buying sheets. The layering order is mattress, topper, protector, then fitted sheet, so the protector keeps the topper clean.