Sheets that fit: pocket depth, split sizes and what the fabric changes

Most sheet complaints we hear in the store are about fit, not fabric. The fitted sheet pops off a corner at 2 AM, or bunches under your hip, because it was bought for the wrong mattress height or size. This guide covers the measuring first, then the fabric, so you buy once.

Know this before you start: under our refund policy, bedding, pillows and accessories are final sale once opened, and the 120-night comfort exchange is for mattresses only. Measure before you buy, and keep the package sealed until you are sure.

Measure your mattress first

Two numbers decide whether a fitted sheet stays on: the mattress size and the mattress height. Most people guess the second.

Height, with everything on

Measure the side of the mattress from the bottom edge to the top surface, with the protector on and, if you use one, the topper on too. Round up to the next inch, then add about two inches so the elastic can tuck underneath.

Standard pocket or deep pocket

The pocket is the depth of the fitted sheet's corner. Each listing states a depth range, and your height plus the tuck must sit inside it. Tall mattress, pillow top or topper: look for deep pocket. Malouf describes its Rayon from Bamboo sheets as fitting mattress depths of 6 to 22 inches and its Brushed Microfiber sheets as fitting 6 to 18 inches. Purple's SoftStretch sheet set comes in a Standard fit and a Deep Pocket fit for taller mattresses.

Sizes in inches

King is 76 by 80 inches. California king is 72 by 84, four inches narrower and four inches longer, so a king fitted sheet runs loose and short on it. Some stretch knits list a combined King/Cal King size cut to cover both.

Split king and split California king sheets

A split king is two twin XL mattresses side by side, usually on two adjustable bases so each side moves on its own. Because the halves move separately, a split king set is two twin XL fitted sheets, one king flat sheet and two king pillowcases.

A split California king has two narrower, longer halves. Twin XL fitted sheets are 4 inches too short for it, so buy a set labeled split California king. Malouf's Classic Cotton, Woven Supima, Rayon from Bamboo and Brushed Microfiber split sheets come in both split sizes, as do Tempur-Pedic sheets; Purple SoftStretch comes in split king in the Deep Pocket fit. On an adjustable base, measure with the base flat and favor strong elastic or stretch, since corners pull when the head goes up. Our split king guide and adjustable base guide cover the rest.

Fabrics compared

With the fit settled, the fabric decides how the bed feels and how it washes. Thread count comes up in every conversation, and it is not the whole story. Fiber and weave matter more: a modest count in long-staple cotton can outlast a high count in a coarse fiber.

Cotton. Percale is a one-over-one-under weave, which is why it feels crisp and airy; Malouf describes its Classic Cotton set as an open percale weave with a crisp, refreshing feel. Sateen floats the yarn for a smoother surface with a soft sheen; Malouf describes its Woven Supima sheets as 100 percent American-grown extra-long staple cotton in a sateen weave, with extra-deep pockets for thicker and pillow top mattresses. Tempur-Pedic's Classic Cotton set is a long-staple cotton whose fitted sheet the brand describes as four-way stretch.

Rayon from bamboo. A rayon fiber made from bamboo pulp. Malouf describes its Rayon from Bamboo sheets as silky soft, moisture wicking and breathable.

Brushed microfiber. A fine polyester with a brushed surface, which Malouf describes on its Brushed Microfiber sheets as super soft and stain and wrinkle resistant. The easiest to care for, and the warmest of the group.

Stretch knit. Knits stretch every way, so the fitted sheet follows an adjustable base without pulling at the corners. Purple describes its SoftStretch sheet set as a soft, stretchy blend of rayon from bamboo, polyester and spandex. Tempur-Pedic describes its Breeze cooling sheet set as a knit made with Tencel lyocell fibers and cooling nylon, cool to the touch.

If you sleep hot

Start with a crisp cotton percale or a rayon from bamboo sheet. Both move air and moisture better than a heavy brushed fabric, and percale feels cool when you first get in. Skip brushed microfiber in summer; what makes it cozy in January holds warmth in August. A plastic-feeling protector under the sheet traps heat whatever is on top. See our protectors and, for the mattress side of the problem, our guide to sleeping hot in Los Angeles.

Pillowcases and sizes

Pillowcases come in standard and king. Standard cases fit standard and most queen pillows, and some brands label that size queen. King cases are longer, for king pillows; a king pillow in a standard case hangs out the open end. King and California king sets come with king cases. For extras, Malouf's Supima pillowcases and Purple's SoftStretch pillowcases are sold on their own in both sizes. Match the case to the pillow, not the bed; see our pillows too.

Care

The label wins, but these habits hold across every fabric we sell:

• Wash new sheets before the first night to remove finishing residue.
• Use cold or warm water, not hot. Hot water shrinks cotton and tires out elastic.
• Tumble dry on low; take sheets out slightly damp for fewer wrinkles.
• Skip fabric softener and dryer sheets on rayon from bamboo and on stretch or moisture-wicking knits; softener coats the fibers. Purple's care line for SoftStretch is machine wash cold.
• Keep two sets per bed and rotate them; each lasts longer.

Find us

Mattress Central, 3319 Glendale Blvd, Atwater Village, Los Angeles 90039, open daily 9 AM to 8 PM. Bring your mattress height and size, or browse bedding, protectors, pillows, king and California king mattresses online. Free delivery anywhere in the US. Around Los Angeles our own team sets it up and takes your old mattress away (California orders). Mattresses carry a 120-night comfort exchange; bedding does not, so measure first. Call (323) 522-3410 or read the FAQ.