A twin mattress is 38 inches wide and 75 long, and a twin XL is 38 by 80, by the Better Sleep Council's chart. The width is the same. The XL adds five inches of length, which turns a child's bed into one an adult can stretch out on.
At Merit Home Furniture on Vancouver Island, 25 of our 62 mattress listings come in twin XL or twin long and 31 come in twin. Where a maker prices the two sizes apart, the XL costs $50.00 to $300.00 more. The real catch is bedding, because a twin fitted sheet will not stretch over an XL.
How much bigger is a twin XL than a twin, and do they fit the same?
A twin XL is five inches longer than a twin and exactly as wide. In area that is 3,040 square inches against 2,850, a gain of 190 square inches, or about 6.7 percent. All of it lands at the foot, where a tall sleeper's feet end up.
The similarities between twin and twin XL stop at the width. Both are 38 inches across, both sleep one person, and both suit a narrow room. The differences are length, bedding and frames. A twin XL is as long as a queen or king, so its frame, fitted sheet and protector are all cut for 80 inches.
So no, they do not fit the same. A twin XL laid on a twin frame runs five inches past the end with nothing under it. On a slatted platform that overhang sags, and on a rail frame it hangs in the air. A twin on an XL frame leaves a five-inch gap where the slats show.
Twin and twin XL dimensions in inches, centimetres and feet
Makers print slightly different figures for the same size. The Better Sleep Council gives the round chart sizes that frames are built around. Sealy Canada lists finished mattresses up to an inch shorter, and says actual size may vary by half an inch to an inch.
| Twin | Twin XL | |
|---|---|---|
| Better Sleep Council chart | 38 x 75 in | 38 x 80 in |
| Sealy Canada finished size | 38 x 74 in | 38 x 79.5 in |
| Restonic's own chart | 38 or 39 x 75 in | 39 x 80 in |
| Chart size in centimetres | 97 x 191 cm | 97 x 203 cm |
| Length in feet | 6 ft 3 in | 6 ft 8 in |
| Sleeping area | 2,850 sq in | 3,040 sq in |
| Two side by side | 76 x 75 in, not a standard size | 76 x 80 in, a king |
The same chart settles the twin XL vs double question. The Better Sleep Council lists a double at 53 by 75, which makes it 15 inches wider than a twin XL and five inches shorter. Every other size sits on our full chart.
Is a single bed the same size as a twin?
A single and a twin are the same mattress under two names. The Better Sleep Council's chart heads the size "twin (or single)". A single XL is likewise a twin XL, and the same chart also calls it twin extra-long. When a used bed or a hand-me-down frame is sold as a single, expect 38 by 75 unless the label says XL.
Twin or twin XL: which is better for the person sleeping on it?
Which is better depends on the sleeper's height and how many years the bed has to last. A twin is 6 feet 3 inches long. The Better Sleep Council says a twin "may be too short for some adults" and calls the XL "a good option for taller children" in the same breath.
My floor rule is shorter than any chart: a single sleeper over about five foot ten gets the XL. A teenager still growing gets it too, since a mattress outlasts a growth spurt.
Where a twin earns its place
Twin mattress pros: it is the cheaper size, and it fits bunk beds, captain's beds and trundles. It suits a young child or a small guest room. Sheets in twin are the easier size to find.
Where a twin XL earns its place
The XL suits a teenager, a single adult and anyone setting up a bed for years. The Better Sleep Council notes it is "a common size in college dormitories" as well. Two of them also make a split king.
Three buying considerations settle how to choose: the sleeper's height now and in five years, the length of the room, and the frame. The frame comes first. A bunk or captain's bed takes one size only.
What a twin XL costs over a twin at Merit
These are the mattresses on our pages that price the twin and twin XL differently. Prices were read on October 16, 2026, and are before applicable taxes.
| Mattress | Twin to twin XL |
|---|---|
| Restonic Prestige | $949.00 to $999.00, a step of $50.00 |
| Restonic Minto | $999.00 to $1,099.00, a step of $100.00 |
| Restonic Mondena | $1,388.00 to $1,488.00, a step of $100.00 |
| Restonic Notte | $1,388.00 to $1,488.00, a step of $100.00 |
| Restonic Treviso | $2,249.00 to $2,449.00, a step of $200.00 |
| Restonic Vernazza | $2,249.00 to $2,449.00, a step of $200.00 |
| Restwell Copper Hybrid (twin long) | $1,999.00 to $2,299.00, a step of $300.00 |
On those seven the XL runs 5.3 to 15.0 percent over the twin. On four of the six Restonics the twin XL is priced the same as a full, so the extra length costs what the extra width does. Bedding steps are smaller: Health Guard's microfiber sheets cost the same in both sizes, and its terry protector adds $10.00.
Twin XL sheets, protectors and comforters
Twin XL bedding is the one real hassle with the longer size. Fitted sheets and protectors are cut to the mattress, and a twin set stops five inches short of an XL's corners.
Can I use twin bedding on a twin XL?
The flat sheet, duvet and blanket mostly carry over, with less to tuck in at the foot. The fitted sheet and the mattress protector do not. Health Guard's Luxury Microfiber sheet set is $49.00 in twin and the same in twin XL. It fits mattresses up to 14 inches deep.
Where can I find twin XL sheets? Merit lists that set, and not every line offers the size: Health Guard's Bamboo Cotton set comes in twin, full, queen and king only. The twin XL Health Guard terry protector is $59.00, against $49.00 for the twin. Our page on what a protector does for the warranty explains why it matters.
Will a full-size comforter work on a twin XL?
A full-size comforter covers a twin XL with plenty to spare at the sides. It is made for a mattress about 53 inches wide, 15 more than the XL, so it drapes low. Whether it reaches the foot depends on the comforter, and measuring its length against 80 inches plus the mattress depth settles it.
Twin XL frames, bunk beds and split kings
Can a twin XL mattress go on a twin frame?
A twin frame stops at about 75 inches inside, so an XL hangs five inches past it. Youth beds on Merit's pages are where this bites. The Mako Youth Slide Bed with Trundle ($1,249.00) measures 43 by 80 inches outside. The Robbinsdale bunk bed ($949.00) is 79 inches long outside. Neither leaves room for an 80-inch mattress.
Health Canada's bunk bed page says to check "the bed's label for the suggested mattress size and thickness" first. It wants the mattress snug on all four sides, and guardrails at least 12.7 centimetres (5 inches) above the mattress top. A thick mattress eats into that rail height. Health Canada also says no child under 6 belongs on the top bunk.
Two twin XLs make a king. The Better Sleep Council says two twin extra-long beds pushed together are "about the same size as a king" at 76 by 80. That pair is the building block of a split king, and it is how a couple runs two of them side by side on an adjustable base.
Base widths differ by maker, and a base can run wider than the 38-inch mattress. Tempur-Pedic lists its Reflexion Boost at 39 by 80 in twin XL. That base is carried at our Campbell River store, so a call there gets our best price. Two bases from the same line keep the heights matched.
When a twin XL is the wrong buy
- A bunk, loft or trundle built for a twin. The XL will not go in, whatever it costs.
- Two regular twins bought to make a king. They come to 76 by 75, five inches short, and no king sheet fits snugly.
- An old frame sold as a single. The inside length decides it, not the tag.
- A room where every inch counts. The XL takes five more inches at the foot, plus whatever the frame adds.
At Merit the reverse warning matters just as much: the twin is the wrong buy for anyone near six feet. They get three inches of spare length at best, before the pillow takes its share.
Where the sizes and prices come from
- Better Sleep Council size chart, twin through California king, checked October 3, 2026.
- Sealy Canada FAQs, standard finished product dimensions, checked October 3, 2026.
- Health Canada advice on bunk bed mattresses and guardrails, checked October 3, 2026.
- Merit Home Furniture product listings, prices and maker dimensions as listed on October 3, 2026. Centimetres and areas are our own arithmetic, at 2.54 cm to the inch.
Buying a twin or twin XL from Merit in Duncan
Our Duncan store is at 107 Ingram St, open Monday to Saturday, 9 to 5. Call to ask which twin and twin XL mattresses are set up to lie on, and bring the sleeper's height. Mattress orders take 2 to 3 weeks to be ready for pickup or delivery.
From Duncan, a bed or mattress goes out for $150 across the Island with assembly; a Gulf Islands address is checked by phone, as we serve some islands. A mattress going a long way may need a different shipping method. Sheets and protectors can be added to that delivery, and pickup in Duncan is free. Our other stores set their own delivery terms, so ask them directly.
My final thoughts are short: match the mattress to the frame first, then to the sleeper. Our twin and twin XL mattresses, the youth and bunk beds and the sheets and protectors are all listed online. Other mattress guides cover the bigger sizes.