The best fabric for a blanket is anti-pill polar fleece for most people - warm, cheap, machine washable and it needs no hemming because it does not fray. Brushed cotton wins if you want breathability, sherpa if you want weight. But before the fabric, sort out the size, because standard cloth is 150cm wide and every blanket wider than that needs two widths joined.
That single fact decides your metreage, your cost and how long the project takes. A lap throw and a single-bed blanket are an hour's work from one length of fleece. A double or king blanket is a different job with a seam down the middle. Get the size right first and the rest follows.
UK blanket and throw sizes
There is no British Standard for blanket sizes and every manufacturer differs, so these are the practical dimensions that fit UK beds and UK sofas. Finished sizes, before seam allowances.
| Blanket | Finished size (cm) | Wider than 150cm? | Notes |
|---|---|---|---|
| Pram / crib blanket | 75 x 100 | No | Two fit across one width of fabric |
| Baby blanket / cot top | 100 x 120 | No | The standard gift size |
| Toddler / cot bed | 110 x 140 | No | Fits a 70 x 140cm cot bed with overhang |
| Lap blanket | 120 x 150 | No | Wheelchair, armchair, car |
| Sofa throw (standard) | 130 x 170 | No | The most popular size to make |
| Large sofa throw | 150 x 200 | Just fits | Uses the full bolt width with no spare |
| Single bed, tucked | 180 x 230 | Yes | Needs a joined panel |
| Double bed | 230 x 250 | Yes | Two widths joined |
| King bed | 260 x 260 | Yes | Two widths joined, both trimmed |
| Super king | 280 x 280 | Yes | Two widths joined, with little to trim |
Note the pattern. Everything up to and including a large sofa throw comes out of a single length of 150cm cloth, because you turn the fabric sideways: the bolt width becomes the length of the blanket, and the length you buy becomes its width. Everything above that crosses the line.
The width problem
Most dressmaking and furnishing fabric in the UK comes off a 150cm bolt. Some quilting cotton is 110cm; some curtain and sheeting fabric is 220 or 280cm wide. Check the listing before you calculate anything, because a 110cm-wide fabric turns even a standard sofa throw into a joining job.
At 150cm, the arithmetic is straightforward:
- Blanket up to 150cm on its longest side that matters: buy one length. A 130 x 170cm throw needs 1.8m — the 150cm bolt width becomes the 130cm dimension after hemming, and your 1.8m becomes the 170cm length.
- Blanket wider than 150cm: buy two lengths and join them. A 230 x 250cm double needs 2 x 2.4m, seamed along the long edges, giving about 294cm of width before you trim back to 250cm.
- The trim is not waste you can avoid. The selvedges must come off — they are woven tighter than the body of the cloth and will pucker the seam and pull the blanket out of square after washing.
Joining two widths invisibly
The mistake is putting the seam down the middle. Two full widths joined centrally give you a ridge running straight up the sleeper's spine, which you feel. Do it the way curtain makers do (the same maths is in how much fabric for curtains):
- Cut both selvedges off both lengths — 1 to 1.5cm each side.
- Use one full width as the centre panel. Cut the second width in half lengthways.
- Join a half-width to each side of the centre panel, so the two seams sit roughly a third of the way in from each edge and the blanket is symmetrical.
- Press the seams open flat on a woven fabric. On fleece, press them to one side with a cool iron and a pressing cloth, or leave them and topstitch 5mm either side to keep them lying flat.
- Match any pattern or nap direction across the join before you pin. On brushed cotton and sherpa, a reversed nap shows as a colour change in daylight.
The three-panel rule. For any blanket wider than 150cm, plan for three panels — one full width in the centre, two half widths at the sides — not two. It uses the same metreage, hides the seams where nobody lies, and it is the reason a homemade double blanket either looks professional or looks homemade.
Fabric options compared
Fleece (polar and anti-pill)
The default, and the right default. Warm for its weight, machine washable at 30°C, available in every colour, and it does not fray — you can genuinely leave the edges raw. At £2 to £5 a metre it is the cheapest warm blanket you can make. Anti-pill is worth the small premium on anything washed weekly; the mechanism is explained in polar fleece vs anti-pill fleece. Its weakness is breathability: fleece is polyester and it traps moisture as well as heat, so hot sleepers dislike it.
Brushed cotton
Cotton woven and then napped on one or both faces, so it feels soft and warm but still breathes. Warmer than plain cotton, cooler than fleece, and the best choice for anyone who overheats or for a blanket that will be used year-round. It frays, so it must be hemmed, and it shrinks — pre-wash before cutting or your carefully measured throw comes out 5cm short (how to wash fabric properly covers temperatures). Typically £2 to £6 a metre.
Brushed cotton vs flannel
These are largely the same thing and the words are used interchangeably in UK shops. Strictly, flannel is the traditional term for a soft napped fabric, originally wool; brushed cotton is the modern cotton version, and "cotton flannel" and "flannelette" describe the same napped cotton cloth. If a listing offers you both, look at the GSM and the fibre content rather than the name. Double-brushed (napped both sides) is warmer and softer than single-brushed. More on the cloth itself in what is brushed cotton.
Sherpa and teddy fleece
Curly, bulky, one-sided pile at 320 to 450gsm. Beautiful as a backing, poor as a whole blanket — two layers of sherpa is unwieldy and sheds badly when cut. Use it on one face with fleece or brushed cotton on the other; the fur and sherpa fleece range is the place to start. Expect £5 to £9 a metre, so it roughly doubles the cost of a project.
Wool and wool blends
The traditional answer, and still the warmest per gram. Wool breathes, regulates temperature and lasts decades. It is also the most expensive option, usually needs a hand or wool-cycle wash, and can irritate sensitive skin — bind the edges with satin or cotton binding rather than leaving wool against a neck. A wool-blend blanket is an heirloom project rather than a Saturday one. See the wool fabrics for weights and blends.
Quilted cotton with wadding
Two layers of quilting cotton with wadding between, quilted through. The most work by a long way and the most rewarding: fully washable, breathable, and you can control the warmth precisely by choosing the wadding loft. Budget for the middle layer as well as the two outer ones — see the quilt wadding range and our wadding, interfacing and stuffing guide for loft and fibre choices.
Metreage and cost by size and fabric
All from 150cm-wide fabric, including 4cm total for hems and a 3% margin for squaring up. Prices are worked examples at indicative rates — check the current listing and rerun the sum. For everything else you might make, see how much fabric you need.
| Blanket | Single layer | At £1/m | At £3/m | Two-layer (no-sew or lined) | Two-layer at £3/m |
|---|---|---|---|---|---|
| Pram, 75 x 100cm | 0.8m | £0.80 | £2.40 | 1.6m | £4.80 |
| Baby, 100 x 120cm | 1.0m | £1.00 | £3.00 | 2.0m | £6.00 |
| Toddler, 110 x 140cm | 1.2m | £1.20 | £3.60 | 2.4m | £7.20 |
| Lap, 120 x 150cm | 1.3m | £1.30 | £3.90 | 2.6m | £7.80 |
| Sofa throw, 130 x 170cm | 1.8m | £1.80 | £5.40 | 3.6m | £10.80 |
| Large throw, 150 x 200cm | 2.1m | £2.10 | £6.30 | 4.2m | £12.60 |
| Single, 180 x 230cm | 2 x 1.9m = 3.8m | £3.80 | £11.40 | 7.6m | £22.80 |
| Double, 230 x 250cm | 2 x 2.4m = 4.8m | £4.80 | £14.40 | 9.6m | £28.80 |
| King, 260 x 260cm | 2 x 2.7m = 5.4m | £5.40 | £16.20 | 10.8m | £32.40 |
| Super king, 280 x 280cm | 2 x 2.9m = 5.8m | £5.80 | £17.40 | 11.6m | £34.80 |
Look at the jump between a large throw and a single bed blanket: 2.1m to 3.8m, because you crossed the 150cm line and now buy two lengths to make one panel. If your blanket is close to that boundary, shrinking it by 10cm can halve the fabric bill.
Three ways to make it
1. No-sew fleece — one hour, scissors only
Two layers of fleece, wrong sides together, edges matched. Cut a 10cm square out of each corner through both layers. Cut a fringe all round: strips 2.5cm wide and 10cm deep, through both layers at once. Knot each matching pair in a double knot. A lap blanket takes about an hour and costs £7.80 in fleece at £3 a metre. Cut the fringe at least 8cm deep — shorter fringes untie themselves in the wash.
2. Single-layer hemmed — 45 minutes, one seam type
The most efficient blanket there is. Square up the fabric, then either turn a double 1cm hem all round on a woven fabric and straight stitch, or on fleece turn a single 1cm hem and zigzag. Mitre the corners by folding the point in at 45° before turning the sides. On fleece you can skip hemming altogether and finish the edges with a wavy rotary blade or pinking shears. A 130 x 170cm throw in £3 fleece costs £5.40, a fraction of the price of a shop-bought throw.
3. Two-layer with wadding — an afternoon, and the warmest
Top fabric, wadding, backing fabric. Layer them, smooth out from the centre, and pin or spray-baste generously (how to use wadding the right way walks through basting). Quilt through all three layers — straight lines 15 to 20cm apart is plenty, and diagonal lines forgive wobbles better than a grid does. Then either bind the edges with 5cm double-fold binding, or use the "birthing" method: sew all three layers right sides together with a 20cm gap, turn it through, close the gap and topstitch. Budget the wadding at roughly the same metreage as one face.
Use a walking foot for anything over a metre. Thick layers feed unevenly — the bottom one travels faster than the top — and over two metres of blanket that becomes a rippled seam and a twisted edge. A walking foot fixes it outright. Failing that, pin every 10cm, lengthen your stitch to 3.5mm and support the weight of the blanket on a chair rather than letting it hang.
Baby blankets
For a baby blanket the sewing is the easy part. Cotton, brushed cotton, cotton muslin and bamboo are the fabrics parents most often ask for, because they breathe: air and moisture move through them, and they do not hold heat the way polyester fleece does. Cellular cotton blankets — the ones with the open holed weave — are made that way for the same reason. Keep the construction simple, use a single layer or a light two-layer with no wadding, and avoid ribbons, buttons, appliqué, pompoms and anything else that can come loose. Wash the finished blanket before it is used, in non-biological detergent and no fabric softener.
What to buy
For a first blanket, buy 1.8m of 270gsm anti-pill fleece and make a hemmed sofa throw. It costs a few pounds, it takes an evening, it does not fray, and it will tell you whether you want to spend an afternoon on a quilted one. If you already know you want breathability, buy 1.8m of brushed cotton instead, wash it before you cut it, and hem it double. For other cold-weather projects, see autumn fabrics UK. Either way, work out the finished size first and check the bolt width on the listing — that is the number that decides everything else.
Frequently asked questions
What is the best fabric for a blanket?
Anti-pill polar fleece, for most people. It is warm for its weight, it does not fray so it needs no hemming, it costs a few pounds a metre and it survives a weekly wash. Brushed cotton is the better choice if you want a blanket that breathes, and sherpa or a wool blend if you want weight and a more expensive look.
How much fabric do I need for a throw?
A standard UK sofa throw is around 130 x 170cm. From 150cm-wide fabric that is a single 1.8m length, with the width of the bolt becoming the length of the throw — no joining seam needed. At an indicative £3 a metre that is £5.40 of fabric, and a hemmed throw takes about an hour to make.
What size is a single blanket?
A single bed blanket is usually 180 x 230cm if you want it to tuck in, or around 150 x 200cm as a top blanket that sits on the duvet. The 150cm figure matters because standard fabric is 150cm wide, so a 150cm-wide blanket comes from one length of cloth and anything wider needs two widths joined.
Can you make a blanket without sewing?
Yes. The no-sew fleece blanket uses two layers of fleece, wrong sides together, with 10cm squares cut from each corner and a 2.5cm-wide, 10cm-deep fringe cut all round through both layers. Knot each matching pair of strips. Fleece does not fray, so the raw edges are permanent, and it takes about an hour with scissors alone.
