The Four Decisions Behind Every Shirt Fabric

Fabric selection feels overwhelming because it is usually presented as an endless catalogue of names: poplin, oxford, jersey, pique, twill, flannel, chambray. In reality every one of those names is just a shorthand for four underlying decisions. Once you can see the four, the catalogue stops being intimidating.

A “180 GSM combed cotton single jersey” is not jargon; it is those four decisions stated in order. Weight (180 GSM), finish (combed), fibre (cotton), structure (single jersey). Once you can read a spec like that, you can write one, and once you can write one, no supplier can hide behind vagueness.

Knit or Woven: The First Fork in the Road

This single decision determines what kind of shirt you are making, and it is not reversible. Everything else follows from it.

Knits: loops, and therefore stretch

Knitted fabric is made from a single yarn looped through itself, like a hand-knitted jumper at microscopic scale. Because the loops can pull open, knits stretch and recover. They are soft, comfortable, forgiving of body movement, and they drape close to the body.

Used for: t-shirts, polos, henleys, long-sleeve tees, base layers, most casual shirts. If it pulls over your head without buttons, it is almost certainly a knit.

Wovens: threads crossing at right angles, and therefore structure

Woven fabric is made from two sets of yarns crossing perpendicular to each other on a loom. There are no loops to open, so woven fabric has essentially no stretch (unless elastane is added). It holds a crisp shape, presses sharply, and drapes with structure rather than clinging.

Used for: dress shirts, flannels, overshirts, denim shirts, camp collars. If it has a button placket down the front and holds a collar shape, it is woven.

GSM: The Single Most Useful Number

GSM means grams per square metre. It is the weight of the fabric, and because fabric is bought by weight, GSM acts as close to a direct multiplier on your fabric cost. It is also the number customers feel first, before they have consciously registered anything else about your product.

The chart to bookmark

Heavier is not automatically better

This is worth saying clearly, because the streetwear market has convinced a lot of founders otherwise. A 260 GSM tee is a genuine statement piece and it feels expensive. It is also hot, slow to dry, and a bad seller in Dubai, Miami or Karachi, where a 160 GSM tee sells year-round.

Choose the weight your market will actually wear. Weight is a tool, not a virtue. Read our wider fabric guide for the full breakdown.

Fibre: What the Shirt Is Actually Made Of

Fibre determines how the shirt feels, how long it lasts, how it washes, and what it costs. Here is the honest comparison.

Blends are engineering, not compromise

New founders often assume “100% cotton” is automatically the premium choice. Frequently it is not. A 60/40 cotton-poly work shirt survives industrial laundering that would destroy pure cotton. A tri-blend tee (cotton, polyester, viscose) is softer and drapes better than any of the three alone. A 95/5 cotton-elastane shirt keeps its fitted shape all day.

Choose the blend that solves your garment's actual problem, not the one that reads best on a hang tag.

The cotton grades that matter

• Carded cotton. The basic grade. Shorter fibres, slightly coarser, cheapest.
• Combed cotton. Short fibres combed out, leaving longer ones. Noticeably smoother and stronger. This is what you want for a quality tee, and it is a small price step.
• Ring-spun. Yarn spun by twisting and thinning the strands, producing a softer, finer yarn. Combed ring-spun is the sweet spot for premium tees.
• Mercerised. Treated with caustic soda for a subtle lustre and better dye uptake. Common on quality polos.

The Right Fabric for Each Shirt Type

T-shirts

Specify: single jersey, 180–200 GSM, 100% combed ring-spun cotton. That is the reliable, sells-everywhere default.

For streetwear: go to 220–260 GSM heavy jersey, and consider a garment wash for a lived-in hand feel. This is the weight that makes a boxy oversized tee hang correctly rather than flapping.

For hot climates: stay at 140–170 GSM, or use a cotton-poly blend that dries faster. See our t-shirt manufacturing page.

Polo shirts

Specify: pique knit, 200–260 GSM, combed cotton or a cotton-poly blend. Pique's textured honeycomb structure is what gives a polo its body and stops the collar collapsing.

For corporate and uniform use: a 60/40 poly-cotton pique resists wrinkling through a long day and survives frequent washing. For retail polos, stay cotton-rich for feel.

Dress shirts

Specify: woven poplin, 110–150 GSM, 100% cotton or cotton with a small elastane percentage for comfort.

Alternatives: oxford weave (heavier, more textured, more casual), twill (softer, drapes better, resists wrinkles), chambray (lightweight, denim-look, casual).

Flannel and overshirts

Specify: brushed cotton twill, 170–220 GSM for a flannel shirt, 240–320 GSM for an overshirt or shacket. The brushing is what creates the soft, fuzzy hand; ask for double-brushed if you want it noticeably softer.

Performance and gym shirts

Specify: polyester or poly-elastane, 140–180 GSM, with a moisture-wicking finish. Do not use viscose here: it holds moisture rather than moving it, and it weakens when wet.

Finish: The Step Most Brands Forget

Finish is what happens to the fabric after it is made, and it is where a good shirt becomes a great one. It is also the part of the specification most first-time founders leave blank, which means the factory decides for them.

Real 2026 rates. Add them to your specification in the cost calculator.

How Fabric Choice Changes Your Cost

Fabric is 45 to 60 percent of a knit garment's cost. That single fact means fabric selection is not just an aesthetic decision, it is your primary cost lever, and the one place where a small change moves the price meaningfully in either direction.

The two multipliers

Fabric cost is driven by two things multiplied together: how much cloth the garment consumes (which GSM determines), and what that cloth costs per kilogram (which fibre determines).

Move a t-shirt from 180 GSM to 240 GSM and you are buying roughly a third more cloth. Move it from standard cotton to GOTS organic and the cloth itself costs about a third more. Do both, and you have not made a small adjustment; you have materially repriced your product.

Where to spend, and where not to

If your budget is tight, here is the honest priority order:

1. Combed ring-spun cotton over carded. Small cost, immediately noticeable. Do this first.
2. The right GSM for your market. Not the heaviest, the right one. A 200 GSM tee that sells beats a 260 GSM tee that sits.
3. An enzyme wash. Under a dollar, and it transforms the hand feel of a mid-weight tee.
4. Organic certification. Last, and only if your customers genuinely buy on it, because it costs a great deal and feels identical.

Six Fabric Mistakes That Cost Brands Money

1. Choosing from a screen

The single most common and most expensive fabric mistake. A 180 GSM jersey and a 240 GSM jersey are indistinguishable in a photograph and completely different products in the hand. Order swatch cards. Always.

2. Not stating GSM at all

“Premium cotton” is not a specification, it is an adjective. If your quote does not state a GSM, you have not specified a fabric, and any two suppliers quoting on it are quoting on different products. This is exactly how brands end up comparing prices that were never comparable.

3. Assuming heavier means better

A 260 GSM tee is a genuine statement piece. It is also hot, slow to dry, and a poor seller in warm markets. Choose the weight your customers will actually wear, not the weight that sounds most impressive.

4. Skipping the wash test

Wash the pre-production sample exactly as your care label instructs, then measure it again. If it moved, the fabric needs more treatment. This ten-minute step prevents the most common fabric disaster there is: a garment that arrives beautiful and shrinks a full size on the customer's first wash.

5. Not recording the mill and article number

If your spec file says “190 GSM cotton jersey” but not which mill and which article, your reorder will be approximately similar rather than identical. Customers notice. Insist the mill name and article number are archived with your patterns.

6. Ignoring the climate you sell into

This is the one nobody warns you about. A 450 GSM hoodie and a 260 GSM tee are excellent products in Chicago and terrible ones in Dubai, where the same brand should be running 140 to 180 GSM cotton and breathable blends year-round. Specify for the market, not for the trend. Our locations page covers what each market actually orders.

How to Actually Choose, in Practice

Here is the sequence that works, and it takes about a week.

Step 1: Buy the shirt you wish you were selling

Find the closest thing on the market to what you want to make and buy it. Wear it. Wash it. This physical object tells you more than any fabric catalogue, and a factory can reverse-engineer it.

Step 2: Ask for its likely spec

Send it to your manufacturer and ask: what is this, approximately? A competent factory will tell you it is roughly a 190 GSM combed ring-spun single jersey with an enzyme wash. Now you have a starting point rather than a blank page.

Step 3: Order swatch cards, and touch them

Have your factory send labelled swatches with GSM, blend and finish marked on each. Lay them out. Handle them. The decision that takes two weeks of internal debate on a screen takes about thirty seconds with the fabrics in your hand.

Step 4: Sample in your two best candidates

If you genuinely cannot choose between two fabrics, sample the shirt in both. It costs one extra sample fee, which is credited against your bulk order anyway, and it removes all guesswork permanently.

Step 5: Wash-test before bulk

Wash the sample exactly as your care label will instruct. Measure it before and after. If it moved, the fabric needs more treatment. This single step prevents the most common and most expensive fabric disaster there is.

Step 6: Record the mill and article number

Once you approve a fabric, insist the mill name and article number go into your spec file. That is what makes your reorder identical rather than approximately similar, and it is the difference between a brand and a series of one-off products.

Frequently Asked Questions