What Is 40s Cotton? 21s–40s Yarn Count for T-Shirts

What Is 40s Cotton? 21s–40s Yarn Count for T-Shirt Fabric

40s cotton refers to cotton yarn with an English Cotton Count of Ne 40. In this system, a higher number means a finer yarn. A single Ne 40 yarn may also be written as 40/1 or “40 singles.”

It does not mean the fabric contains 40% cotton. It also does not specify the fabric weight or guarantee a particular level of quality.

In cotton single jersey T-shirts, 40s yarn can help create a smooth surface and a refined handfeel. However, opacity, durability and overall quality still depend on cotton quality, spinning method, knit construction, GSM and finishing.

So, is 40s cotton better than 21s or 32s cotton? That depends on the T-shirt you want to make.

This guide explains how 21s, 24s, 30s, 32s and 40s cotton yarn counts affect T-shirt fabric—and what buyers should confirm before approving an OEM bulk order.

Quick Answer: Which Cotton Yarn Count Should Buyers Choose?

For T-shirt development, these are useful starting directions:

• 21s–24s: coarser yarns to consider for substantial, structured everyday tees.
• 30s–32s: a practical starting range for core T-shirts that need a balance of handfeel, structure and cost.
• 40s: finer yarn to consider for a smoother, more refined fabric surface.

These are sampling directions, not fixed performance grades. A uniform tee, an everyday retail basic and a soft premium fashion T-shirt have different jobs. Compare finished samples that match your intended weight, colors and use.

Do Not Confuse 40s Cotton, 40% Cotton, and 40×40 Cotton Fabric

These expressions look similar in a search result or supplier message, but they describe different specifications.

For this article, the focus is 40s cotton yarn used in knitted T-shirt fabric. For help reading percentages on a fabric card or label, see our guide to fabric composition.

What Is 40s Cotton?

40s cotton means cotton yarn with a nominal count of Ne 40. It is finer than Ne 32, Ne 30, Ne 24 or Ne 21 yarn under the same numbering system.

On a supplier’s fabric card, “40s cotton fabric” usually describes fabric made with that yarn count. The card should also identify the fiber composition, ply, knit structure and finished weight. If the description says only “cotton 40,” ask whether the supplier means Ne 40 and whether it is a single or plied yarn.

40s cotton single jersey is often considered for elevated T-shirts, soft casual tops and lightweight retail programs. It can support a clean surface and a refined drape, but the finished sample still needs to meet the product brief.

A poorly controlled 40s fabric can pill, twist or lose its shape after washing. A well-made 30s or 32s fabric may perform better. For OEM buyers, the useful question is how the yarn, knitting and finishing work together—and whether the approved result can be repeated in bulk.

What Is Cotton Yarn Count?

Yarn count describes yarn fineness or linear density. For cotton and other short-staple spun yarns, buyers often see the English Cotton Count written as Ne, Ncc or with an “s” after the number.

In expressions such as 21s cotton, 30s cotton and 40s cotton, the “s” is commonly used to indicate the cotton-count notation. It does not represent a fiber percentage. Confirm the numbering system when comparing supplier quotations.

The English Cotton Count is an indirect system: the higher the Ne number, the finer the yarn.

In practical terms:

• Ne 21 is coarser than Ne 30.
• Ne 30 is coarser than Ne 40.
• Ne 40 is finer than Ne 21.

The system is based on the number of 840-yard hanks in one pound of yarn. Therefore, a nominal Ne 40/1 yarn represents:

40 × 840 yards = 33,600 yards per pound.

CottonWorks explains the English Cotton Count as an indirect yarn-numbering system in which a higher number means a finer yarn.

This definition explains the number. It does not predict the finished T-shirt by itself. Knitting, dyeing, finishing and garment washing can all change the final handfeel and performance.

What Do 40/1, 40 Singles, and 40/2 Cotton Mean?

In these cotton-yarn specifications, the number before the slash identifies the component yarn count. The number after the slash identifies the number of single yarns in the construction.

40/1 cotton means one single Ne 40 yarn. Suppliers may also call it 40s singles or 40 singles cotton.

40/2 cotton means two Ne 40 single yarns are twisted together to create a two-ply yarn. Although each component is Ne 40, the combined yarn has greater linear density than one 40/1 single yarn. Plying can improve strength and evenness, but does not guarantee the performance of the finished fabric.

This distinction matters because a quotation that says only “40s cotton” may not tell you whether the yarn is single or plied.

For many cotton single jersey T-shirts, 40/1 is the more relevant specification. Still, confirm the ply instead of assuming it. A 40/2 fabric is not a direct substitute for a 40/1 fabric.

Yarn Count vs GSM for Single Jersey T-Shirts

Yarn count and GSM are related, but they are not the same specification.

Yarn count tells you how fine the yarn is. GSM tells you how much the finished fabric weighs per square meter.

A 32s cotton single jersey at 160 GSM and a 32s single jersey at 220 GSM use the same nominal yarn count, but their weight and finished character differ.

The reverse is also true. Two single jersey fabrics can both weigh 160 GSM while using different yarn counts. Their opacity, drape and surface appearance may differ because of yarn quality, stitch length, knitting settings and finishing.

That is why buyers should not use a fixed chart that treats one yarn count as equal to one GSM. Compare actual samples, including white and light colors, rather than predicting coverage from yarn count alone.

For detailed weight planning, see our fabric weight guide.

Is a Higher Yarn Count Always Better?

No. Finer yarn can help create a refined surface, but the rest of the fabric specification must support that result.

Fiber quality sets the limit

Finer yarn requires suitable fiber quality and spinning control to maintain strength and evenness. If those are poorly controlled, yarn irregularity, hairiness or weakness can affect the knitted fabric.

That is why a good 40s cotton fabric can feel premium while another 40s sample feels uneven or unreliable.

What is 40s combed cotton?

40s combed cotton combines two specifications: “40s” identifies the yarn count, while “combed” describes the preparation of the cotton fibers before spinning.

Combing removes short fibers from the fiber mix. It does not change Ne 40 into a different yarn count, and a 40s specification alone does not confirm that the cotton is combed. A supplier may write “cotton combed 40s” on a fabric card; the two terms should still be read separately.

Spinning method is another part of the specification. “40s ring-spun cotton” identifies count and spinning method, but does not by itself confirm whether the cotton was combed. Ask the supplier to state preparation and spinning method separately.

The same distinction applies to 32s fabric. A 32s combed ring-spun cotton single jersey and a 32s carded open-end cotton single jersey can have different surface appearance and handfeel despite sharing the same count.

Approve the finished fabric, not just the number

With any of these yarn counts, buyers should check:

• Opacity in white and light colors.
• Surface evenness and handfeel.
• Pilling after the agreed test or wash routine.
• Shrinkage and side-seam twisting.
• Consistency between the approved sample and bulk fabric.

These are fabric approval checks, not defects that can be predicted from “40s” alone. If the sample fails, review its full construction and finishing before changing the yarn count.

21s vs 24s vs 30s vs 32s vs 40s Cotton

Each yarn count can support a useful T-shirt direction. The differences below are relative, not fixed promises. Cotton quality, ply, knit density, GSM and finishing can change the outcome.

21s cotton single jersey: substantial and practical

21s cotton single jersey is a useful direction when the buyer wants a substantial or rugged casual handfeel. It can work for uniform tees, workwear-inspired products, promotional programs and heavier basics when paired with a suitable weight and construction.

If you want that substance with a cleaner surface, specify cotton preparation and spinning method. “21s” alone does not tell the supplier how soft or smooth the finished tee should feel.

24s cotton: a middle option for casual basics

24s sits between coarser 21s yarn and finer 30s–32s yarn. It can support casual basics and merch tees where the brief calls for some structure without the coarsest yarn direction.

For bulk orders, check whether the sample handfeel remains acceptable after washing. Initial softness may partly reflect a finish that changes with laundering.

30s vs 40s cotton: balance or a finer yarn direction?

30s cotton is a practical starting point for core T-shirts. With appropriate yarn quality and finishing, it can balance softness, structure and cost.

The measurable difference between 30s and 40s cotton is yarn fineness: Ne 40 is finer than Ne 30. A 40s construction may support a more refined surface, but it is not automatically softer, lighter or more durable than every 30s fabric.

If a well-made 30s sample already meets your handfeel and appearance targets, moving to 40s may not add enough value to justify the change.

32s vs 40s cotton: compare the complete samples

32s cotton can work for everyday retail basics, club or team tees and private-label collections. For many core T-shirt programs, 30s–32s combed ring-spun cotton single jersey is a sensible place to begin sampling.

Compared with 32s, 40s uses finer yarn. To judge whether that difference benefits your range, compare samples in the intended colors and finished weight. Review surface appearance, drape, coverage and wash results together.

Choose the sample that meets the brief. Do not assume that 32s guarantees stability or that 40s guarantees a premium finish.

40s cotton: a refined surface with construction choices

40s yarn count is useful when the product brief calls for a smoother surface, softer touch or more refined drape. It can suit premium basics, minimalist fashion tees and lightweight-looking retail programs.

If a 40s cotton sample is too transparent, first review the GSM, knit density, color and finishing. Switching to 32s is one option, but it is not the only one. A revised 40s construction may deliver the coverage you need while keeping the intended handfeel.

How Should a Buyer Choose the Right Yarn Count?

Start with the job of the T-shirt. Define the intended silhouette, color range, retail price and finished handfeel before selecting fabric samples.

For a substantial basic, begin by comparing suitable 21s–24s constructions. For a versatile core tee, compare 30s–32s. When a refined surface is central to the brief, include a 40s option.

Then wash the samples under the agreed care conditions and review them again. Check whether the fabric still has the coverage, shape and surface appearance you approved initially.

The final decision should come from this comparison. A yarn-count label is useful for narrowing the options; the finished sample confirms the choice.

What To Specify in Your PO

Writing only “40s cotton” or “32s cotton” leaves too much room for interpretation.

For an OEM bulk order, confirm:

• Yarn count and numbering system, such as Ne 40.
• Ply, such as 40/1 singles.
• Cotton preparation, such as combed or carded.
• Spinning method.
• Fiber composition and knit structure.
• Target GSM and permitted tolerance.
• Agreed opacity, shrinkage, pilling, spirality and colorfastness requirements.
• Approved sample and bulk-fabric reference.

A clearer starting line could look like this:

100% cotton single jersey, Ne 40/1 combed ring-spun yarn, target GSM and tolerance as agreed; opacity, shrinkage, pilling, spirality and colorfastness requirements confirmed before bulk production.

For a core tee, a buyer might instead specify:

100% cotton single jersey, Ne 32/1 combed ring-spun yarn, 160 GSM ±5%; wash performance and approved PP sample requirements confirmed before bulk production.

These are specification examples, not universal acceptance standards. Set the actual weight, tolerance, test methods and pass criteria for your product. Use the approved PP sample and fabric reference to define the result the factory must repeat.

For the wider inspection process, use an apparel quality control checklist.

FAQ: 40s Cotton and T-Shirt Yarn Count

What is 40s cotton?

40s cotton refers to cotton yarn with a nominal English Cotton Count of Ne 40. A higher Ne number means finer yarn. The count does not specify fabric weight, ply, cotton preparation or overall quality.

Is 40s cotton the same as 40% cotton?

No. “40s” describes yarn count; “40% cotton” describes fiber composition. Confirm composition separately if you need a 100% cotton fabric or a specific blend.

What is 40s yarn?

40s yarn has a nominal English Cotton Count of Ne 40. A single yarn may be written as 40/1 or 40 singles. The count notation itself does not identify the fiber composition.

What does 40s two-ply cotton mean?

It usually means two Ne 40 single cotton yarns have been twisted together, commonly written as 40/2. The combined yarn has greater linear density than one 40/1 single yarn, so the two specifications are not interchangeable.

Is 40s cotton better than 32s cotton for T-shirts?

Not always. Ne 40 yarn is finer than Ne 32, but the better fabric depends on yarn quality, knitting, GSM, finishing and the product brief. Compare actual samples for handfeel, coverage and wash performance.

What is the best yarn count for cotton single jersey T-shirts?

There is no single best count. For core T-shirts, 30s–32s is a practical sampling range. Consider 21s–24s for a substantial direction and 40s for a more refined surface, then confirm the finished fabric against your requirements.

Does a higher yarn count pill less?

Not automatically. Pilling also depends on fiber properties, yarn hairiness, spinning, knit construction, finishing and wear. Use an agreed pilling test rather than treating yarn count as proof.

What does 40×40 cotton fabric mean?

In many woven-fabric specifications, 40×40 means 40-count yarn is used in both warp and weft. It does not state thread density and is different from 40s single jersey or 40% cotton.

Choosing a Fabric for Your T-Shirt Program

40s cotton identifies yarn fineness. A usable bulk specification also needs ply, preparation, spinning method, composition, construction, finished weight and agreed performance requirements.

If you are developing custom T-shirts, cotton jersey tops or private-label apparel, Qiandao can help compare 21s–40s yarn directions, prepare samples and confirm the fabric before bulk production. Once the fabric direction is selected, review how MOQ, sampling and bulk production lead time affect your development plan.

If you are planning cotton or cotton-rich styles for a golfwear collection, share your intended garment, target handfeel, colors and quantity through our custom golf apparel quote page. We can review the fabric direction before sampling.