How Are T-Shirts Manufactured? T-Shirt Manufacturing Process

How Are T-Shirts Manufactured? T-Shirt Manufacturing Process for Running Apparel Buyers

T-shirts are manufactured through two connected stages: textile production and garment production.

Fibers are spun into yarn, and the yarn is knitted into fabric. The fabric is then dyed, finished, inspected, relaxed, spread, and cut into garment panels. Those panels are sewn together, printed or decorated, finished, checked, packed, and prepared for shipment.

That is the short answer to how T-shirts are manufactured.

For custom running T-shirts, however, the process needs more control than it does for a basic promotional tee. The manufacturer must also consider moisture behavior, stretch recovery, seam comfort, fit during movement, logo compatibility, wet appearance, and consistency across bulk fabric lots.

A T-shirt may look simple, but it is the result of many linked decisions. A weak fabric finish can affect shrinkage. A poor pattern can make a good fabric uncomfortable. Cutting errors can create twisting. The wrong print method can make a lightweight running shirt feel stiff and less breathable.

For B2B buyers, understanding the T-shirt manufacturing process is not about learning how to operate factory machines. It is about knowing what should be approved, where production risk enters the order, and which problems should be caught before bulk manufacturing begins.

T-Shirt Manufacturing Process Flow: 10 Steps

A typical T-shirt production process follows this sequence:

Product brief and tech pack → fiber, yarn, and fabric selection → fabric knitting → dyeing and finishing → pattern making and sampling → fabric spreading and cutting → sewing and assembly → printing and logo application → garment finishing and quality control → packing and shipment

This flow looks orderly on paper. In real production, several stages may overlap. Pattern development can begin while the factory is confirming fabric. Print tests may take place before the final sample. Packaging materials may be prepared while bulk sewing is still underway.

What matters is that the factory does not release the order into bulk production before the critical materials, fit, construction, and artwork are approved.

How Are Custom T-Shirts Made?

Custom T-shirts can be made through two different production routes.

The first route starts with existing blank T-shirts. A supplier purchases or stocks finished blanks, then adds a logo, graphic, neck label, or packaging. This can work for simple events, promotional orders, or programs where the buyer does not need full control over fabric, pattern, fit, or construction.

The second route is full cut-and-sew manufacturing. The T-shirt is developed from the fabric stage using a custom pattern, size chart, color, construction, logo method, labels, and packing requirements. This route gives the buyer more control, but it also requires clearer specifications and more approval stages.

This article mainly explains the full cut-and-sew T-shirt manufacturing process used for custom running and performance apparel.

Buyers who are unsure which route fits their program should first compare cut-and-sew T-shirts with private label or decorated blank T-shirts. That decision affects development work, product control, reorder consistency, and the type of manufacturer the brand needs.

Does One T-Shirt Factory Complete Every Production Step?

Not always.

One of the most common misunderstandings is that a T-shirt factory automatically spins yarn, knits fabric, dyes the material, prints the logo, sews the garment, and packs the order under one roof.

Some vertically integrated manufacturers control several of these operations. Many garment factories, however, coordinate with approved textile mills, dye houses, printing suppliers, trim suppliers, and testing laboratories.

For the buyer, the important question is not whether every machine is located in one building. The more useful question is whether the manufacturer can control the approved specifications, coordinate the suppliers, trace material lots, and keep the final garment consistent.

Step 1: Product Brief, Tech Pack, and BOM

Every T-shirt starts before any fabric is cut.

The first step is defining what the shirt is supposed to do. A race-day running tee, a general training shirt, a run-club top, and a low-cost event T-shirt may all look similar in a sketch, but they require different decisions.

A useful product brief should explain:

• Intended use and target customer
• Men’s, women’s, or unisex fit
• Athletic, standard, relaxed, or oversized silhouette
• Short sleeve, long sleeve, raglan, or set-in sleeve construction
• Fabric composition, approximate GSM, handfeel, and performance target
• Size range and garment measurements
• Logo artwork, placement, dimensions, and color
• Labels, hangtags, folding, and packing requirements
• Expected order quantity and target delivery window

The factory then translates this information into working production documents.

A tech pack normally records the garment design, measurements, construction, stitching, artwork, labels, and packing instructions. The bill of materials, or BOM, lists the fabrics, mesh panels, sewing thread, labels, transfers, reflective details, and packaging materials used in the style.

These documents do not need to be complicated for every project. They do need to be clear enough that the sample room, material suppliers, cutting department, sewing line, print supplier, and QC team are all working toward the same product.

A vague brief forces the factory to make assumptions. Those assumptions may appear acceptable in one sample but create pricing differences, repeated revisions, or inconsistent bulk production later.

Step 2: Fiber, Yarn, and Fabric Selection

When people ask how T-shirts are made, they often picture fabric being cut and sewn. The product actually starts much earlier.

Cotton T-shirts begin with cotton fiber, which is cleaned, spun into yarn, and knitted into fabric. Performance running T-shirts more commonly use polyester, nylon-spandex, mesh, or other performance materials, depending on the required handfeel, airflow, stretch, and dry time.

In many OEM projects, the garment manufacturer does not spin the yarn directly. Instead, the factory sources or develops fabric through a textile mill based on an approved performance target.

At this stage, composition alone is not enough.

Two fabrics labeled “100% polyester” can have very different:

• Surface smoothness
• Dry time
• Air permeability
• Stretch and recovery
• Pilling resistance
• Drape
• Handfeel
• Print performance
• Wet appearance

Yarn size, filament structure, knit density, fabric weight, and finishing all influence the final result.

For running T-shirts, buyers should begin with the use case. A lightweight race tee may prioritize airflow and fast drying. A run-club shirt may need a softer handfeel and a surface that accepts multiple sponsor logos. A training top may need better recovery and abrasion resistance.

Before moving forward, the buyer should approve a fabric swatch or sample garment rather than relying only on a composition description. The approval should record the fabric code, composition, GSM, color, usable width, stretch direction, handfeel, and required performance checks.

Step 3: Knitting the T-Shirt Fabric

Most T-shirts are made from knitted fabric rather than woven fabric.

Knitting forms connected loops of yarn. That looped structure gives T-shirt fabric its natural flexibility, drape, and comfort. Woven fabric is made by crossing yarns at right angles and normally has less natural stretch unless elastane or a mechanical stretch construction is added.

Many running shirts use single jersey, lightweight interlock, mesh, or other performance knit structures. However, a fabric name such as “polyester jersey” still does not fully define the product.

The final behavior also depends on:

• Yarn and filament type
• Machine gauge
• Knit density
• Fabric weight
• Hole size in mesh structures
• Elastane content
• Surface finishing

A smooth, tightly controlled face may work better for detailed logos. A more open structure may improve airflow but create greater opacity or snagging risk. A soft fabric may feel more comfortable in hand but still need enough stability to avoid stretching during cutting and sewing.

Some basic T-shirts are manufactured with a tubular knitted body and no side seams. Custom running T-shirts are more often cut from open-width fabric because side panels, shaped hems, athletic patterns, mesh zones, and custom grading require separate garment panels.

The buyer does not need to specify every knitting-machine setting. The buyer does need to approve how the finished fabric feels, stretches, recovers, prints, and behaves during use.

Step 4: Dyeing, Finishing, and Bulk Fabric Inspection

After knitting, the fabric moves into dyeing and finishing.

Dyeing creates the required color. Finishing helps control the fabric’s handfeel, surface appearance, dimensional stability, moisture behavior, and suitability for later garment production.

For a custom color, the dye house may first prepare a lab dip. This is a small color sample used for approval before the mill proceeds with bulk dyeing. Approval should consider the color under the agreed light source, because the same shade can appear different under daylight, retail lighting, or factory lighting.

Once bulk fabric arrives, it should not automatically move straight to cutting.

The factory should confirm relevant points such as:

• Fabric composition and GSM
• Usable width
• Color and dye-lot consistency
• Surface defects
• Shrinkage
• Spirality or skew
• Stretch and recovery
• Pilling or abrasion performance when required
• Moisture behavior and dry time
• Print and heat-transfer compatibility

Shade control is especially important when one order uses multiple fabric rolls. Even small differences between dye lots can become obvious when the front panel is cut from one roll and the back or sleeve comes from another.

Performance claims also need to be treated carefully. A fabric that feels dry or smooth in hand is not automatically moisture-wicking. When liquid moisture management is a defined requirement, buyers can reference AATCC TM195, which measures and classifies the liquid moisture management properties of textile fabrics.

The goal is not to test every possible property. It is to identify which properties matter for the intended running shirt and confirm them before the fabric has been cut into thousands of panels.

Step 5: Pattern Making, Sampling, and Size Grading

Once the fabric direction is clear, the factory develops the garment pattern.

The pattern controls the shape of the front, back, sleeves, neck opening, side panels, mesh inserts, and other garment components. It also determines how the shirt sits on the body and how it moves during running.

For a running T-shirt, important pattern areas include:

• Shoulder slope and shoulder width
• Armhole depth and shape
• Sleeve angle and opening
• Chest and waist allowance
• Front and back body length
• Neck width and neck drop
• Side seam balance
• Hem shape
• Placement of mesh or ventilation panels

A shirt can look correct on a table and still feel wrong during movement. The sleeve may pull when the arms swing. The body may ride up. The neck can feel too tight or become loose after washing. An athletic fit can become restrictive if the fabric stretch and pattern ease do not work together.

Sampling allows the factory and buyer to correct these issues before bulk production.

Depending on the complexity of the style, the approval process may include a development sample, fit sample, size set, print strike-off, and pre-production sample. Not every project requires the same number of rounds, but the final approved sample should reflect the intended bulk materials, fit, construction, logo method, labels, and finishing.

After the base size is approved, the pattern is graded into the full size range. Grading is not simply adding the same amount to every measurement. Chest, shoulder, armhole, sleeve, body length, and neck dimensions must grow in a balanced way.

This is why one approved medium-size sample is not always enough to confirm that an XS–3XL range will fit consistently.

For detailed measurement points, grading rules, and tolerance planning, use a dedicated running shirt size chart before approving the full size range.

Step 6: Fabric Relaxation, Spreading, Marker Making, and Cutting

Knitted fabric can change after it is unrolled. Tension from rolling and transportation may temporarily affect its length and width.

Before cutting, the factory may allow the fabric to relax according to the fabric type and production requirement. The fabric is then spread in layers on the cutting table.

A marker is created to arrange the pattern pieces efficiently across the fabric width. It normally includes front panels, back panels, sleeves, neckbands, side inserts, and any other cut components.

Marker efficiency affects material consumption and cost, but efficiency cannot come at the expense of fabric direction, stretch orientation, grain, print placement, or shade control.

After cutting, garment panels should be:

• Checked against the pattern
• Separated by size
• Numbered when necessary
• Bundled by garment or production batch
• Kept within the correct shade group

Bundling and numbering are easy to overlook, but they help prevent sleeves, bodies, or side panels from different sizes or fabric lots being mixed on the sewing line.

Lightweight running fabrics require careful handling. If the fabric is stretched during spreading or moves during cutting, the panels may return to a different shape later. That can cause twisting, mismatched seams, uneven hems, or measurement differences in the finished garment.

Step 7: T-Shirt Stitching Process and Garment Assembly

Sewing is the stage where the separate panels become a T-shirt.

A basic crew-neck T-shirt normally includes a front panel, back panel, two sleeves, and a neckband. Running T-shirts may add mesh panels, side inserts, vents, reflective tabs, bonded components, or shaped hems.

A typical T-shirt stitching process may look like this:

The exact sequence changes with the design. A raglan running shirt, a style with side mesh panels, and a simple set-in sleeve tee will not use exactly the same operations.

Stitch choice should match the fabric and use case.

Overlock construction is efficient and widely used. Coverstitch is commonly used for sleeve and bottom hems. Flat seams may reduce bulk in sensitive next-to-skin areas, but they require suitable equipment and careful tension control.

More stitching is not automatically better. The important issue is whether the seam is strong enough, flexible enough, visually clean, and comfortable during repeated arm movement.

Running fabrics can expose sewing problems quickly. Incorrect needle choice can damage lightweight fabric. Excessive thread tension can create puckering. Uneven feeding can make one panel longer than another. Deep or poorly placed underarm seams can become uncomfortable during long runs.

That is why sewing quality should be checked during production, not only after every shirt has been completed.

Step 8: Printing, Heat Transfer, Sublimation, and Labels

Printing is part of the manufacturing process, but it does not always happen at the same point.

Some artwork is applied to cut panels before sewing. Other logos are applied after the garment has been assembled. The correct order depends on the print method, artwork size, placement, fabric, and construction.

For a fuller comparison of screen printing, heat transfer, sublimation, and reflective applications, review the main sports T-shirt printing methods before approving the artwork.

For example:

• All-over sublimation is normally applied to polyester fabric or panels before final assembly.
• Screen printing may be applied to panels or finished garments, depending on the design.
• Heat-transfer and reflective logos are often applied after cutting or sewing.
• Neck labels may be printed directly, heat transferred, or sewn into the garment.
• Embroidery usually requires extra attention to backing, weight, and skin comfort.

For performance running shirts, appearance is only one part of logo approval.

Buyers should also consider:

• Flexibility when the fabric stretches
• Handfeel against the body
• Breathability under large graphics
• Adhesion after washing
• Cracking or edge lifting
• Color migration from polyester fabric
• Reflective placement and durability
• Alignment across different garment sizes

A large, heavy chest graphic can reduce the breathable area of an otherwise lightweight running tee. A reflective transfer may look correct before washing but lift at the edges if temperature, pressure, adhesive, or fabric finishing is not compatible.

The factory should therefore prepare a print strike-off or decorated sample using the intended fabric. Artwork approved on a computer screen is not enough to confirm physical color, scale, handfeel, stretch, or wash performance.

Step 9: T-Shirt Finishing Process and Quality Control

Quality control should run through the whole T-shirt production process.

Fabric is checked before cutting. Cut panels can be checked before sewing. Measurements and workmanship are reviewed during sewing. Print quality is checked during application. Final inspection then confirms the finished order.

After sewing and decoration, garments normally move through finishing operations such as:

• Loose-thread trimming
• Stain and oil-mark inspection
• Careful cleaning when required
• Pressing or steaming
• Measurement checking
• Final appearance inspection
• Folding, tagging, and size identification

Pressing should improve presentation without damaging heat-sensitive transfers, synthetic fabrics, reflective materials, or surface finishes.

Common final checks for custom running T-shirts include:

The checkpoints below summarize the most relevant T-shirt risks. Buyers who need a wider inspection framework can follow a complete garment quality control checklist for running apparel.

The factory should also distinguish between defects that can be repaired and problems that affect the whole order.

A loose thread can usually be corrected. A wrong neck opening, unstable bulk fabric, incorrect grading rule, or widespread print migration is much more serious because it may affect every garment.

This is why in-line control is valuable. It catches repeatable problems while production can still be adjusted.

Step 10: Packing and Shipment Preparation

Packing is the final stage, but it should not be treated as an afterthought.

By this point, the T-shirts should already be approved, finished, and inspected. The packing department then confirms how each garment is folded, labeled, bagged, grouped, and placed into cartons.

Packing requirements may include:

• Individual or bulk packing
• Size stickers
• Hangtags and barcode labels
• Branded or standard polybags
• Specific folding dimensions
• Carton size and weight limits
• Size or color assortment per carton
• Carton marks and purchase-order references
• Moisture protection when required

Errors at this stage do not necessarily affect garment quality, but they can still create serious downstream problems.

A retailer may receive the wrong size ratio. An event organizer may struggle to distribute shirts because the cartons are mixed. A warehouse may be unable to scan products because labels or barcodes are incorrect.

A clean T-shirt manufacturing process should end with an order that is easy to receive, count, sort, store, and distribute.

What Buyers Should Approve Before Bulk T-Shirt Production

A buyer does not need to supervise every factory operation. The buyer does need clear approval gates.

The pre-production sample is particularly important because it should represent what the factory plans to make in bulk.

If the final sample uses one fabric, one logo method, or one neckline construction while bulk production uses something different, the sample is no longer a reliable approval reference.

Any approved changes should also be recorded. Verbal instructions and scattered chat messages are difficult for multiple production departments to follow consistently.

Where Does the T-Shirt Manufacturing Process Usually Go Wrong?

T-shirt quality problems do not begin only at the sewing machine.

They can start when the product brief is incomplete, when the bulk fabric differs from the approved swatch, or when a print method is selected before compatibility is tested.

Common failure points include:

The approved sample and bulk fabric are not identical.
The composition may be the same, but the GSM, handfeel, shade, stretch, or finishing can still differ.

The pattern is approved in only one size.
The base size looks correct, but smaller or larger sizes develop neckline, armhole, sleeve, or length problems.

Fabric is cut before shrinkage and stability are confirmed.
The finished garments then move outside measurement tolerance after washing.

Printing is approved only by artwork file.
The physical result may feel too stiff, show color migration, or crack after stretching.

Quality control begins too late.
A repeated sewing or measurement problem is discovered only after the full quantity has been completed.

The purpose of understanding the manufacturing process is not to remove every possible risk. It is to move the important decisions earlier, when corrections are still practical.

What This Process Means for Running Apparel Buyers

A running T-shirt is not simply a standard cotton tee made with polyester.

The production steps may look similar, but the approval priorities are different.

A running shirt must remain comfortable when the wearer is moving and sweating. It needs a pattern that supports arm swing, a fabric that manages heat and moisture appropriately, seams that do not create unnecessary friction, and logos that do not undermine stretch or breathability.

That makes the full production chain important:

• Yarn and knitting influence surface, stretch, and airflow.
• Dyeing and finishing influence shade, handfeel, stability, and moisture behavior.
• Pattern development influences movement and fit.
• Cutting influences symmetry and garment balance.
• Sewing influences comfort and durability.
• Printing influences appearance, flexibility, and breathability.
• Quality control influences bulk consistency and reorder reliability.

For B2B buyers, the most useful question is not simply, “Can this factory make T-shirts?”

A better question is:

Can the manufacturer control the material, fit, construction, decoration, approvals, and quality checks required for this specific running T-shirt program?

That is where two visually similar shirts can follow very different production paths.

FAQ

How are T-shirts manufactured step by step?

T-shirts are manufactured through product planning, fabric development, knitting, dyeing and finishing, pattern making, sampling, grading, fabric spreading, cutting, sewing, printing, garment finishing, quality inspection, packing, and shipment preparation. Custom running T-shirts also require checks for moisture behavior, stretch, fit, seam comfort, and logo compatibility.

How are custom T-shirts made?

Custom T-shirts can be made by decorating existing blank garments or through full cut-and-sew production. Blank decoration adds printing, labels, or packaging to a finished shirt. Cut-and-sew production develops the fabric, pattern, fit, construction, branding, and packaging specifically for the buyer.

Are all T-shirt production steps completed in one factory?

Not necessarily. A garment manufacturer may coordinate textile mills, dye houses, print suppliers, trim suppliers, and testing laboratories. What matters is whether the manufacturer controls the approved specifications, material lots, sample references, production quality, and final delivery.

What machines are used to manufacture T-shirts?

Common equipment includes circular knitting machines, fabric inspection machines, spreading and cutting equipment, overlock machines, lockstitch machines, coverstitch machines, flatseam equipment, heat presses, screen-printing equipment, and pressing or finishing equipment. The exact machines depend on the fabric, design, seam construction, and logo method.

Is T-shirt printing done before or after sewing?

It can be done either before or after sewing. Sublimation and some large panel prints are commonly completed before garment assembly. Heat-transfer logos, reflective details, direct neck labels, and some screen prints may be applied after the panels are cut or after the T-shirt is sewn. The correct stage depends on the artwork and construction.

How long does T-shirt manufacturing take?

The full timeline depends on whether the project uses existing fabric or custom-developed material, how many sample rounds are required, the printing method, order quantity, testing requirements, and material availability. Buyers should separate fabric sourcing, sampling and approval time from the actual bulk cutting and sewing period.

For order planning by customization level, sampling requirements, and bulk quantity, see our custom running apparel MOQ and lead time guide.

Why do similar T-shirts receive different factory quotes?

Two T-shirts can look similar while using different yarns, fabric weights, finishes, patterns, seams, logo methods, labels, testing requirements, and QC standards. The quote reflects the complete production specification, not only the visible design.

Start with a Clear Manufacturing Brief

If your brand is developing custom running T-shirts, race tees, run-club shirts, or lightweight performance tops, begin with the intended use, target fit, fabric direction, size range, artwork, order quantity, and quality expectations.

Diguan can use these details to review the fabric, pattern, construction, logo method, and production path before bulk manufacturing begins.

A reference sample, tech pack, measurement chart, or even a well-organized product brief gives the factory a much stronger starting point than product photos alone.