Seamless underwear, your specification
Made to your tech pack, fabric and colours by a factory matched to the order.
Private label
Your main label, care label, hangtag and polybag. Nominated trims accepted.
Seamless underwear is knitted, not cut: a circular machine knits each garment body as a tube close to its final shape, with rib, mesh and plain zones built into the knit. Only the crotch or the top is closed afterwards. Brands buy it for men's trunks, women's briefs, bralettes and light shaping pieces with no side seams. A seamless underwear manufacturer in Bangladesh usually knits nylon elastane and garment dyes the finished bodies.
The first question on a seamless enquiry is the machine, so Garments Hub BD asks each factory to state the machine diameter and gauge it will knit on, next to its price. If no factory on the bench can knit your construction, you get a straight no rather than a cut and sew substitute sold as seamless. Your tech pack and knit files are used for this order only.
Kinds of seamless underwear
Seamless trunks and boxer briefs
Men's styles knitted with a shaped pouch zone, a rib or jacquard waistband knitted in, and a short leg. The logo can be knitted into the band instead of woven into a separate elastic.
Seamless briefs and hipsters
Women's bottoms knitted with a welt at waist and leg, so there is no elastic to sew. The gusset is a separate piece sewn or bonded in, the one seam most seamless briefs keep.
Seamless bralettes and crop tops
Knitted with denser zones under the bust and a pocket for removable pads. Pull on and wire free; support comes from the knit structure and the elastane share, not from cups or wires.
Light shapewear
Briefs, shorts and camisoles with firmer knitted panels at the tummy or waist. The shaping comes from denser knit and more elastane, so any shaping claim is the buyer's own wording.
How to brief a seamless underwear manufacturer in Bangladesh
- Machine diameter and gauge
- Body diameter typically 12 to 16 inches for underwear, and gauge usually 24 to 32 needles per inch. Your sizes have to fit the diameters the plant runs.
- Yarn and elastane share
- Nylon with covered elastane, usually 8 to 20 percent elastane, or a cotton nylon mix for a softer face. Name the denier if you have a reference garment.
- Sizes per tube
- One diameter usually stretches across one or two sizes, so seamless ranges run S/M and L/XL, or one size, more often than a five size grid. Decide the split first.
- Knitted zones
- Mark rib, mesh, jacquard and plain areas on the sketch with measurements. Each zone is programmed into the knit, and changing it after sampling means a new programme.
- Waist and leg finish
- A double welt knitted in, or a bonded band added after knitting. The knitted welt is softer and costs less; bonding gives a flatter edge.
- Dyeing
- Bodies are usually knitted in white yarn and garment dyed after closing. Give the shade and the light source, and expect small variation between dye batches.
Tests for seamless knitted underwear
- EN 12127
- Mass per unit area from small samples, which suits a knitted body that has no length of flat fabric to cut. Use it to confirm each zone stays at the agreed weight.
- ISO 13938
- Bursting strength of knit fabric. On a fine gauge seamless body it shows whether the mesh zones and the thinnest areas hold under stretch.
- ISO 105-C06
- Colour fastness to washing for garment dyed nylon, graded 1 to 5. Dark shades on nylon elastane can stain lighter pieces in the same wash, so ask for the staining result too.
What moves the price of seamless underwear
- Knitting time per body: more zones and jacquard patterns slow the machine.
- Yarn denier and elastane share, since finer nylon and more elastane cost more per kilo.
- Number of tube diameters, each one a separate machine set up.
- Garment dyeing and the shade count, run in batches after knitting.
- Sewing or bonding after the knit: gusset, crotch closure and any bonded band.
Lead time for seamless underwear
Seamless follows the bench timing of 7 to 14 days for samples and 30 to 60 days for bulk after PP approval, but the first sample waits for the knit programme to be written. A new jacquard logo or zone layout adds days at proto stage. Garment dyeing runs after knitting, so each extra shade adds a batch. The quote gives the confirmed dates.
What we check on seamless underwear before shipment
- Measurements after dyeingWidth and length measured on dyed and boarded bodies, since dyeing and heat setting change the final size of nylon elastane.
- Dropped stitches and laddersEach body checked against light for dropped stitches, holes and ladders, which run quickly in fine nylon.
- Welt rollWaist and leg welts lie flat on the form and do not roll after stretching and release.
- Zone placementRib and mesh zones sit where the sketch puts them on every size, with no drift between machines.
Questions buyers ask about seamless underwear
How many sizes can a seamless range carry?
Fewer than cut and sew. Each machine diameter covers one or two sizes through stretch, so most seamless ranges run two or three sizes, or one size. A five size grid is possible only where the plant has enough diameters, and each one is a separate set up.
Is seamless knitting cheaper than cut and sew underwear?
Not usually per piece. The machine is slower than a cutting table, and nylon elastane yarn costs more than cotton jersey. Seamless saves sewing operations and fabric waste, which helps on complex shapewear more than on a plain brief.
Can seamless underwear be made in cotton?
Partly. Cotton or cotton nylon yarns can be knitted on seamless machines, usually with nylon and elastane carrying the stretch. A full cotton face with the recovery of nylon is harder; ask for a knitted swatch before committing a range to cotton.
What should we ask a factory before sending a seamless design?
Ask for the diameters and gauges the plant runs, whether it dyes and boards in its own building or sends out, and a body it has knitted in a similar yarn. Those three answers decide your sizes, your shades and your lead time.
Get a quote for seamless underwear
Tech pack or sketch with quantities per colour. A compared quote in 48 hours.
