Short answer: pants go wrong mostly on fit, so the work is in the specification. Choose a factory that makes your type of pants (knit pants such as joggers, lounge or yoga pants are usually made in different factories from woven chinos or jeans), fix every point of measure with a tolerance, approve fit on a real person through a set sequence of samples, and write the waistband, pockets, trims and tests into the order before bulk starts.
For the pants styles factories commonly offer, see what custom pants a wholesale manufacturer can supply and men’s pants fit types. This page is about the production process.
Knit or woven: pick the right kind of factory
| Point | Knit pants (joggers, lounge, yoga, leggings) | Woven pants (chinos, trousers, jeans) |
|---|---|---|
| Typical machines | Overlock, coverstitch, flatlock | Lockstitch, felling, bartack, buttonhole; washing for denim |
| Fit relies on | Fabric stretch and recovery; negative ease in leggings | Pattern shape and ease; little stretch unless elastane is added |
| Typical trims | Elastic, drawcord, eyelets | Zips, buttons, rivets, interlining |
| Key fabric checks | Stretch and recovery, pilling, shrinkage | Seam slippage, shrinkage, colour fastness to rubbing on dark shades |
Points of measure to fix in the tech pack
- Waist: relaxed and, for elastic waists, extended.
- Hip or seat, measured at a stated distance from the waist.
- Front rise and back rise.
- Thigh, knee and leg opening, each at a stated position.
- Inseam and outseam.
- Waistband height, pocket size and position.
Give a tolerance for each point and say how it is measured; if you do not, the factory’s house tolerances apply. For leggings and yoga pants see negative ease per size and yoga pants length.
The sample sequence
- Proto sample to check construction and look.
- Fit sample in your base size, tried on a fit model who sits, squats and walks; check the rise and seat first.
- Size set to check grading across the range. See when the medium fits but the XL does not.
- Pre-production sample in bulk fabric and trims, then a sealed sample. See what a sealed sample record should include.
Construction and trims to specify
- Waistband: elastic type and width, casing or attached, drawcord and eyelets.
- Crotch and stress points: seam type and where bartacks go.
- Pockets: type, depth and any phone pocket. See phone pocket position.
- Hems or cuffs, label positions, and for wovens the zip, button and rivet specification.
Tests worth asking for
- Shrinkage by a named method (AATCC TM135, or ISO 6330 with ISO 5077).
- Knit stretch and recovery (for example ASTM D2594 for low-power knits) and pilling (ISO 12945-2).
- Colour fastness to rubbing (ISO 105-X12), important for dark pants that touch light seats and bags.
- For woven pants, seam slippage at stress seams (ISO 13936-1, which does not apply to stretch fabrics).
Fact, recommendation, uncertainty
Fact: pants sold in the U.S. need fibre content (16 CFR Part 303), care instructions (16 CFR Part 423) and country of origin on the label. Recommendation: approve fit on a person, not on a table measurement alone, and agree the inspection plan (for example ISO 2859-1) before bulk. Uncertainty: minimums and lead times depend mainly on fabric minimums per colour and the number of sampling rounds; ask each factory for its own figures. See minimum per colour.
Where Knitwear Base fits
Knitwear Base works in knit categories; for knit bottoms see our loungewear and yoga clothing pages. For woven chinos or jeans, look for a woven specialist. Questions about a knit pants program can go through the contact page.
Sources and further reading
- ISO 8559-1:2017, Size designation of clothes: anthropometric definitions for body measurement
- AATCC TM135, Dimensional Changes of Fabrics after Home Laundering
- ISO 6330:2021, Domestic washing and drying procedures for textile testing
- ISO 5077:2007, Determination of dimensional change in washing and drying
- ASTM D2594/D2594M, Stretch Properties of Knitted Fabrics Having Low Power
- ISO 12945-2:2020, Fabric propensity to surface pilling, fuzzing or matting: modified Martindale method
- ISO 105-X12:2016, Colour fastness to rubbing
- ISO 13936-1:2004, Slippage resistance of yarns at a seam in woven fabrics: fixed seam opening method
- eCFR, 16 CFR Part 303, Rules under the Textile Fiber Products Identification Act
- eCFR, 16 CFR Part 423, Care Labeling of Textile Wearing Apparel
- ISO 2859-1:2026, Sampling procedures for inspection by attributes (AQL)
Rules and standards are summarised from their official pages for general guidance; this is not legal advice. Check the current version and the requirements of your own market before you rely on them.
