Sourcing Best Practices: Fabric & Raw Material Sourcing

Fabric accounts for 45–65% of a textile FOB price and is simultaneously the most common source of quality failures — because fabric substitution (a factory sourcing an 'equivalent' from a different mill when the specified fabric is out of stock) changes GSM, hand, colour consistency and shrinkage performance without the buyer's knowledge. Three best practices prevent it: naming the approved fabric mill in the purchase order, requiring pre-production fabric testing (GSM, colour fastness, dimensional stability, tensile strength) before cutting is authorised, and specifying that any mill substitution requires explicit buyer approval and a new lab dip before bulk fabric enters the cutting room.

Best Practice 1: Specify Fabric Mill and Grade

The most effective prevention for fabric substitution is naming the approved fabric mill in the purchase order or Tech Pack. Once a fabric is tested, approved and costed from a specific mill, any substitution should require explicit buyer approval — not a factory decision. Where a specific mill cannot be named at the outset, specify that any fabric substitution requires a new lab dip and fabric test before cutting begins.

Best Practice 2: Require Pre-Production Fabric Testing

Do not wait until after the product is sewn to discover that the bulk fabric does not meet specification. Require pre-production fabric testing — an independent lab test of the bulk fabric roll from the same dye lot that will be cut — before cutting authorisation is given.

Best Practice 3: Manage Dye Lot Consistency

In a long production run, multiple dye lots of the same fabric colour will be used. Colour can vary between dye lots even when all lots are within tolerance individually — a phenomenon called metamerism (the lots match under D65 but not under incandescent light) or shade banding (lots shade from batch to batch). Best practices:

• Require lot segregation: each dye lot is kept separate in the warehouse and cut and packed separately — not mixed within a single carton or garment.
• Request dye lot approval before each new lot is cut: each new lab dip is approved against the original standard.
• Specify a DE limit: the maximum acceptable colour difference between any two dye lots is defined numerically (e.g. ≤1.0 DE CMC between adjacent lots).

Best Practice 4: For Certified Content, Secure Transaction Certificates

If the product specification requires certified fibre (GOTS organic, GRS recycled, BCI), the certification must flow through the fabric procurement — not just the finished product. The fabric mill must hold a current Scope Certificate, and a Transaction Certificate (TC) must be issued for each lot of certified fabric supplied to the factory. Without TCs, the finished product cannot legitimately claim certification.

Best Practice 5: Maintain a Fabric Reference Library

For repeat or seasonal programs, maintain a sealed fabric reference library — a 10×10cm sealed swatch of every approved fabric per style, with the mill name, fabric reference, lot number, GSM test result and approval date attached. This provides a physical reference for every future re-order and makes substitution instantly visible at incoming inspection.

To specify certified or verified raw materials for your programme, submit your fabric requirements and annual volume in the sourcing RFQ form — we return mill options with current certification scope certificates and pre-production fabric test reports included.