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Reference · Manufacturing7 min · 1,436 words

Term entry

Overlock Stitch

A looped stitch produced by an overlocker/serger machine that simultaneously trims, encloses, and finishes fabric edges,the global industrial sewing machine market is valued at $5.8 billion (₹527.8 billion) in 2025, with overlockers representing 25–30% of all machine sales.

7 min read1,436 wordsSearch volume · 1–5K/moUpdated · February 2026
Overview · 01

What is Overlock Stitch?

Overlock stitch (also called serger stitch) is produced by an overlocker or serger machine,a specialized industrial sewing machine that simultaneously performs three operations: trims excess fabric from the seam allowance, encloses the raw fabric edge in loops of thread, and stitches the seam. The result is a clean, stretch-resistant seam finish that prevents fraying.

Unlike a conventional sewing machine that uses a single needle and bobbin, an overlocker uses 3, 4, or 5 threads from spools (called a 3-thread, 4-thread, or 5-thread overlock), passing through loopers above and below the fabric to create the characteristic wrapped-edge appearance.

Common overlock configurations:

3-thread overlock:

  • Used for finishing single raw edges (not joining two layers)
  • Wraps the edge in a loose, stretchy loop; ideal for knit hems and single-layer edge finishing
  • Very efficient; fastest overlock operation

4-thread overlock (safety stitch):

  • Combines a chain stitch (for seam strength) with an overlock edge finish
  • Most common in garment production for joining and finishing seams simultaneously
  • Strong and flexible; used extensively in t-shirts, casualwear, and knit garments

5-thread overlock:

  • Combines two-needle chain stitch with three-thread overlock
  • Maximum seam strength; used in demanding applications (activewear, jeans outseams, workwear)

Flatlocking:

  • A specialty overlock technique where the seam is opened flat after sewing, creating a decorative visible seam on the right side
  • Used in activewear, athleisure, and technical garments; also decorative in womenswear

Mock flatlocking / cover stitch:

  • Technically a separate machine operation but related; used for hems in knit garments to create the clean, two-row top-stitch visible on T-shirt necklines and sleeve hems
Entrepreneur's perspective · 02

Why this matters for fashion entrepreneurs.

Overlock stitch quality directly impacts garment durability and perceived value,85%+ of all garment seams worldwide use some form of overlock finishing. The global industrial sewing machine market ($5.8 billion in 2025) sees overlockers as the second most-purchased machine type after lockstitch.

Overlock machine cost comparison (global):

Machine BrandTypeUSA PriceUK PriceIndia PriceSpeed (SPM)
Juki MO-68005-thread$1,200–$2,500 (₹109,200–₹227,500)£900–£1,800₹45,000–₹120,0007,000
Brother N-314-thread$800–$1,800 (₹72,800–₹163,800)£600–£1,400₹35,000–₹85,0006,500
Pegasus M7005-thread$1,500–$3,000 (₹136,500–₹273,000)£1,100–£2,200₹55,000–₹130,0007,500
Usha/Singer3-thread$200–$450 (₹18,200–₹40,950)£150–£350₹15,000–₹35,0004,500

Quality indicators for brand founders:

  • Stitch density: 12–15 SPI (stitches per inch) standard; too loose = unprofessional gaps; too tight = stiffness
  • Thread tension: Even tension on all looper/needle threads; tension problems appear as twisted seams or puckering
  • Seam width: 5–6mm standard; 3–4mm for lightweight fabrics; 7–8mm for denim/heavy garments
  • ASTM codes for tech packs: 504 (3-thread overlock), 514 (4-thread safety), 516 (5-thread safety)

ROI insight: Investing in quality overlock equipment ($1,200–$3,000 / ₹109,200–₹273,000) versus budget machines ($200–$450 / ₹18,200–₹40,950) reduces rework by 40–60% and increases production speed by 25–35%,typically paying for itself within 6–12 months.

Sourcing guide · 03

Where to source.

Global overlock machine and thread sourcing comparison:

SourceMachines AvailableThread BrandsBest For
USA (?"Seattle Fabrics, Sewingmachinesplus)Juki, Brother, BabylockCoats & Clark, Gutermann$800–$3,000 retail, fast delivery
UK (Sewingcraft, Franklins)Juki, Brother, JanomeCoats, Madeira£600–£2,200, EU warranty
Japan (direct Juki/Pegasus)OEM industrial machinesFujixPremium quality, bulk orders
India (Delhi, Mumbai dealers)Juki, Brother, Pegasus, UshaCoats India, Madura Coats₹15,000–₹130,000, local support
China (Alibaba, Jack)Jack, Siruba, TypicalEconomy brands$300–$1,200, high volume

Overlock thread specifications:

  • Standard weight: 120/2 or 150/2 polyester or corespun (cotton-core poly)
  • Cone sizes: 5,000–10,000 meters for industrial use
  • Coats Dual Duty: $3–$5/cone (₹273–₹455),industry standard worldwide
  • Economy thread: $1–$2/cone (₹91–₹182),acceptable for basic garments
  • A basic T-shirt uses 80–120 meters of overlock thread across all seams

Maintenance essentials: Overlock machines require cleaning (lint removal), oiling, and blade replacement every 3–6 months. Budget $50–$100 (₹4,550–₹9,100) per service in USA/UK, ₹2,000–₹6,000 ($22–$66) in India. Ask factories for their maintenance log during audits.

Pricing & costs · 04

What it costs.

Overlock stitch cost breakdown,global comparison:

Cost ComponentUSAUKEUIndia
Machine (industrial 4-thread)$800–$2,500 (₹72,800–₹227,500)£600–£1,800€700–€2,200₹35,000–₹85,000 ($385–$934)
Machine (industrial 5-thread)$1,200–$3,000 (₹109,200–₹273,000)£900–£2,200€1,000–€2,800₹45,000–₹130,000 ($495–$1,429)
Used industrial overlocker$400–$1,200 (₹36,400–₹109,200)£300–£900€350–€1,000₹12,000–₹45,000 ($132–$495)
Thread (per 5,000m cone)$3–$5 (₹273–₹455)£2–£4€2.50–€4.50₹40–₹90 ($0.44–$0.99)
Service/maintenance$50–$100 (₹4,550–₹9,100)£40–£80€45–€90₹2,000–₹6,000 ($22–$66)
Operator wage (monthly)$2,800–$4,200 (₹254,800–₹382,200)£1,800–£2,600€2,000–€3,000₹12,000–₹20,000 ($132–$220)

Per-garment overlock cost analysis:

  • Thread cost per T-shirt: $0.02–$0.04 (₹1.82–₹3.64) in USA; ₹0.64–₹0.96 ($0.007–$0.011) in India
  • Per-seam operation cost: $0.15–$0.50 (₹13.65–₹45.50) USA; ₹2–₹8 ($0.02–$0.09) India
  • Overlock/seaming represents 35–55% of total CMT (Cut, Make, Trim) cost globally
FAQ · 08

Frequently asked.

They are the same thing,different terminology for identical stitching. "Overlock stitch" is the industrial manufacturing term used globally; "serger stitch" is the home sewing term common in the USA. Both refer to the looped, edge-enclosing stitch produced by an overlocker/serger machine that trims, encloses, and finishes fabric edges simultaneously. Industrial overlockers ($800–$3,000 / ₹72,800–₹273,000) operate at 6,000–7,500 SPM versus home sergers ($200–$800 / ₹18,200–₹72,800) at 1,200–1,500 SPM.

Industrial overlock machine prices vary by brand and configuration. A 4-thread Juki or Brother costs $800–$2,500 (₹72,800–₹227,500) in the USA, £600–£1,800 in the UK, and ₹35,000–₹85,000 in India. Premium 5-thread models (Pegasus, Juki MO-6800) cost $1,200–$3,000 (₹109,200–₹273,000). Used industrial overlockers start at $400 (₹36,400) in the USA and ₹12,000 in India. Chinese brands like Jack and Siruba offer budget options at $300–$1,200 (₹27,300–₹109,200) with comparable functionality.

A 3-thread overlock (ASTM 504) finishes single raw edges only,used for hem finishing and lightweight seaming. A 4-thread overlock/safety stitch (ASTM 514) combines chain stitch + overlock for simultaneous seaming and edge finishing,the most common in garment production for T-shirts and casualwear. A 5-thread overlock (ASTM 516) adds a two-needle chain stitch with three-thread overlock for maximum strength,used in activewear, jeans outseams, and workwear where seam failure is unacceptable.

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