Quality

Sock Pre-Shipment Inspection Booking Guide

Published: 2026-07-10By ZheSock TeamReading time: 10 min

A sock pre-shipment inspection should be booked before the shipping date starts to squeeze you. If cartons are sealed one day before container loading, a small defect can become repacking work, missed vessel space, or air freight. For a basic cotton crew sock order, one inspection day at USD 180 to USD 320 is far cheaper than relabeling 20,000 polybags after the goods reach a retail warehouse. This guide explains when to book, what to send, how many pairs to sample, what acceptance criteria to set, how to approve samples before bulk production, and what to do when the report fails.

Table of Contents

1. When should you book a sock pre-shipment inspection?
2. What production stage is right for inspection?
3. How many pairs should the inspector check?
4. What should be on a sock inspection checklist?
5. Who books the inspection and who pays?
6. How do you handle a failed inspection?

When should you book a sock pre-shipment inspection?

Book the sock pre-shipment inspection when at least 80 percent of the order is finished and at least 80 percent is packed in export cartons. Finished means knitted, toe closed, washed or dyed if needed, boarded, paired, labeled, and packed in the buyer's shipping format. For most sock orders, send the booking request 7 days before the target inspection date.

Work backward from the ex-factory date. If the planned ex-factory date is June 20, set inspection for June 15 or June 16. That leaves 2 to 4 days for sorting, reboarding, label changes, carton remarking, or short quantity replacement. Do not book inspection on the same day as container loading. That is gambling.

Peak booking periods in China are usually March to May and September to November. During those months, book 10 to 14 days ahead if you use a third-party inspection company. A standard one-man-day inspection in China often costs USD 180 to USD 320. Remote factory locations, same-week booking, or weekend work can add USD 50 to USD 150 in travel or urgent fees.

Ask the factory for a packing report once 60 percent of the pairs are completed. For a 20,000 pair order, request the first report when about 12,000 pairs are packed. The report should show style, color, size, packed pairs, remaining pairs, carton count, carton number range, storage location, and estimated finish date.

Add a booking hold point to the purchase order. State that final inspection can start only after the factory confirms the packed percentage in writing and sends clear photos of packed cartons, retail packing, carton marks, and the approved sample on site. If the factory delays this confirmation, keep 1 extra day in the shipping plan. A cheap inspection loses value if the inspector arrives before goods are ready.

What production stage is right for inspection?

The right stage is final random inspection of finished goods. Raw yarn checks and inline patrols help, but they do not replace final inspection. Some sock defects only show after boarding or washing. Examples include size shrinkage, twisted leg panels, weak welt recovery, toe seam ridges, oil stains, and shade difference between pairs.

The inspector should check goods in the buyer's packing format. If the order ships as 3 pairs per header card, the sampled goods should already be on the header card. If the order ships in retail polybags with UPC labels, the barcodes must be printed and applied before inspection. Bulk pairs loose in baskets are not ready for final random inspection.

Check purchase order quantity against the factory packing list and packed carton count.
Select cartons from the front, middle, back, top, and bottom of the packed area where access allows.
Open cartons chosen by the inspector, not cartons prepared by the factory.
Measure foot length, leg length, cuff height, and stretch against the approved size spec.
Scan EAN or UPC codes from each style, color, and size.
Check carton marks, carton dimensions, gross weight, net weight, carton strength, and carton sealing method.
Compare the retail packing to the signed pre-production sample or sealed approval sample.

If less than 80 percent is packed, state that in the report. The uninspected balance may come from another knitting line, another dye lot, or a later packing shift. That risk is real.

For split shipments, inspect each shipment as its own lot unless the buyer accepts a written exception. If 12,000 pairs ship in June and 8,000 pairs ship in July, the July goods need their own packing and quality check. Old results should not be used for new production.

Sample approval should happen before this stage. The buyer should approve a fit sample, artwork sample, and packing sample before bulk knitting starts. For color sensitive orders, approve a lab dip or yarn color reference before yarn purchase. For size sensitive orders, approve a pre-production pair after washing and boarding. Keep one approved sample at the factory and one with the buyer or inspection company. The inspector should use the factory retained sample during the final check.

How many pairs should the inspector check?

Most importers use ANSI or ISO 2859 AQL sampling for socks. A common setting is General Inspection Level II, AQL 2.5 for major defects, AQL 4.0 for minor defects, and zero tolerance for critical defects. Critical defects include metal contamination, mold, sharp objects, wrong fiber claim, missing safety warning where required, and mixed customer goods.

For an order of 10,000 pairs under General Level II, the sample size is usually 200 pairs. Under AQL 2.5, the lot passes major defects at 10 or fewer and fails at 11. Under AQL 4.0, it passes minor defects at 14 or fewer and fails at 15. For a 20,000 pair order, the sample is often 315 pairs. At AQL 2.5, 14 major defects can pass and 15 fails. At AQL 4.0, 21 minor defects can pass and 22 fails.

Sampling must cover the full order mix. If the order has 4 colors and 5 sizes, the inspector should draw from all 20 combinations where stock exists. Do not let all samples come from black size M. For a small trial run, such as a 100 to 500 pair MOQ development order, AQL may be too loose. In that case, use 100 percent checking or inspect at least 50 percent of the pairs.

Set acceptance criteria before booking. A practical defect split is simple. Critical defects are not accepted. Major defects affect sale, wear, safety, size, fiber claim, barcode use, or customer complaint risk. Minor defects are small appearance issues that do not affect use. The report should not leave defect grading to guesswork.

Critical: needle or metal piece inside the sock, mold smell, wrong fiber content claim, mixed customer brand, missing choking warning where required, or unsafe sharp packing item.
Major: hole, broken yarn, open toe seam, wrong size label, wrong barcode, missing pair, wrong color in carton, foot length outside tolerance, or logo in the wrong position by more than the approved limit.
Minor: loose thread under the stated limit, light crease after boarding, slight yarn slub, small shade variation inside approved range, or carton mark smudge that is still readable.

For orders above 50,000 pairs, add a packing audit. Scan at least 5 barcodes per SKU, weigh at least 10 cartons, and open cartons from at least 3 pallet or storage positions. Packing errors spread fast when one label roll or carton mark file is wrong.

There is a commercial trade-off. AQL 1.5 for major defects gives tighter control, but it raises inspection time and failure risk. AQL 4.0 for major defects may reduce delays, but it pushes more complaint risk to the buyer. For a discount bulk sock program, AQL 2.5 major and 4.0 minor is common. For premium retail, baby socks, compression socks, or licensed logo socks, many buyers use stricter limits and add extra checks on size, claims, and artwork.

What should be on a sock inspection checklist?

A sock quality control checklist must match the product type. A 200 needle dress sock, a 144 needle terry sport sock, and a 96 needle heavy boot sock do not use the same tolerance. Put the approved sample, tech pack, size chart, yarn composition, artwork, and packing file in the booking email before the inspector arrives.

Record machine and construction details where available. Common needle counts include 96N for thick winter socks, 120N to 144N for sport socks, 168N for fine casual socks, and 200N for fine dress socks. If the buyer controls fabric mass, state the method. Socks are usually checked by grams per pair, such as 28 to 35 g per pair for light crew socks and 55 to 80 g per pair for thick terry crew socks. If GSM is used for a terry panel test, write the cutting area and target, for example 280 to 420 GSM, so the factory and inspector use the same method.

Construction: needle count, knit gauge, rib type, terry position, toe closure, heel shape, cuff height, foot length, and leg length.
Workmanship: dropped stitches, needle lines, holes, loose yarn, thick knots, oil marks, dirty marks, poor toe closure, and uneven boarding.
Fit checks: welt stretch, recovery after stretch, pair matching, left and right shape where applicable, and size tolerance.
Appearance: logo position, jacquard clarity, embroidery thread ends, print cracking, shade difference, and color matching to approved sample.
Packing: hangtag, header card, UPC or EAN barcode, polybag warning text, carton marks, carton size, carton weight, and pair count per carton.
Documents: purchase order, packing list, fiber content, care label file, and buyer requests for OEKO-TEX, GOTS, GRS, ISO 9001, BSCI, Sedex, or CE where relevant.

Size tolerance should be written in numbers. For many adult socks, buyers use plus or minus 0.5 cm for foot length and plus or minus 1.0 cm for leg length. For children's socks, many buyers use plus or minus 0.3 cm to 0.5 cm for foot length because size jumps are smaller. For compression socks, tolerance must be tighter and pressure testing should be arranged before bulk shipment. A final visual check is not enough for compression claims.

Add sample approval steps to the checklist. The signed pre-production sample should show yarn color, logo execution, welt height, foot length, leg length, toe seam feel, washing result, board shape, and packing format. If the buyer approves by photo only, write that photo approval does not approve hand feel, stretch, or exact shade. For important programs, courier one physical sample before bulk.

For packing, check both retail and export packing. Count pairs per polybag, pairs per inner box if used, inners per carton, and total pairs per carton. Scan barcodes with a real scanner or mobile scan tool and compare the number to the buyer's SKU list. Check that suffocation warning text, recycling mark, size sticker, color name, and country of origin match the buyer file where these items are required.

Carton checks matter. Measure at least 3 cartons for length, width, and height. Weigh at least 3 cartons per main packing method, or more for large orders. Compare gross weight and net weight to the packing list. Check tape quality, strapping if used, carton burst risk, wet cartons, crushed corners, and mixed carton numbers. Weak cartons can turn a passed product into a warehouse claim.

Who books the inspection and who pays?

The buyer usually books and pays the third-party sock inspection company because the report must go straight to the buyer. Some importers let the factory book, but that lowers control. If the factory pays, the buyer should still choose the inspection company, approve the checklist, and receive the report first.

Put the inspection rule in the purchase order before deposit. A clear term is simple: final balance is paid after passed inspection and correct shipping documents. If failure is caused by workmanship, wrong quantity, wrong packing, or missing labels, the factory pays the re-inspection fee. If the buyer changes artwork or packing after production, the buyer pays for the extra inspection.

The factory must prepare the site. They should provide open access to packed cartons, 2 workers for carton moving, a clean measuring table, a calibrated scale, a barcode scanner if needed, enough light, and the approved sample. Cartons should not be buried under other orders. If cartons are palletized, the inspector still needs random access. That may mean cutting stretch film and rebuilding pallets after the check.

For ZheSock orders in Datang, Zhejiang, common production lead times are 7 to 12 days for sample socks after artwork approval and 25 to 40 days for bulk orders after deposit, yarn confirmation, and packaging approval. Low MOQ development runs can start from 100 pairs per design. Many private label bulk orders work better at 1,000 to 3,000 pairs per color. Plan inspection inside that calendar, not as an afterthought.

State the release rule in commercial terms. Some buyers release shipment only after a pass report. Others allow shipment with minor defects below AQL if the factory gives a credit note, replacement pairs, or free spare labels. Do not leave this to a late phone call. Write who can approve a waiver, what value cap applies, and whether the waiver affects future orders.

Payment timing changes risk. A 30 percent deposit and 70 percent balance after passed inspection gives the buyer more control than full payment before inspection. Letter of credit terms can also require a passed inspection certificate, but banks check documents, not sock quality. For small orders, the cost of strict controls may be higher than the risk. For retail launch orders, the inspection cost is usually cheap insurance.

How do you handle a failed inspection?

Do not reject or release the shipment from the pass or fail line alone. Read the defect table. A wrong carton mark and a needle hole near the toe do not carry the same risk. Ask the inspector to break defects down by style, size, color, and carton number. Photos should include a ruler or label when size, logo position, or barcode data is involved.

Sort defects into five actions: accept, repair, replace, rework packing, or reject. Minor loose threads can often be trimmed. Wrong barcode stickers on 20,000 polybags may take 1 to 2 days with 4 workers if correct labels are ready. Reboarding 10,000 to 30,000 pairs usually takes 2 to 3 days if forms and steam equipment are available. Re-knitting missing or defective pairs can take 5 to 10 days, and longer for 200N fine gauge socks or jacquard patterns with several yarn colors.

Use a containment plan. The factory should separate failed cartons from passed cartons, mark the hold area, and keep a count sheet for repaired goods. If the defect is linked to one knitting machine, one toe closing operator, one dye lot, or one packing table, isolate that batch first. Then check nearby batches. Do not mix repaired pairs back into bulk stock without a recount.

After correction, book re-inspection. The scope should cover the failed points plus random checks from the full order. If the first failure was wrong size ratio in cartons, do not only inspect the relabeled cartons. Recount carton quantities and scan barcodes again. If the failure was poor toe closure, pull samples from several production batches, not just the repaired batch.

Keep the corrective action written. The factory should send photos of sorted defects, repaired goods, new labels, updated carton marks, and repacked cartons before the inspector returns. ZheSock has 17 years of sock export work, and this written step still prevents arguments. It gives both sides a clear release record.

Decide the commercial path with numbers. If 18 major defects appear in a 315 pair sample, the lot fails under AQL 2.5. The buyer may require full sorting, re-inspection, and shipment delay. If only 2 extra minor defects exceed the limit and the product is not for a strict retailer, the buyer may accept with a discount, extra spare pairs, or written factory liability for warehouse claims. Short delivery dates create pressure. Keep the decision tied to defect type, customer risk, and resale value.

Frequently Asked Questions

Is sock pre-shipment inspection needed for every order?

Use it for every new supplier, new yarn, new size spec, new packaging format, and retail shipment. For a repeat factory with 3 to 5 clean reports, some buyers inspect every second or third order. Do not skip inspection on orders with barcodes, fiber claims, licensed artwork, or tight delivery dates. One wrong UPC on 10,000 polybags can cost more than several inspections.

Can inspection happen after goods are packed in cartons?

Yes. That is the normal timing. At least 80 percent of the order should be packed, and the inspector must be allowed to open random cartons and reseal them. Leave 2 to 4 days before loading for sorting, relabeling, reboarding, replacement, or carton remarking.

What AQL level is common for sock inspection?

Many sock buyers use General Inspection Level II with AQL 2.5 for major defects and AQL 4.0 for minor defects. Critical defects should be zero. For a 10,000 pair order, the sample is often 200 pairs. At that sample size, 11 major defects fail under AQL 2.5, and 15 minor defects fail under AQL 4.0.

Should sock size be checked before or after washing?

Final inspection checks finished size after boarding because that is what the buyer receives. Wash shrinkage should be tested before bulk production or during pre-production approval. For cotton rich socks, shrinkage above 5 percent can cause fit complaints. If shrinkage matters, write the wash method, water temperature, drying method, and allowed tolerance in the tech pack.

What files should I send before booking inspection?

Send the purchase order, packing list, approved sample photos, size spec, artwork, barcode list, carton mark file, care label file, defect definitions, and AQL setting. If documents are required, send the relevant OEKO-TEX, GOTS, GRS, ISO 9001, BSCI, Sedex, or CE request where it applies. Also state the target inspection date, factory address, contact person, packed percentage, carton count, and release rule after the report.

Related Searches

sock pre-shipment inspection checklistAQL standard for sockssock factory inspection before shipmentsock quality control checklistthird party sock inspection Chinasock packaging inspection guide