The underwear size mix is an inventory decision before it is a sizing decision: every pack carries a ratio of sizes, and the ratio the buyer confirms is the ratio the warehouse receives, sells through, or marks down. The wholesale buyer who plans the size assortment from the channel’s curve and adjusts it from the sell-through data builds a pack that moves, while the buyer who copies a generic size table builds an exchange line. Knitwear Base (Finetex), a China-based knit apparel manufacturer with over 20 years of experience, produces knit underwear and runs a wholesale program, which makes it a practical reference for how the size assortment should be planned.
Size Mix Inside Every Pack
The size mix is the pack’s hidden specification. The customer does not choose the pack by the size ratio, but the retailer sells it by the ratio, so the buyer should name the ratio per pack, per style, and per market before the order. The ratio that matches the channel’s curve is the ratio that minimizes the wrong-size returns and the markdowns.
| Assortment point | What it decides | The buyer’s input |
|---|---|---|
| Sizes per pack | Which customers the pack serves | The channel’s size curve |
| Ratio across sizes | How many of each size | The sell-through history |
| Style coverage | Which styles share the pack | The assortment plan |
| Market curve | How the ratio shifts by region | The destination’s data |
The ratio should also be read against the fit. A style that runs small shifts the effective ratio, because the customer who would buy a medium takes a large, so the buyer should verify the fit on the size set before finalizing the ratio. The fit-adjusted ratio is the ratio the channel actually needs.
Pack Formats: Single, Multipack, Assorted
The pack format decides how the size mix reaches the shelf. A single pack carries one size and serves the customer who knows exactly what to buy, a multipack carries one size in multiples and serves the value channel, and an assorted pack carries a mix of sizes and serves the retailer that wants a tested assortment. Each format changes the cost structure, the shelf story, and the size mix inside the pack.
The single pack keeps the size decision with the customer, which reduces the wrong-size exchange but slows the shelf turnover. The multipack concentrates the value on the core sizes, which works when the channel’s curve is narrow but fails when the sizes spread. The assorted pack spreads the risk across sizes, but the retailer inherits the odd-size leftovers if the ratio is wrong.
The buyer should confirm the pack formats the factory supports and what each format includes in the unit price, because the pack format belongs in the quote comparison. The pack that looks cheaper per piece may carry a weaker size mix or a thinner polybag, and the comparison only works on the same format.
The pack format should also be read against the label plan. A multipack needs the size and the fiber information readable at the pack level, while an assorted pack needs the per-piece labels to carry the details, and the buyer should approve the pack-level labeling with the sample. The label that matches the format is the label that keeps the shelf compliant.
Style Assortment for Wholesale
The style assortment decides which underwear styles share the order. Briefs, trunks, and boxers serve different fit preferences and different channels, so the buyer should plan the style mix from the channel’s history rather than from a balanced guess. The style that sells through in the channel earns the depth; the style that stalls earns the cut.
The style assortment should also follow the construction. A knit waistband and a knit body behave differently from a cut-and-sew construction, and the styles that share a construction can share the production planning, so the buyer should confirm which constructions the factory runs before spreading the styles. The assortment that matches the factory’s strengths is the assortment that runs on schedule.
The style mix should also be reviewed per reorder. The buyer should compare the sell-through by style and adjust the next pack’s style coverage, because the assortment is a living plan rather than a one-time selection. The review that moves the styles is the review that keeps the pack aligned with the channel.
Return Causes in Wholesale Underwear
The return causes in wholesale underwear cluster around the size and the fit. The wrong-size return comes from a size chart or a ratio that does not match the customer’s expectation, and the fit return comes from a style that runs differently from the chart. The buyer should track the return reasons separately, because the two causes need different corrections.
The size return is corrected in the chart and the ratio. The buyer compares the returned sizes with the sold sizes, finds the sizes where the return rate runs above the average, and adjusts the chart note or the pack ratio in the next order. The ratio that learns from the returns is the ratio that stops repeating the error.
The fit return is corrected in the style. When a style runs small, large, or short in a specific size, the buyer should adjust the grading or the fit note rather than the ratio, and verify the correction on the size set. The correction that reaches the pattern is the correction that reaches the customer.
Adjusting Ratios From Sell-Through
The ratio adjustment starts with the sell-through data, not with the return data alone. The buyer compares the sold units by size with the shipped units by size, finds the sizes that sell through faster and the sizes that lag, and shifts the next pack’s ratio toward the fast sizes while protecting the slow sizes’ floor. The data-driven ratio is the ratio the channel validates.
The adjustment should also be read against the season. The summer underwear mix can skew differently from the holiday mix, so the buyer should review the ratio per season rather than carrying one ratio across the year. The seasonal review catches the shift before the warehouse inherits it.
The adjusted ratio should be confirmed with the factory in writing, because the factory cuts to the order and the confirmed ratio is the ratio the pack receives. The buyer should also confirm the minimum structure per size, because a ratio that needs more of one size than the structure allows changes the order shape.
The ratio should also be checked against the market’s size conventions. The US, the EU, and the UK markets label underwear sizes differently, and a ratio built on one market’s labels does not transfer to another, so the buyer should confirm the size labels and the fit references for each destination before approving the pack. The market check belongs in the same sample approval as the label fields, because the size that carries the wrong reference is the size that comes back in the return line.
Wholesale Sizing Template
The template turns the assortment into a repeatable plan. For each style and pack format, the buyer writes the sizes, the ratio, the fit note, and the reorder trigger, and reviews the combination against the sell-through and the return data before each order. The template makes the size mix visible and the adjustment data-driven.
A distributor’s buying team would treat the sell-through-by-size review as the pack’s steering wheel: the ratio that follows the data reduces the exchange line and the markdown, while the ratio that follows the habit repeats the last season’s mistakes. The same team would verify the fit on the size set before the first bulk, because the fit-adjusted ratio is cheaper to build before the order than to correct after it.
Distributors can build the size plan against the underwear manufacturer page and confirm the pack formats and the quantity structure through Knitwear Base’s contact page. The underwear program details give the starting structure; the buyer’s sell-through data gives the ratio.
The template should be reviewed after each season, because the buyer who compares the planned ratio with the actual sell-through learns which sizes the channel kept. The next order then starts from the adjusted ratio, and the adjusted ratio is what keeps the wholesale underwear pack moving.
Frequently Asked Questions
Why is the size mix an inventory decision?
Because every pack carries a ratio of sizes, and the confirmed ratio is the ratio the warehouse receives, sells through, or marks down.
What are the pack formats for underwear?
Single packs for the customer who knows the size, multipacks for the value channel, and assorted packs for the retailer that wants a tested mix.
How do I choose the style assortment?
From the channel’s history, with the styles that sell through earning the depth and the styles that stall earning the cut, reviewed per reorder.
What causes wholesale underwear returns?
Wrong-size returns from a chart or ratio that misses the customer’s expectation, and fit returns from a style that runs differently from the chart.
How do I adjust the size ratio?
Compare the sold units by size with the shipped units, shift the ratio toward the fast sizes while protecting the slow sizes’ floor, and confirm the change in writing.
What belongs in the wholesale sizing template?
The sizes, the ratio, the fit note, and the reorder trigger per style and pack format, reviewed against the sell-through and return data before each order.
What MOQ applies to a wholesale underwear order?
According to the underwear page, the full-customization MOQ is 1,000-3,000 pieces per design with mixed sizes; confirm how the minimum applies per style, color, and size.
