Quote with the window — 70% at 30 days reads differently from 70% at 90 days.
Sell-through rate is the share of received inventory sold during a defined period — over a defined window. A 70% 30-day sell-through on a drop means 70% of the units that landed in the warehouse cleared within 30 days of receipt. Some operators use beginning-period inventory available as the denominator instead; the receipt-window form is the cleanest read for buy planning, but pick one and label which.
The window is part of the metric. Quoting sell-through without naming the window is meaningless: a 70% number at 30 days reads differently from the same number at 90 days, because the second hides three months of carrying cost and a much higher risk that what is left will need to move on markdown.
Sell-through is also a per-SKU read, not a portfolio one. A brand-level number averages hero SKUs against dead inventory and tells the operator almost nothing actionable. The diagnostic only works at the SKU or style level, week-over-week against the buy plan.
Benchmarks vary by category
Fashion drops typically aim for 60–80% at full price within 8–12 weeks; replenishment categories like basics and consumables target much higher steady-state sell-through with continuous reorder. These ranges are operator conventions, not laws — channel mix, season, price point, and promotional cadence all shift the target, and a brand running flash sales reads differently from one anchored on full-price retail. The benchmark that matters most is the brand’s own historical curve for the category.
What the number triggers
Sustained high sell-through on a SKU triggers reorder analysis: the brand under-bought, demand is real, and the question is whether the lead time supports a refill before the window closes. Sustained low sell-through triggers markdown or clearance planning, with markdown depth set by how far the SKU is from the target sell-through curve for its category.
The reorder-vs-markdown call combines sell-through with contribution margin. A low-sell-through SKU with high contribution margin may be worth holding through the season; a low-sell-through, low-margin SKU is a markdown candidate, because the carrying cost and shelf space outweigh the thin profit on each unit sold. Brands that look at sell-through alone tend to over-discount their best gross-margin SKUs and under-discount the ones that are actually trapping cash.
Sell-through and inventory turnover answer related but different questions. Sell-through is per-SKU and per-receipt-window; turnover is portfolio-level and per-period. They can disagree — high turnover with a long tail of low-sell-through SKUs usually means a few hero SKUs are pulling the blended figure up while slow movers tie up working capital underneath.