Inventory management for Shopify denim brands

The inventory problems denim brands run into

• Size and inseam grids. a single style can split into 20-40 variants once you cross waist size with inseam and wash, and each one sells at a different rate.
• Fit skew. most brands sell a bell curve of sizes, with the middle sizes moving fast and the small and large ends moving slow, which throws off simple average-based reorder math.
• Wash and fabric dye lots. denim often runs in dye batches, so a reorder from the same supplier months later may not match the original wash exactly.
• Core vs seasonal styles. a brand usually has core 5-pocket styles that sell year-round alongside seasonal washes or colors that only matter for one season.
• Long production lead times. woven denim fabric, cut-and-sew, and finishing (stonewash, enzyme wash) add up, so reorders placed late can miss the selling window entirely.

Seasonality and demand

Denim has a back-to-school bump and a strong fall and holiday peak as heavier weights and darker washes come back into rotation, then a slower stretch in high summer when lighter fabrics and shorts take share. Many brands also run seasonal colors or washes that are only relevant for one drop. Plan ahead of fall by placing core-style reorders in summer, since lead times for cut-and-sew production mean late summer is often too late. For seasonal washes, treat them like a one-season bet: order close to what you can sell and do not expect a mid-season top-up from the same dye lot.

Suppliers, lead times and minimums

Denim brands typically work with cut-and-sew manufacturers (domestic or overseas) who produce against a purchase order, often with a minimum per style and color, and case packs built around a pre-set size ratio (for example a grid of 2-3-4-3-2 across sizes). Overseas manufacturers often take several weeks for production plus shipping, while domestic cut-and-sew shops are usually faster but pricier. Fabric mills themselves may require separate lead time if your manufacturer does not hold fabric stock, which stacks on top of garment production time.

Worked example

Say your straight-leg jean in size 32x32, indigo wash, sells 2 units a day on average. Your cut-and-sew supplier has a 42-day lead time and you keep 10 safety days for shipping delays. Reorder point = 2 x (42 + 10) = 104 units, so you trigger a new order once stock on hand plus incoming falls to 104. For order quantity, if you want 60 days of cover, order quantity = 2 x (42 + 60) - (on hand 90 + on order 0) = 204 - 90 = 114 units, which you would then round up to match the supplier's size-ratio case pack.

Try it with your own numbers in the reorder point calculator, or size your buffer with the safety stock calculator.

A simple system to start this week

1. List every style-wash-size-inseam combination as its own SKU so forecasts are per variant, not per style.
2. Get each supplier's real lead time, including fabric sourcing time if they do not stock it, and enter it per SKU.
3. Set safety days higher for overseas cut-and-sew suppliers and lower for fast domestic ones.
4. Separate core 5-pocket styles from seasonal washes so reorder timing matches each one's actual selling window.
5. Confirm each supplier's case pack size ratio and minimum order quantity before you set reorder quantities.
6. Review the weekly reorder email against upcoming season changes so you order ahead of back-to-school and fall demand.

How SteadyShelf fits denim brands

SteadyShelf forecasts each size and wash variant, tells you the order-by date based on your supplier's lead time, and rounds suggested quantities to the supplier's case pack and minimum. It drafts the purchase order and emails it on your approval, then lets you receive stock as it arrives, including partial shipments split across washes. It does not track dye lot or batch numbers, so if wash-matching across production runs matters to your brand, keep that detail in your supplier records or product notes outside the app.

$29/month flat, unlimited products and suppliers, 30-day free trial.

SteadyShelf is launching on the Shopify App Store. Join early access to get the install link first.

More: inventory management by store type · inventory glossary · Stocky alternatives

FAQ