Reorder points on Shopify: the complete guide

The reorder point formula

The classic formula is short:

Example: a product sells 3 units a day on average and your supplier takes 10 days to deliver. You will sell roughly 30 units while waiting, so without safety stock the reorder point is 30 — order when the 31st-to-last unit sells. Every term matters: get lead time wrong by three days and the reorder point is off by nine units.

Safety stock and service levels

The naked formula assumes demand and lead time never vary. They always do — a product that averages 3 a day sometimes sells 8, and a 10-day supplier sometimes takes 15. Safety stock is the buffer that absorbs both kinds of variation, and the honest way to size it is statistical: measure how much your daily demand and lead times actually swing, then pick a service level — the percentage of demand you want to cover. Covering 95% of outcomes needs a bigger buffer than 90%; covering 100% is impossible without infinite stock, which is why it is a dial, not a switch.

A useful property of the statistical approach: products with no variance data yet — new products, freshly migrated catalogs — get a safety stock of zero rather than an invented number, and the buffer grows as real data accumulates.

Reorder point vs. order quantity

The reorder point answers when; it does not answer how much. Ordering just enough to climb back to the reorder point puts you right back at the trigger the moment stock arrives. A better pattern is ordering up to a target above the reorder point, and subtracting everything already on the way:

The last two terms are where manual spreadsheets quietly fail: forgetting an inbound transfer or an order you placed last week means ordering the same stock twice.

Where simple averages break: slow sellers

A 30-day average works for products that sell every day. For a product that sells once or twice a month, the average whipsaws: one sale entering or leaving the window can swing the estimate by double digits, and the reorder point jumps around with it. Estimating slow movers from how often demand occurs and how much per occurrence is far more stable than averaging a mostly-zero series — worth checking for in any app you evaluate if long-tail SKUs are a big share of your catalog.

Choosing a Shopify reorder point app after Stocky

Until 2026 the default answer was Stocky, free with POS Pro. Shopify retires it on August 31, 2026, and the native replacement — built-in purchase orders — records orders without suggesting them: no reorder points, no alerts, no lead-time storage (full comparison here). When evaluating a replacement, the questions that separate the field:

• Does it compute safety stock from your data, or ask you to guess a number?
• Does the suggested quantity subtract inbound stock and orders already placed?
• Can it store per-supplier lead times and minimum order quantities?
• Does the alert reach you where you work — email or chat — rather than only in-app?
• If you are coming from Stocky: can it import your existing reorder points and lead times?

UreyukiBox answers yes to all five — that is the niche it is built for — and we keep an honest list of what Stocky still did better in Stocky vs UreyukiBox.

Common questions