Ecommerce
Low-stock alerts and reordering: set a reorder point per product, get one daily digest, and approve the purchase order
Your bestseller is selling faster than usual because an ad finally worked. Nobody is watching the stock count. On Thursday it hits zero. The ad keeps spending, the product page says sold out, and your supplier needs three weeks to make more.
The fix isn't a person staring at a spreadsheet. It's a reorder point for each product that matters, an alert that fires early enough to act on, and a purchase order that is ready to approve when it does.
The short answer
Work out a reorder point for each product from its daily sales and your supplier's lead time. Get one daily digest of everything at or below that point. Have a draft purchase order ready for a person to check and send.
| Question | Short answer |
|---|---|
| What it is | Reorder points per product, an automatic low-stock alert, and draft purchase orders |
| What it is not | Purchase orders sent to suppliers with nobody checking them |
| Who it suits | Stores with products that take weeks to restock, especially former Stocky users |
| Cost range | Shopify's purchase orders, reports and Flow are free; planning apps from about $49 a month; a custom build has a setup fee and a monthly fee |
| What to do first | Write down the real lead time for each supplier, from order to stock on your shelf |
Why a single "low stock" number fails
Many stores set one rule for the whole catalog: tell me when anything drops below 10. That works for a product that sells one a week. For a product that sells eight a day, 10 units is about one day of stock. If the supplier needs three weeks, the alert arrives far too late.
One merchant described another problem in a Shopify Community thread on reorder alerts: "triggering individual emails per low-stock SKU creates inbox chaos." Thirty separate alert emails get ignored. One list a day gets read.
The reorder point, in one line
Shopify's own guide to safety stock and reorder points uses the standard formula. The reorder point is your average daily sales multiplied by the lead time in days, plus safety stock.
Safety stock covers the bad weeks. The same guide works it out as your highest daily sales multiplied by your longest lead time, minus your average daily sales multiplied by your average lead time.
Here is an example. A product sells 8 a day on average, and the supplier usually takes 21 days. That is 168 units sold while you wait. On its busiest days it sells 12, and the supplier's worst delivery took 25 days. That gives a safety stock of 300 minus 168, which is 132. So you reorder when stock falls to 300.
Two practical points. Use a sales window of 30 to 60 days, not one busy week. And measure lead time from the day you order to the day stock is on sale, not the supplier's quoted production time.
What Shopify gives you now that Stocky has gone
Stocky, Shopify's inventory app, stopped working on 31 August 2026. Its low-stock report worked out a reorder point for each variant from lead time and daily sales. Shopify now points merchants to tools in the main admin.
You can create purchase orders with suppliers, costs and payment terms, then receive stock through a linked transfer. You can't email a purchase order from the admin. You download a PDF and send it yourself. Shopify suggests storing minimum and maximum levels per variant in metafields. Sidekick, its built-in assistant, can suggest what to reorder and draft the purchase order.
For alerts, Shopify suggests Flow. Its templates include getting notified when product inventory is low, and hiding and republishing products by inventory level. Its advanced examples include a daily summary email of out-of-stock products. For the numbers, the days of inventory remaining report divides each variant's stock by its average daily sales over the last 28 days.
How to automate it, step by step
- Pick the products that matter. Your A-grade products, the ones that bring in most of your revenue, deserve their own reorder points. Shopify's ABC analysis report sorts them for you.
- Record the real lead time per supplier, and the worst one you have seen.
- Calculate a reorder point for each important product, and store it on the variant in a metafield.
- Run one scheduled check a day that compares available stock with each reorder point.
- Send one digest: what is at or below its reorder point, how many days of stock are left and how much to order.
- Draft the purchase order for each supplier, ready for a person to check and send.
- Recalculate the reorder points every month, or whenever sales or lead times change.
If you sell on more than one channel, the stock count has to be right before any of this works. Our post on why Shopify stores keep overselling covers getting one count that Shopify, Amazon and your 3PL all read. Returns that never get put back on sale throw the count off too, which our returns automation post covers.
Your options compared
Prices come from each provider's own page, checked in October 2026.
| Option | Typical cost | Good at | Trade-offs |
|---|---|---|---|
| Shopify admin and reports | Included in Shopify | Purchase orders, suppliers, transfers, days of inventory remaining | No built-in reorder alert; purchase orders go out as PDFs |
| Shopify Flow | Free app on Basic, Grow, Advanced and Plus | Low-stock alerts, daily digests, hiding sold-out products | Someone has to build it; Get data lists are capped at 100 items per run |
| Prediko | From $49 a month under $100K yearly sales, rising with sales | Forecasting, buying alerts and purchase orders in one app | Price grows with your revenue |
| Custom build | Setup fee plus monthly fee; our builds start at $200 | Reorder points from stock across Shopify, Amazon and your 3PL, with draft POs sent to your inbox | Only worth it when one app can't see all your stock |
What a stockout costs, on example numbers
Here is the sum for one bestseller. The numbers are my assumptions. Use your own.
| Line | How to get it | Example |
|---|---|---|
| Daily sales | Inventory sold daily by product report | 8 units |
| Days out of stock | From sell-out to restock | 12 days |
| Profit per unit | Price minus cost and shipping | $25 |
| Lost profit | 8 x 12 x $25 | $2,400 |
That leaves out the ad money spent sending people to a sold-out page, and the customers who buy from someone else and don't come back.
When it backfires
Bad lead times. If you use the supplier's best-case lead time, every reorder point is too low. Use what actually happened on your last few orders.
A busy week as the sales rate. A launch week or a sale makes a product look like it sells twice as fast. Reorder points built on it tie up cash in stock you don't need.
Purchase orders sent automatically. Suppliers have minimums, price breaks and holidays. Let the system draft the order, and have a person send it.
Alerts nobody owns. A digest that goes to a shared inbox and nobody reads is no better than nothing. Name the person who acts on it.
Forgetting stock that is already on order. If a purchase order is in transit, the alert should know, or it will ask you to order the same thing twice.
What we build, and when we say no
If you sell on Shopify alone with a modest catalog, set reorder points for your top products, switch on a Flow digest and use Shopify's purchase orders. You don't need us for that.
We build the next step for stores selling on several channels or with long supplier lead times. The system reads stock across Shopify, Amazon, TikTok Shop and your 3PL, recalculates reorder points from real sales and lead times, and sends one daily digest. It drafts the purchase order for each supplier. Our ecommerce automation work covers the whole order flow, and our workflow automation service connects the systems.
We say no when the stock count itself isn't trustworthy yet, or when an app already sees every channel. New to all this? Our plain-English answers to 24 questions about AI automation is the place to start.
Questions people ask
How do I get low-stock alerts in Shopify? Shopify doesn't send a reorder alert by default. Install the free Shopify Flow app and use its template for getting notified when product inventory is low, or build a scheduled workflow that emails one daily list of products at or below their reorder point.
How do I calculate a reorder point? Multiply average daily sales by the lead time in days, then add safety stock. Shopify's guide works out safety stock as highest daily sales times longest lead time, minus average daily sales times average lead time. Recalculate when sales or lead times change.
What replaced Stocky? Stocky stopped working on 31 August 2026. Shopify now handles purchase orders, suppliers, transfers and stock counts in the main admin, suggests Flow for low-stock alerts, and offers Sidekick to suggest reorders. Apps such as Prediko add forecasting.
Can Shopify create purchase orders automatically? Sidekick can draft purchase orders based on demand suggestions, but you review and send them. You can't email a purchase order from the Shopify admin; you download a PDF. Shopify says purchase order APIs aren't generally available yet.
Should purchase orders be sent automatically? Usually not. Suppliers have minimum order quantities, price breaks and holidays that a formula doesn't know. Let the system draft the order and flag it, and have a person check and send it.
How much safety stock should I keep? Enough to cover your worst realistic week. Shopify's formula uses your busiest daily sales and longest lead time against your averages. Keep more for products with unreliable suppliers, and less for slow sellers where cash matters more than speed.
Find out which products you are about to run out of.
Bring your top products and supplier lead times to the free audit. We work out reorder points with you, check how your stock count is kept, and tell you whether Shopify's own tools, an app or a build is the right step. If a Flow digest will do, we say so.
Book the free audit →Sources
- Shopify Help Center, migrating from Stocky to Shopify inventory management, checked October 2026
- Shopify Help Center, creating and managing purchase orders, checked October 2026
- Shopify Help Center, inventory reports, checked October 2026
- Shopify Help Center, examples of workflows in Shopify Flow, checked October 2026
- Shopify Help Center, schedules, get data and looping workflows, checked October 2026
- Shopify Help Center, Shopify Flow, checked October 2026
- Shopify, safety stock vs reorder point, checked October 2026
- Shopify Help Center, Stocky low stock report, checked October 2026
- Prediko, pricing, checked October 2026
- Shopify Community, when to reorder: why a fixed stock threshold fails, checked October 2026