Shopify Inventory Alerts Setup: Thresholds, Owners, Notifications to Prevent Stockouts

A Shopify inventory alerts setup tells a named person when a specific variant needs a purchase order, a transfer, or a pause on ads, while there is still time to act.

The reorder point and the safety stock buffer are calculated in other guides. This page is the message, the owner, and the test that proves the message arrived. The wider weekly inventory routine, including which SKUs get cash first, lives in the Shopify inventory management system post.

What you need before the first alert

Turn on one alert only after these five facts are true. A missing fact produces email, not a reorder.

• Inventory tracked is on for that variant. Shopify treats an item as out of stock when inventory is tracked and the level is zero or below.
• You know which location fulfills online orders. Stock sitting at a location that does not fulfill online orders does not keep the product buyable.
• You already have a reorder point in units for that variant.
• You know the supplier lead time in days, even if the buffer math lives in another post.
• One person can place the order or write down why they will not.

Decide which SKU alert requires action

Start with variants you will actually reorder this month. Use ABC analysis to keep the first batch small. A dead variant with two units left does not need a reorder ping.

• The variant is selling, or a launch is about to make it sell.
• Someone can still place a supplier order, move stock, or stop ads before Available hits zero.
• The next action is already named: purchase order, transfer, preorder, or stop promoting.
• You trust the count. If Available and the shelf disagree, fix that before the alert, using the inventory discrepancy checks.

Include variants set to Continue selling when out of stock. Shopify lets customers buy those items after the level reaches zero or below, so the storefront will not stop the sale for you. Skip products with inventory tracking off. Shopify Flow's Product variant inventory quantity changed trigger still starts a workflow when tracking is off, so an unfiltered workflow will email you about products you never count.

Set the threshold from the reorder point

Put the unit reorder point into the alert. Get that number from the Shopify reorder point formula. The buffer inside it is the safety stock calculation. Do not rebuild either formula on this page, and do not add a second buffer unless the notification itself is delayed.

An immediate email can use that reorder point as the line. A weekly digest cannot. If people only read the list on Monday, the message has to leave before the reorder point, or the order is late by the days the digest sat unread. Move a digest threshold up by about one week of that variant's sales, and label the gap as digest delay, not as extra safety stock.

Example, using made-up numbers: the reorder point for a serum variant is already 180 units. The immediate alert fires when Available at the online warehouse drops to 180 or below, and the quantity before that change was above 180. A Monday-only digest for the same variant should sit about seven days of sales above 180, so the email is not the first sign that you are already inside lead time.

Shopify's old Stocky low-stock report used a thinner warning. Its help page gives the example of 5 blue socks a day and a 10-day lead time, which triggered at 50 units, with no separate buffer. Stocky is no longer available as of August 31, 2026. Do not rebuild alerts there. Shopify's migration guide points low-stock alerts to Shopify Flow.

Watch Available at the fulfilling location, not On hand. Shopify defines On hand as Committed plus Unavailable plus Available. Unavailable can include units an app has set aside, and Incoming is not sellable until it is received. If Available and the count on the shelf do not match, reconcile that inventory discrepancy before you trust the ping.

Assign a recipient and an escalation path

An alert without an owner is a log. Pick one person who must answer the same business day, then pick the backup who checks that answer the next morning.

Build the immediate email in Shopify Flow

Shopify documents staff low-stock email as a Flow workflow, including a template named Get notified by email when product variant inventory is low. Install Shopify Flow from the App Store, then open it in the admin. There is also a scheduled template, Send weekly email summary with list of low stock variants, for the digest row above. Both names are listed in Shopify's Flow template library.

Use the crossing check only when the quantity you compare is the same quantity the trigger reports before and after the change. inventoryQuantityPrior is the previous inventory quantity for the product variant, not the previous Available quantity at one location. On a store with stock at more than one location, that prior value can differ from location-level Available, and a condition that mixes the two can miss the crossing or email again after it. Limit this recipe to a variant whose inventory is only at the fulfilling location, or to a store with a single location, so variant quantity and that location's Available move together.

1. Create the workflow from the low-stock email template, or start manually with the trigger Product variant inventory quantity changed.
2. Add a condition for the fulfilling location. Shopify documents location quantity at productVariant / inventoryItem / inventoryLevels / available, and the location name or ID on that same inventory level.
3. Only if variant quantity and that location's Available are equivalent: fire when Available is at or below the reorder point and inventoryQuantityPrior was above that line. That is the crossing check. If stock also sits at other locations, do not use this pair. Use the low-stock email template's condition, or alert when location Available is at or below the line and accept that later changes can email again until you add a verified location-level prior.
4. Add Send internal email. Type the owner's address. Separate extra addresses with a comma. Flow cannot use a variable in the To field.
5. Put the SKU, location, threshold, and owner name in the subject. A person should know the action before they open a dashboard.
6. Leave the workflow off until the test below passes. Then turn it on for the first small set of variants, not the whole catalog.

The message should carry the decision, not a vague warning.

• Product title, variant, and SKU
• Fulfilling location and Available quantity
• Quantity before the change, only when you used the single-location crossing check
• The named action: create a purchase order, create a transfer, or pause ads
• The owner and the time the decision is due

Do not start with Flow's Initiate reorder with vendor template. That template emails the supplier when inventory is low. Confirm the quantity first, then create the purchase order in the Shopify admin. Also do not attach Unpublish product to this reorder alert. A low-stock email should not hide a variant that still has units to sell. Shopify's Product variant out of stock trigger is the one its templates use when a variant drops to zero or below.

Write the escalation before you need it

Agree the path in one paragraph and paste it under the email template.

• The owner acts the same business day: purchase order, transfer, or a written do-not-reorder note with a reason.
• If that note is missing the next morning, the ops lead chases that SKU only.
• If remaining cover is already shorter than lead time, the person who controls ads for that product gets a same-day pause note.
• Every alert gets a row: SKU, time sent, owner, decision, and purchase-order or transfer number.

Rank a late alert by what a day at zero is worth, using the stockout cost formula rather than a storewide loss figure. The pause-ads decision belongs with the product-led marketing routine, not with a second inventory email to the same buyer.

After one native alert works, use velocity and cover to decide which emails deserve that same-day owner. Skymetrics Stock Intelligence describes a notification by email or in the dashboard when a product reaches a reorder point, and it uses 14 days of stock remaining as an example, not as a default to copy. The Shopify App Store listing says the app predicts stockouts and includes notifications. Confirm the channel inside the app before you put it on the escalation path. A ranked reorder-versus-promote list is a separate job on the AI agents page.

Test one alert end to end

Shopify's trigger docs say to test by changing a product's inventory. Do that on one variant before you trust the workflow. A draft order is a bad test: Flow's notes say draft orders do not affect available inventory until they are converted to orders.

1. Pick one tracked variant whose reorder point you can disturb. A slow size is safer than the hero SKU. Use a variant stocked only at the fulfilling location if you are testing the crossing check.
2. Write the expected result first: recipient, subject, location, and threshold.
3. In the admin, change inventory so Available at the fulfilling location crosses that threshold.
4. Open the workflow run. Confirm it ran, then confirm the email is in the owner's inbox, including spam.
5. Change the quantity by one more unit in the same direction. A crossing condition should not send a second email. Skip this step if you did not use inventoryQuantityPrior because stock exists at other locations.
6. Restore the original quantity.
7. Turn the workflow on only after the steps you expected match what you wrote down.

If the email does not arrive, check the sender address. Shopify's Send internal email docs say some inboxes display the sender with via shopifyemail.com, or as store plus your shop ID at shopifyemail.com, when the sender domain is not authenticated. Filtering that address will make a correct workflow look broken.

Common mistakes

• Alerting on On hand, so committed or unavailable units hide a sellable shortage.
• One threshold for every SKU, including variants you will never reorder.
• A shared inbox and no name in the subject.
• A zero-only trigger for products with a multi-week supplier lead time.
• A location total that hides zero at the location that fulfills online orders.
• Continue selling when out of stock left on, with no reorder alert, because the product page never shows sold out.
• Comparing location Available with variant-level inventoryQuantityPrior on a multi-location variant.
• Turning on a vendor email or an unpublish action before a human has tested the staff email.
• Rebuilding the old Stocky daily report. That email was optional, passive, sent at 00:00 UTC, and limited to one address, and the app is no longer available.

Review alert noise and missed reorders weekly

Spend about 20 minutes a week on three lists. Do this before you add more variants.

• Alerts with no decision. That is an owner or escalation failure, not a threshold failure.
• Variants that hit zero Available with no alert during the prior lead time. The line is late, or the location condition is wrong.
• Alerts you ignored because you will not buy that SKU. Remove those variants, or limit the workflow to the A group.

This review is only the alert loop. Cash limits, the rest of the weekly metrics, and the reorder meeting stay in the inventory management system guide.

How to know the setup worked

You can point to one workflow run, one email in the owner's inbox, and one logged decision for the test variant. In the following week, every alert on the short list has a decision, and any new zero on an alerted variant has a note explaining why the alert was late or ignored.

That is the operating check. It does not promise that stockouts stop. Turn on one crossing-threshold email for one variant today, test it, and leave the rest of the catalog off until that test passes.