Three Shopify Flow rules every multi-supplier store should have
Shopify Flow is the best-kept secret in the Shopify ecosystem. It is free on most plans, it reads metafields, and it can do about 80 percent of the inventory ops work that multi-supplier merchants do by hand. Three rules that pay back their setup time within a week.
Rule 1: Hide on zero
Trigger: when both stock.on_hand and stock.with_supplier change to zero.
Action: set the product's published status to false, or remove it from the Online Store channel.
Why: you are not wasting paid ad budget on a product that cannot ship, and you are not disappointing shoppers with a "Sold out" page when your supplier has nothing either. When a supplier reports stock again, Flow can re-publish.
Rule 2: Tag low stock
Trigger: when stock.on_hand drops below your threshold — 5, 10, whatever fits your velocity.
Action: add the tag low-stock to the product. On refill, a second rule removes it.
Why: your collection filters can include or exclude low-stock products. Your buying team can filter all products tagged low-stock into a reorder view. Your storefront copy can adjust urgency.
Rule 3: Email the buying team when a key product hits zero
Trigger: when stock.on_hand for a product tagged hero or top-seller changes to zero.
Action: send an email to your buying team with the product name and last known stock level.
Why: your top products should never go out silently. Manual Slack threads miss things; Flow emails do not.
Beyond these three: the useful weird ones
Tag products by delivery window (ships-now, 3-5-days, 10-plus-days) based on your metafields and a lead-time field. Drive your collection filters off those.
Apply a discount metafield when stock is high and a supplier is pushing a particular line. Or send a reorder reminder Slack message when on-hand drops below reorder point while supplier stock is above restock quantity.
The rule of thumb
If a human is checking a stock number and doing the same action based on it three times a week, that is a Flow rule. Your buying team's time is better spent on exceptions and supplier relationships.
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