One free sample per customer. One limited edition item per household. One promotional price per account. These are simple rules in principle — but Shopify has no native way to enforce them. Here is how to do it.
Why One-Per-Customer Rules Are Hard on Shopify
Shopify’s checkout validates stock levels and discount codes, but it does not track per-customer purchase history for quantity purposes. A customer can place an order for 1 unit, then come back and place another, and Shopify will fulfil both without question.
Enforcing a true one-per-customer limit requires an app that checks purchase history at checkout time.
Setting Up a One-Per-Customer Rule on Shopify
Install Fold
Fold supports per-customer lifetime limits via Shopify Functions. Install it from the Shopify App Store.
Create a Per-Customer Limit rule
In Fold, create a new rule and select Per-Customer Limit. Set the lifetime maximum to 1. Target the specific product, variant, or collection. Write your message: “This item is limited to one per customer.”
Require customer login
Per-customer limits work best with required login. In Shopify Settings → Checkout, set accounts to required for checkouts involving the limited product. Guest checkouts cannot be reliably tracked across sessions.
Use Cases
Free sample
Offer a free or heavily discounted sample product. Set a per-customer limit of 1. The customer can only claim it once across their entire purchase history with your store.
Limited edition collectible
A limited run of 500 units. Each registered customer can buy one. Once purchased, they are locked out from buying a second — even in a separate order months later.
Introductory offer
New customers get a first-order price. Set the promotional variant to a per-customer limit of 1 so returning customers cannot repeatedly access the introductory rate.
Frequently Asked Questions
What if someone creates a new account to bypass the limit?
Per-email tracking catches most cases. For very high-value limited items, pair the limit with a manual review step or identity verification for first-time purchasers.
Can I limit to one per order but allow multiple orders?
Yes — use a maximum quantity rule (per cart) instead of a per-customer lifetime limit. One caps a single cart; the other caps all-time purchases.
Install Fold to limit purchases to one per customer on Shopify — free samples, limited editions, introductory offers.
