Membership Validation at Checkout

Where to find this: Shopify admin → Settings → Checkout → Checkout rules. This isn’t a tab in the Yuko admin; it’s a Shopify Function (yuko-membership-validation) that ships with the Yuko app.

Introduction

Membership Validation is a cart and checkout validation function. When the cart contains a membership product, it checks whether the customer already has an active membership. If they do, checkout is blocked with the message “You already have an active membership”.

What problem this solves

Without it, an existing member could buy a membership product again and end up with two paid subscriptions. Members who want a different plan should switch plans from their customer account instead (see Profile Membership).

Where it appears

Shopify checkout. The error only shows when the rule blocks the purchase.

When to use

You sell more than one plan, or you want to make sure no customer pays for two memberships at once.

Overview

Runs on every cart and checkout validation.
Looks for products tagged YUKO:Membership:Product. Yuko adds this tag to each plan’s linked product.
Checks whether the customer has the YUKO:Membership tag. Yuko adds it to customers with an active membership and removes it when they no longer have one.
There’s nothing to configure in Yuko; the message is fixed.

Before you start

At least one membership plan exists in Membership → Plans, so its linked product carries the YUKO:Membership:Product tag.

Setup guide

1. Turn on the checkout rule in Shopify

Open Checkout settings

In your Shopify admin, go to Settings → Checkout.

Add the rule

In Checkout rules, click Add rule and choose yuko-membership-validation.

Turn it on

Turn the rule on and save.

2. Verify

Test as an existing member

Log in as a customer with an active membership, add a membership product to the cart and go to checkout. You should see “You already have an active membership” and be unable to complete the order.

Test as a non-member

Repeat as a customer without a membership. Checkout should proceed normally.

How it works

The rule reads the cart lines and the customer’s tags.
If no line is a product tagged YUKO:Membership:Product, checkout continues.
If there is one and the customer has the YUKO:Membership tag, the rule returns an error and checkout is blocked.

Limitations

It only checks for an existing active membership. It doesn’t restrict regular products to members.
It relies on Shopify customer and product tags. Don’t remove the YUKO:Membership or YUKO:Membership:Product tags manually.
Guest checkouts without an identified customer can’t be matched to a membership.

Best practices

Turn on the profile widget too. Members who want a different plan can upgrade or downgrade from their account instead of buying again.

FAQs

Can I use this to make products members-only?

No. The rule only stops existing members from buying a second membership.

Can I change the error message?

No. The message is set in the function.

Membership Plans

Create paid plans with benefits, pricing and members.

Members

Manage each customer’s membership, status and billing date.

Membership Widgets

Cart, checkout, profile and product-page widgets.