How to Subscribe a Customer to ConvertKit When a WooCommerce Product Is Purchased

Sell a course or a digital product and want buyers automatically dropped into a ConvertKit sequence — onboarding emails, a drip course, an upsell sequence — without adding them by hand? Zapify does this with the free A product is purchased trigger and the Subscribe to a form action. ConvertKit is a Zapify PRO integration.

What this automation does

The automation is one trigger plus one action:

• Trigger: A product is purchased (WC_PRODUCT_PURCHASED, WooCommerce)
• Action: Subscribe to a form (CONVERTKIT_SUBSCRIBE, ConvertKit)

When an order containing the product you choose reaches a paid status, Zapify subscribes the buyer to the ConvertKit form you specify — which is what carries the sequence and any tagging on ConvertKit's side.

Before you start

• WooCommerce installed and active.
• A ConvertKit API key — from your ConvertKit account settings. See ConvertKit's developer docs if you can't find it. The API secret is not needed for this action.
• The Form ID of the ConvertKit form to subscribe people to — the number at the end of the form's URL in ConvertKit.

How to build the automation

Step 1: Connect ConvertKit

1. Go to Settings → Connections and click Add New.

2. Choose ConvertKit, paste in your API key, and name the connection something like Course ConvertKit.

3. Save. The API secret field can be left blank — it's only needed for actions that read or delete data, not for subscribing.

See Connections for how this screen works generally.

Step 2: Create a new automation

1. In the WordPress admin, go to Zapify → Automations.
2. Click Add New to open the builder.
3. Name it clearly, such as Subscribe buyers to course sequence.

Step 3: Add the "A product is purchased" trigger

1. Click Add Trigger.

2. Choose WooCommerce as the app.

3. Select A product is purchased.

4. Set the Product field to the specific product that should trigger the subscription.

Step 4: Add the "Subscribe to a form" action

1. Click Add Action.

2. Choose ConvertKit as the app, and select Subscribe to a form.

Step 5: Configure the action

Field	Required	What it does
Connection	Yes	The ConvertKit connection you set up in Step 1.
Form ID	Yes	The number at the end of the form's URL in ConvertKit.
Email address	Yes	Insert the Billing email token from the order.
First name	No	Insert the Billing first name token.
Tag IDs	No	Comma-separated. ConvertKit tags are numbers, not names — find a tag's ID in ConvertKit's own interface.

Step 6: Set the steps Live and save

1. Set both the trigger and the action to Live.
2. Click Save.

Step 7: Test it

Place a test order for the selected product using an email you control, and mark it as paid. Check ConvertKit's subscriber list for that form, or open Zapify → Logs to confirm the run.

Tokens you can use

The A product is purchased trigger exposes these tokens for the action's fields:

Token	Value
Billing email	Customer billing email
Billing first name / last name / phone	Customer details
Product IDs / Product names	The purchased products
Order ID / Order number	Order identifiers

Conclusion

With the free A product is purchased trigger and the Subscribe to a form action, Zapify enrols every buyer into your ConvertKit sequence the moment they pay. Combine it with an email when a product is purchased in the same automation, or grant course access at the same time with enrol a user on a LifterLMS course when a product is purchased.

FAQs

Is this free in Zapify?

The trigger is free. Subscribe to a form is part of the ConvertKit PRO integration and needs an active Zapify PRO licence and a Connection.

Why a form and not just "subscribe to my account"?

ConvertKit has no such call — a form is what carries the sequence and any tagging, so every subscription goes through one.

Do I need the API secret?

No, not for this action. The secret is only required for actions that read existing subscribers or remove them — subscribing only needs the API key.

Can I apply a tag at the same time as subscribing?

Yes, using the Tag IDs field. ConvertKit tags are identified by number rather than name, so look up the tag's ID in ConvertKit first.

Can I limit this to one specific product?

Yes, using the Product field in the trigger. Leave it as Any only if every product on the store should lead to the same subscription.

Do I need to write any code?

No. The connection and every field are configured visually — the API key is the only thing you copy from outside Zapify.