Convertkit email verification with BillionVerify
ConvertKit is an email marketing platform built for creators and online businesses, offering tools for broadcasts, automated sequences, and subscriber management. Integrating BillionVerify ensures the subscribers entering your ConvertKit lists are real, active email addresses — keeping your deliverability strong and your list costs low.
Why verify before the send
Email marketing platforms charge by subscriber count, and poor deliverability from invalid or disposable addresses can trigger spam-filter flags that affect your entire account. Verifying emails with BillionVerify before they land in ConvertKit removes the addresses most likely to bounce or complain, protecting both your sender reputation and your budget.
Ready-to-use n8n workflow
Import this workflow into n8n — it verifies every address with BillionVerify before Convertkit sends, so only deliverable contacts are emailed. Install the BillionVerify community node first, then add your API key.
{
"name": "Verify emails before sending in ConvertKit + BillionVerify",
"nodes": [
{
"parameters": {},
"type": "n8n-nodes-base.manualTrigger",
"typeVersion": 1,
"position": [
240,
300
],
"name": "When clicking ‘Test workflow’"
},
{
"parameters": {
"assignments": {
"assignments": [
{
"id": "email-field",
"name": "email",
"value": "jane@example.com",
"type": "string"
}
]
},
"options": {}
},
"type": "n8n-nodes-base.set",
"typeVersion": 3.4,
"position": [
460,
300
],
"name": "Get contacts"
},
{
"parameters": {
"sendTo": "={{ $json.email }}",
"subject": "Message for ConvertKit contacts",
"message": "Replace this Gmail send with your ConvertKit node — only deliverable, verified contacts reach it.",
"options": {}
},
"type": "n8n-nodes-base.gmail",
"typeVersion": 2.1,
"position": [
900,
300
],
"name": "Send email",
"webhookId": "",
"credentials": {
"gmailOAuth2": {
"id": "",
"name": "Gmail account"
}
}
},
{
"parameters": {
"operation": "verify",
"email": "={{ $json.email }}",
"additionalOptions": {}
},
"type": "n8n-nodes-billionverify.billionVerify",
"typeVersion": 1,
"position": [
540,
300
],
"name": "Verify Email (BillionVerify)",
"credentials": {
"billionVerifyApi": {
"id": "",
"name": "BillionVerify account"
}
}
},
{
"parameters": {
"conditions": {
"options": {
"caseSensitive": true,
"leftValue": "",
"typeValidation": "loose"
},
"combinator": "and",
"conditions": [
{
"id": "is-deliverable",
"leftValue": "={{ $json.is_deliverable }}",
"rightValue": "",
"operator": {
"type": "boolean",
"operation": "true",
"singleValue": true
}
}
]
}
},
"type": "n8n-nodes-base.if",
"typeVersion": 2,
"position": [
720,
300
],
"name": "IF deliverable"
}
],
"connections": {
"When clicking ‘Test workflow’": {
"main": [
[
{
"node": "Get contacts",
"type": "main",
"index": 0
}
]
]
},
"Get contacts": {
"main": [
[
{
"node": "Verify Email (BillionVerify)",
"type": "main",
"index": 0
}
]
]
},
"Verify Email (BillionVerify)": {
"main": [
[
{
"node": "IF deliverable",
"type": "main",
"index": 0
}
]
]
},
"IF deliverable": {
"main": [
[
{
"node": "Send email",
"type": "main",
"index": 0
}
],
[]
]
}
},
"settings": {
"executionOrder": "v1"
}
}Workflow templates with Convertkit
Ready-to-use workflows that verify emails before Convertkit sends.
How it works
- 1
Set up an automation in n8n or Integrately that watches for new ConvertKit subscribers or form submissions.
- 2
Before the subscriber is tagged or added to a sequence, route their email to BillionVerify for verification.
- 3
BillionVerify checks the address against syntax rules, domain records, and live SMTP responses.
- 4
If the address is valid, allow the automation to complete normally and add them to ConvertKit.
- 5
If the address is invalid, disposable, or role-based, skip the ConvertKit add step or move the contact to a review tag.
When to use this
Verify new subscribers at the point of opt-in
When someone opts in through a landing page or form connected to ConvertKit, run their email through BillionVerify first. Only confirmed-valid addresses get added as subscribers, preventing bad data from entering your list.
Clean imported lists before adding to sequences
Before importing an external contact list into a ConvertKit sequence, bulk-verify the addresses with BillionVerify to remove undeliverable, disposable, and role-based emails and protect your account's deliverability standing.
Suppress invalid emails from lead magnet funnels
Lead magnets attract disposable-email entries. Add a BillionVerify check between your opt-in form and ConvertKit so only genuine subscribers receive your sequences — improving engagement metrics and list quality.
FAQ
Will using BillionVerify slow down my ConvertKit opt-in experience?
Real-time verification typically takes under a second. You can run it synchronously to gate form submission or asynchronously after the form confirms to the user, keeping the experience smooth.
Should I verify addresses already on my ConvertKit list?
Yes. Running your existing list through BillionVerify's bulk API and removing invalid contacts before your next broadcast reduces bounce rates and improves open-rate metrics immediately.
Does BillionVerify integrate with ConvertKit's tagging system?
Indirectly — through n8n or Integrately you can apply ConvertKit tags based on BillionVerify verdicts, for example tagging catch-all addresses separately for manual review.
What is the difference between a hard bounce and an address BillionVerify flags as invalid?
A hard bounce happens after you send and the server rejects delivery. BillionVerify catches invalid addresses before sending, so you avoid the bounce entirely and its negative impact on your sender score.
Verify emails in Convertkit
Create a free account, grab your API key, and stop bounces before they happen.
Get started free