Mailersend email verification with BillionVerify
MailerSend is a transactional email platform built for developers and product teams that need reliable, programmatic email delivery. Integrating BillionVerify before sending through MailerSend ensures that only verified addresses receive transactional messages, protecting your sending domain and API throughput.
Why verify before the send
Transactional emails — receipts, password resets, notifications — are high-value and time-sensitive. Sending them to invalid or disposable addresses wastes API quota and drives up bounce rates that MailerSend monitors closely. BillionVerify validates addresses before they ever reach the MailerSend send endpoint.
Ready-to-use n8n workflow
Import this workflow into n8n — it verifies every address with BillionVerify before Mailersend sends, so only deliverable contacts are emailed. Install the BillionVerify community node first, then add your API key.
{
"name": "Verify emails before sending in MailerSend + 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 MailerSend contacts",
"message": "Replace this Gmail send with your MailerSend 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 Mailersend
Ready-to-use workflows that verify emails before Mailersend sends.
How it works
- 1
Before calling the MailerSend API in your application or n8n workflow, pass the recipient's email address to BillionVerify's REST API.
- 2
Receive a JSON response containing validity, disposable status, role-address flag, and catch-all indicator.
- 3
If the address is valid and not flagged, proceed with the MailerSend API call to send the transactional message.
- 4
If invalid or disposable, abort the send and log the result — optionally notify your team or update the user record.
- 5
Track aggregate verification outcomes alongside MailerSend delivery stats to measure the impact on bounce and complaint rates over time.
When to use this
Validate before triggering transactional sends
When a user action in your application triggers a MailerSend API call, first check the recipient address with BillionVerify. Invalid addresses are rejected at the application layer, preventing unnecessary send attempts and keeping your MailerSend bounce metrics clean.
Screen new user registrations
Route every new registration email through BillionVerify via the REST API before sending the welcome email through MailerSend. Disposable and invalid addresses are blocked before your sending reputation is touched.
Protect domain reputation in multi-tenant applications
SaaS products sending email on behalf of multiple customers need especially clean lists. BillionVerify's API can be called per-send to verify each unique recipient, ensuring that tenant-level bad data does not contaminate your shared MailerSend sending domain.
FAQ
Why verify before sending transactional emails through MailerSend?
Transactional email providers including MailerSend enforce bounce rate thresholds. Repeatedly sending to bad addresses risks account suspension. BillionVerify prevents this by catching invalid addresses before they are ever sent to.
Can I use BillionVerify alongside MailerSend in an n8n workflow?
Absolutely. Add the BillionVerify community node before the HTTP Request node that calls the MailerSend API. If BillionVerify returns an invalid result, an IF node skips the MailerSend call entirely.
Does BillionVerify support high-volume transactional verification?
Yes. BillionVerify offers both single-address real-time verification and bulk verification endpoints, so you can handle everything from single triggered sends to large batches of transactional recipients.
What about role addresses like noreply@ or admin@?
BillionVerify flags role-based addresses specifically. For transactional email you generally want to suppress these, as they are rarely monitored and often feed into complaint loops that harm your MailerSend reputation.
Verify emails in Mailersend
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