Newsletter ESP integrations
MailAdx works with any email service provider that supports custom HTML in templates. Pick your ESP below for a step-by-step setup guide — merge field syntax, editor tips, billing notes, and troubleshooting.
Start freeHow ESP integrations work
Unlike web ad tags that run JavaScript in the browser, newsletter ads must work inside Gmail, Apple Mail, and Outlook — environments that block scripts and prefetch images. MailAdx solves this with open-time ad serving: you paste a dynamic image URL into your ESP template once. When a subscriber opens the email, their client requests that URL and MailAdx runs a real-time auction, returning the winning creative.
Every integration follows the same pattern: create a publisher ad unit in MailAdx, copy the HTML ad tag, substitute your ESP's email-hash merge field, and paste into a custom HTML block. No webhooks, no per-subscriber API calls, and no changes to your sending infrastructure. Impressions count only on genuine opens — not the full send list.
Publishers on Beehiiv, Mailchimp, and Klaviyo typically go live in one afternoon. ESPs that require a custom profile property for SHA-256 hashing (HubSpot, ActiveCampaign, SendGrid API sends) need an extra data-prep step — each guide below documents the exact approach for that platform.
Major ESPs
Beehiiv
Major ESP
Monetize your Beehiiv newsletter with open-time ads
Mailchimp
Major ESP
Add programmatic and direct ad revenue to your Mailchimp newsletter
Klaviyo
Major ESP
Monetize your Klaviyo email lists with newsletter ads
ConvertKit (Kit)
Major ESP
Add newsletter ad revenue to your ConvertKit broadcasts
SendGrid
Major ESP
Integrate MailAdx with SendGrid for newsletter ad monetization
ActiveCampaign
Major ESP
Add newsletter ad revenue to your ActiveCampaign campaigns
Campaign Monitor
Major ESP
Integrate MailAdx with Campaign Monitor newsletters
HubSpot
Major ESP
Add newsletter ad revenue to HubSpot marketing emails
Growing & specialty platforms
Ghost
Monetize your Ghost newsletter with MailAdx ads
Brevo (Sendinblue)
Monetize your Brevo email campaigns with MailAdx ads
Substack
Earning beyond Substack's platform with MailAdx
Mailmodo
Add MailAdx open-time ads to your Mailmodo newsletters
MailerLite
Monetize your MailerLite newsletter with open-time ads
Constant Contact
Integrate MailAdx with Constant Contact newsletters
Ready to monetize your newsletter?
Free to start. No revenue share. Pick your ESP guide and go live this afternoon.