Plunk

Campaigns, workflows, and application email with cloud or self-hosted deployment.

What is Plunk?

Plunk combines newsletter campaigns, event-triggered workflows, and transactional email. The hosted service includes contact storage, API access, and SMTP delivery. Its cloud pricing charges for email usage rather than the number of stored contacts.

Plunk also offers an open-source edition that you run on your own infrastructure with Amazon SES. The self-hosted edition includes campaigns, workflows, and transactional delivery without the cloud service’s per-email usage charge. Hosting, database services, maintenance, and SES delivery remain your responsibility.

Official details: https://www.useplunk.com/pricing ; https://www.useplunk.com/open-source-email-platform

Pricing: Cloud has a free monthly allowance and usage-based paid delivery at $0.001 per ordinary email. Self-hosted software has no license fee; infrastructure and SES delivery are separate. Pricing checked October 26, 2026.

Features

Newsletter campaigns
Event-triggered workflows
API and SMTP delivery
Unlimited stored cloud contacts
Open-source self-hosting

FAQs

Common questions about Plunk

Do cloud and self-hosted Plunk have the same bill?

No. Cloud charges for usage on its hosted service. Self-hosted Plunk has no cloud usage charge, but you operate the infrastructure and pay your delivery provider.

Does every cloud email use one credit?

Ordinary outbound messages use one credit. Inbound messages share the allowance, and messages with attachments use two credits.