Open Source Email Marketing
Email marketing runs on two things you never fully own with a hosted sender: the subscriber list, which is metered so the bill climbs with every contact you add, and the sender reputation that decides whether your campaigns reach the inbox at all. A flagged account can be suspended with your entire audience still locked inside it. The open source options here keep the list, the consent records, and the sending logic on infrastructure you run, and most of them separate campaign management from delivery so you can change providers or route mail through your own relay without rebuilding everything. The relationship with your readers stays portable instead of held hostage to one vendor's pricing.
listmonk
Self-hosted newsletter, mailing list, and transactional email manager with a single-binary app and PostgreSQL
BillionMail
Self-hosted open-source mail server and email marketing platform with analytics and customer management
Mautic
Open source marketing automation with self-hosting, lead management, and privacy-focused campaign control
Mailtrain
Self-hosted newsletter app with subscriber lists, segmentation, MJML templates, automation, and reports
Dittofeed
Open-source customer engagement for broadcasts and automated journeys across email, SMS, push, WhatsApp, and Slack
SendPortal
Self-hosted email marketing and newsletter software with subscriber lists, campaigns, tracking, and reports
Keila
Open source email newsletter tool for campaigns, sign-up forms, and self-hosted sending
phpList
Open source email marketing manager for newsletters, campaigns, analytics, and subscriber segmentation
Our picks
Best for high-volume newsletters: listmonk listmonk is a single Go binary backed by PostgreSQL, so a self-hosted newsletter and mailing-list setup stays lean to operate. It sends campaigns and transactional email, connects to your SMTP or provider of choice, and installs from a binary or Docker. A good default when you want a fast, no-frills sender you fully control.
Best for marketing automation: Mautic Mautic goes beyond blasts into lead management, unlimited segmentation, and multi-channel campaigns, with a fully customizable front and back end for building your own integrations. It suits teams replacing a hosted automation suite who want the journey logic and contact data on their own infrastructure.
Best for event-driven journeys: Dittofeed Dittofeed is built for automated journeys across email, SMS, push, WhatsApp, and Slack, fed by Segment, Reverse ETL, or its own API. Developer touches like Git-based campaign version control and a CI testing SDK make it a strong fit for lifecycle messaging that lives close to your product.
Best for smaller senders: Keila Keila handles newsletter campaigns and sign-up forms, and can send smaller lists straight through your own email inbox before you graduate to SES, Sendgrid, Mailgun, or Postmark. Self-host it with the official Docker image, or use Keila Cloud for a low-friction start.
Matching an email tool to how you actually send
The first fork in the road is whether the tool sends mail itself or hands delivery to a provider. Some of these run their own delivery path - Mailtrain bundles a Zone-MTA, and BillionMail is a full mail server - which means you also inherit IP reputation, bounce processing, and authentication like SPF, DKIM, and DMARC. Others, including listmonk, Keila, and SendPortal, deliberately manage contacts and campaigns while leaning on Amazon SES, Sendgrid, Mailgun, or a plain SMTP relay for the actual send. That split is usually the safer one, because a dedicated sender handles reputation and complaint feedback better than a fresh server ever will.
Next, look at how each tool models contacts and consent, because that shapes everything downstream. A newsletter-first app that thinks in lists is simple until one person belongs to several audiences; a tag, segment, or event model handles overlap and exclusions more gracefully. phpList and Mautic lean toward richer segmentation and automation, while a single-purpose sender keeps the mental model small. Whatever you pick, confirm it records subscription status, source, and unsubscribe state cleanly, so you never accidentally mail someone who opted out.
Finally, match the workflow to what your team really does. A newsletter team needs a solid editor, reusable templates, scheduling, and test sends; a lifecycle team needs triggers, webhooks, and API access, which is where an event-driven tool like Dittofeed fits. Before committing, send a real campaign end to end and export the results, since contacts, segments, and suppression lists should all come back out in a format another system can read.
Related categories
Frequently asked questions
Do I still need a separate email delivery provider?+
Usually, yes, and often that is the right design. Several tools here - listmonk, Keila, SendPortal - manage contacts and campaigns but send through Amazon SES, Sendgrid, Mailgun, Postmark, or SMTP, because a dedicated sender handles rate limits, bounce feeds, and complaint loops better than a basic server. The exceptions are BillionMail, which is itself a mail server, and Mailtrain, which ships a built-in Zone-MTA if you want to run delivery yourself.
Does self-hosting the app give you good inbox placement?+
No. Running the software on your own server does nothing for sender reputation, which depends on domain history, IP warmup, authentication, complaint rate, and list hygiene. New sending infrastructure usually needs slow warmup and strict throttling before mailbox providers trust it. This is exactly why many teams self-host the marketing app but route the actual mail through an established delivery provider with an existing reputation.
How do these tools deal with bounces and complaints?+
Bounce and complaint handling separates a real email platform from a form that sends mail. phpList includes bounce processing and message-queue management, and tools that integrate with SES or Postmark can consume their bounce and complaint feedback. What matters is that hard bounces and spam complaints automatically suppress an address, so your list stays clean and your reputation does not erode with every send.
Can one tool handle both marketing and transactional email?+
Some can, but mix them deliberately. listmonk and Dittofeed both support transactional messages alongside campaigns, which simplifies branding and infrastructure. The risk is that a poor-quality marketing list can drag down the sending reputation your password resets and receipts depend on. If both matter, many teams keep transactional mail on a separate stream or domain so a marketing complaint spike never blocks critical account email.
What consent and unsubscribe records should the tool store?+
Look for subscription status, consent source and timestamp, unsubscribe timestamp, and suppression records, not just a flat list of addresses. Under GDPR or CCPA you need to prove when and how someone opted in, and answer deletion requests without corrupting campaign history. A tool that only exports email addresses loses the context that makes a migration or a compliance audit defensible later.
Is open and click tracking still reliable?+
Open tracking has become noisy because mailbox privacy features and image proxying inflate or fake opens. Click tracking is steadier but rewrites your links, which is worth disclosing. Many teams now lean on UTM parameters and downstream analytics instead of per-recipient pixels. Decide what you actually act on, then keep only the tracking that supports those decisions rather than collecting everything by default.
Which tools suit automated journeys versus simple newsletters?+
For scheduled newsletters, a focused sender like listmonk, Keila, or SendPortal covers editing, templates, and delivery without extra moving parts. For event-driven journeys across email, SMS, and push, Dittofeed is built around triggers, segments, and API-fed user data, and Mautic adds broader multi-channel automation and lead management. Prototype your hardest automation first, because a welcome email proves very little about a tool's real workflow ceiling.