Best Mailchimp alternatives for developers in 2026

For developers moving an app's email off Mailchimp, Unitpost ranks first: contacts sync from your code, receipts and newsletters share one list, and the bill follows sends, not contacts. Loops has the most polished editor for SaaS teams, Brevo prices by volume with SMTP included, Customer.io suits event-driven messaging, and Kit or Buttondown fit a newsletter alone.

Updated November 2, 2026. We make Unitpost, and it is on this list. Every score has a reason and the weights are published below, so you can re-rank it for your own needs. How we scored

#	Product	Best for	Free plan	Score
1	Unitpost	apps that send product and marketing email	5,000 emails a month, 200 a day, no card	4.9
2	Customer.io	messaging driven by product events	None; 12 months free for eligible startups	3.8
3	Loops	SaaS teams that want a polished editor	1,000 contacts and 4,000 sends a month	3.7
4	Brevo	teams that want a full marketing suite	300 emails a day	3.6
5	Kit	creators moving a newsletter	Up to 10,000 subscribers	2.6
6	Buttondown	a developer's own newsletter	Up to 100 subscribers	2.6

Why developers look for a Mailchimp alternative

Unsubscribed and non-subscribed contacts count toward the contact limit and the price tier.
Transactional email is an add-on for Standard and Premium only, sold in blocks of 25,000 emails; Essentials can't add it.
The free plan is 250 contacts and 500 sends a month, at most 250 a day.

When Mailchimp is still the better choice

Marketers build most of your email in a drag-and-drop editor and rarely touch code
You rely on Mailchimp's templates, landing pages and integrations
You want official SDKs in nine languages for the marketing API

Moving your list off Mailchimp

Export from Audience, then Export audience, then Export CSV: the export includes subscribed, unsubscribed and cleaned contacts, and archived contacts export separately
Import subscribed and unsubscribed contacts together, marking unsubscribes, so nobody who opted out is mailed again
Add cleaned (bounced) addresses to the new tool's suppression list
Verify your sending domain with the new tool before the first send, then move transactional mail first and campaigns after

The picks

#1 · 4.9 / 5

Unitpost

Best for apps that send product and marketing email

Campaigns, segments and topics on the same contacts and API as receipts and resets. Paid plans have unlimited contacts and are priced by sends; the free plan is 5,000 emails a month.

Pros

Contacts, custom fields and segments managed from your code
Transactional and marketing email on one list and one bill
Imports keep Mailchimp opt-outs as unsubscribed
A hosted MCP server and nine SDKs

Cons

The editor is simpler than Mailchimp's
Automations are in early access

Free plan: 5,000 emails a month, 200 a day, no card
Paid from: $10 a month for 20,000 emails
Priced by: Emails sent

Start free See pricing

#2 · 3.8 / 5

Customer.io

Best for messaging driven by product events

Messages triggered by what users do in your product, across email, push and SMS, with APIs for data in and a transactional API. No free plan.

Pros

Built on product events and user attributes
Server and mobile SDKs
Transactional API for every channel

Cons

No free plan outside the startup program
Priced by profiles, from $100 a month

Free plan: None; 12 months free for eligible startups
Paid from: $100 a month for 5,000 profiles
Priced by: Contacts

Visit Customer.io

#3 · 3.7 / 5

Loops

Best for SaaS teams that want a polished editor

Email built for SaaS, with campaigns, workflows and transactional sends, an editor non-technical teammates pick up fast, and a hosted MCP server.

Pros

An editor with real polish
Campaigns, workflows and transactional in one product
A hosted MCP server with OAuth

Cons

Priced by subscribed contacts
Transactional sends must use a template published in Loops

Free plan: 1,000 contacts and 4,000 sends a month
Paid from: $49 a month for up to 5,000 contacts
Priced by: Contacts

Unitpost vs Loops Visit Loops

#4 · 3.6 / 5

Brevo

Best for teams that want a full marketing suite

A marketing suite with a drag-and-drop editor, automation, a CRM, transactional email and SMTP, priced by email volume rather than contacts.

Pros

Priced by emails sent, not contacts
Transactional API and SMTP relay included
A hosted MCP server

Cons

Syncing app data takes more work than in SaaS-first tools
SMS and WhatsApp cost extra

Free plan: 300 emails a day
Paid from: $9 a month for 5,000 emails
Priced by: Emails sent

Unitpost vs Brevo Visit Brevo

#5 · 2.6 / 5

Kit

Best for creators moving a newsletter

Email marketing for creators, free up to 10,000 subscribers, with a v4 API, signed webhooks and a hosted MCP server. Not built for app email.

Pros

Free up to 10,000 subscribers
Tags, custom fields and sequences from the API
A hosted MCP server with OAuth

Cons

No transactional email or SMTP
One official SDK, for PHP

Free plan: Up to 10,000 subscribers
Paid from: $33 a month billed yearly, at 1,000 subscribers
Priced by: Contacts

Visit Kit

#6 · 2.6 / 5

Buttondown

Best for a developer's own newsletter

A small, API-first newsletter tool that writes in Markdown, with the API on every plan. A good fit for a changelog, not for app email.

Pros

API on every plan, with an OpenAPI spec
Signed webhooks
Markdown writing

Cons

No transactional email
No SDKs, by choice

Free plan: Up to 100 subscribers
Paid from: $9 a month for up to 1,000 subscribers
Priced by: Contacts

Visit Buttondown

Scores side by side

Product	Developer experience25%	Sync with your app20%	Pricing as you grow20%	Transactional too20%	Editor15%	Total
Unitpost	5	5	5	5	4	4.9
Customer.io	4	5	2	4	4	3.8
Loops	3	5	2	4	5	3.7
Brevo	3	3	4	4	4	3.6
Kit	3	3	2	1	4	2.6
Buttondown	3	4	2	1	3	2.6

How we scored

This list is for developers who run their product's email on Mailchimp and want an API-first tool: contacts created and updated from code, transactional and marketing mail on one list, and a bill that doesn't grow with every signup or unsubscribe.

Developer experience (25%). A clear REST API, current SDKs, readable errors and docs.
Sync with your app (20%). An API to create contacts and update their fields from your code, so segments follow product data.
Pricing as you grow (20%). The bill grows with what you send, not with every user who signs up.
Transactional too (20%). Receipts, resets and sign-in mail from the same tool and contact list.
Editor (15%). Non-developers can write, design and send without help.

Each product gets 1 to 5 per criterion, from its own pricing and docs pages. The total is the weighted mean, so changing a weight re-ranks the list.

Why Unitpost scored 4.9

Developer experience: 5/5. Bearer-token REST API, nine SDKs, a CLI and an MCP server, with idempotency keys on sends.
Sync with your app: 5/5. Contacts, custom fields, segments and topics through the REST API, SDKs and MCP server.
Pricing as you grow: 5/5. Unlimited contacts on paid plans; the bill follows sends.
Transactional too: 5/5. API, SMTP relay and campaigns share contacts, domains and suppressions.
Editor: 4/5. A visual editor and a code mode on the same document.

Checked November 2, 2026 against unitpost.com/pricing, unitpost.com/sms, registry.npmjs.org/unitpost.

Why Customer.io scored 3.8

Developer experience: 4/5. Track, Pipelines and App APIs, server and mobile SDKs, and a transactional send endpoint.
Sync with your app: 5/5. Built on your product's events and user attributes.
Pricing as you grow: 2/5. Priced by profiles, from $100 a month.
Transactional too: 4/5. A transactional API for email, push, SMS and WhatsApp.
Editor: 4/5. A visual editor and journey builder for marketers.

Checked November 2, 2026 against customer.io/pricing, docs.customer.io/ai/mcp/get-started/, docs.customer.io/integrations/api/customerio-apis/, docs.customer.io/integrations/directory/.

Why Loops scored 3.7

Developer experience: 3/5. A clean API, but transactional sends must use a template published in Loops.
Sync with your app: 5/5. An API and events built for syncing a SaaS user base.
Pricing as you grow: 2/5. Priced by subscribed contacts, so the bill grows with signups.
Transactional too: 4/5. Transactional API and SMTP, from templates published in Loops.
Editor: 5/5. The most polished editor here, aimed at SaaS teams.

Checked November 2, 2026 against loops.so/pricing, loops.so/docs/transactional, loops.so/docs/mcp-server.

Why Brevo scored 3.6

Developer experience: 3/5. A full API and SMTP relay, shaped by the marketing suite rather than built for developers first.
Sync with your app: 3/5. A contacts API with attributes, built for a marketing suite more than for product data.
Pricing as you grow: 4/5. Starter and Standard are sized by email volume.
Transactional too: 4/5. A transactional API and SMTP relay in the same account.
Editor: 4/5. A drag-and-drop editor with templates.

Checked November 2, 2026 against brevo.com/pricing/, developers.brevo.com/docs/mcp-protocol, help.brevo.com/hc/en-us/articles/7959631848850, help.brevo.com/hc/en-us/articles/360021533839, registry.npmjs.org/@getbrevo/brevo.

Why Kit scored 2.6

Developer experience: 3/5. A v4 REST API with API-key or OAuth auth, signed webhooks and a hosted MCP server, but one official SDK (PHP).
Sync with your app: 3/5. An API for subscribers, tags and sequences.
Pricing as you grow: 2/5. Subscriber tiers, from $33 a month billed yearly at 1,000.
Transactional too: 1/5. No transactional API or SMTP.
Editor: 4/5. An editor built for creators writing newsletters.

Checked November 2, 2026 against kit.com/pricing, developers.kit.com/mcp/kit-mcp.md, developers.kit.com/api-reference/overview.md, developers.kit.com/webhooks/overview.md.

Why Buttondown scored 2.6

Developer experience: 3/5. A REST API on every plan with an OpenAPI spec and signed webhooks; no SDKs or MCP server, by choice.
Sync with your app: 4/5. A REST API covering subscribers and emails.
Pricing as you grow: 2/5. Priced by subscribers, with add-ons on top.
Transactional too: 1/5. No transactional email or SMTP.
Editor: 3/5. Markdown writing, simple rather than visual.

Checked November 2, 2026 against buttondown.com/pricing, docs.buttondown.com/api-introduction, buttondown.com/features/api, docs.buttondown.com/api-webhooks-introduction.

Frequently asked questions

Do unsubscribed contacts count toward Mailchimp's bill?

Yes. Mailchimp counts subscribed, non-subscribed and unsubscribed contacts toward the contact limit and price tier; cleaned, pending and archived contacts don't. Archiving unsubscribes lowers the count but keeps them out of exports of active contacts.

Can I send transactional email with Mailchimp?

Only with the Transactional add-on, on Standard, Premium or the legacy Monthly plan. It's sold in blocks of 25,000 emails, and unused emails don't roll over. Tools on this list that include transactional email send it from the same contacts and bill as campaigns.

How do I keep unsubscribes when I leave Mailchimp?

Export the full audience, which includes unsubscribed and cleaned contacts, and import the unsubscribes flagged as such. On Unitpost, a contact imported with unsubscribed set to true stays unsubscribed, and an import never clears an existing opt-out.

Go deeper: Newsletter tools for SaaS · Marketing email · Unitpost vs Loops · Subscription topics

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