To replace MailerSend, send a few real receipts and password resets through the free tiers of two candidates, then compare delivery logs and bounce handling before moving your sending domain. Small developer-first providers and larger bundled platforms both do the job; the choice comes down to where your email is processed and how much else you want from one vendor.
Zoho's ZeptoMail page now says it's Zoho CPaaS, adding SMS, WhatsApp and voice to its email delivery, so a search for the old name lands on a wider product than you might expect. Mailchimp's transactional email is the old Mandrill job, now sold through Mailchimp. Neither change is bad, but both mean the name on an old comparison chart may not match what you'd sign up for today.
Advice first: test with messages you send for real
Don't move on a feature grid. If your messages are password resets, sign-in codes and receipts, what matters is whether they arrive quickly and whether you can see what happened when they don't. So send a handful of real templates through two shortlisted providers, then compare the logs side by side.
- Send to a few inboxes you control on different providers, including a work address.
- Force a bounce with an address you know doesn't exist and see how each tool reports it.
- Check how long logs are kept and whether you can search them by recipient.
- Try both the API and SMTP routes if your app uses both.
- Look at how each one handles webhooks for bounces and complaints, since your app may need to act on them.
Give each provider the same templates, the same recipients and the same few days. Then ask one plain question: when a message went wrong, which dashboard told you why faster? That answer matters more than any feature you won't use.
Small and developer-first, or part of a larger platform
Developer-first and small providers. Plunk says it's open source and self-hostable, so you can run it on your own servers. Lettermint offers an API, SMTP and SDKs, per its own site. MailPace describes itself as a transactional email API for developers. Maileroo pitches delivery logs you can query. Emailit offers transactional and marketing email through one REST API.
Several rows in that group are EU-hosted or run by small teams, which matters if your customers ask where their email is processed. Data rules vary by country and contract, so check the vendor's terms and ask an adviser rather than treating a hosting page as the answer.
Larger bundled platforms. Elastic Email calls itself a modern email communication platform for growing businesses. Mailchimp Transactional is sold through Mailchimp itself, for confirmations and shipping updates. Zoho CPaaS (ZeptoMail) now covers four channels from one platform. These suit teams that want one vendor for more than receipts.
Whichever group you lean towards, check two practical things before shortlisting: whether the provider supports the sending libraries your app already uses, and whether its dashboard lets a non-developer look up a single message when a customer asks where it went.
Run a transactional email service that fits one of these groups? Put it forward for this page.
If you're comparing the bigger developer names too, my Mailgun alternatives and Postmark alternatives lists cover different ground.
The eight services compared
| Tool | Free option | Group on this page |
|---|---|---|
| Elastic Email | Free trial | Larger bundled platform |
| Emailit | Free plan | Developer-first, small |
| Lettermint | Free plan | Developer-first, small |
| Mailchimp Transactional | Not stated | Larger bundled platform |
| Maileroo | Free plan | Developer-first, small |
| MailPace | Free plan | Developer-first, small |
| Plunk | Free, open source | Developer-first, small |
| Zoho CPaaS (ZeptoMail) | Not stated | Larger bundled platform |
All eight, A to Z
Quotation marks mark each vendor's own words; the list is in no particular order.
Elastic Email
Best for: Running campaigns and transactional messages from one account.
Emailit
Best for: Keeping sending in Europe, from what it calls its "own EU data centre".
Lettermint
Best for: Teams that need email to stay in the EU, as it runs "exclusively in the EU".
Mailchimp Transactional
Best for: Event-based messages, email or SMS, "built to scale with your business".
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Maileroo
Best for: Sending both transactional and marketing mail over SMTP or API.
MailPace
Best for: Password resets, OTP codes and notifications through a "privacy-first" API.
Plunk
Best for: Running transactional email, campaigns and automations against "one contact list".
Zoho CPaaS (ZeptoMail)
Best for: Keeping ZeptoMail's sending underneath, as the platform is "built on ZeptoMail's proven email delivery infrastructure".
Moving your sending domain without losing mail
Once you've picked, the move itself is where mail goes missing. Plan it like a small release, with a rollback.
- Add the new provider's DNS records first. Set up SPF, DKIM and any return-path record before you switch any traffic.
- Send a small share of traffic first. Route one message type, such as receipts, through the new provider while the rest stays put.
- Watch bounces and complaints daily. Compare them with what you saw before the move.
- Find the hidden senders. Update SMTP settings in plugins, forms and third-party tools that send as your domain.
- Move the rest, then tidy up. Remove old DNS records and API keys only once nothing is sending through them.
Keep your old account open for a short overlap so you can roll back if something looks wrong, and tell support staff the date so they know where to look if a customer says a reset never arrived.
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Frequently asked questions
What's the difference between an email API and an SMTP relay?
An API sends mail through HTTP requests from your code. An SMTP relay accepts mail the way an email server does, which suits older apps and plugins. Many providers offer both.
Should transactional and marketing email share a provider?
They can. Keeping them on separate subdomains means a problem with a newsletter is less likely to affect password resets.
Does EU hosting make me compliant?
Not on its own. Where email is processed is one part of data protection, and the rules vary. Check the vendor's terms and ask an adviser.
Why aren't SendGrid or Amazon SES here?
They have their own pages on this site, so this list sticks to other options.
Do I need a dedicated IP address?
It depends on your volume. Ask each vendor whether they'd suggest a dedicated address for your sending and what warming it up involves.
How long should I run two providers side by side?
Long enough to see normal traffic, including a busy day. A week or two of real sending tells you more than any test message.
