If your software needs to send email, you have two main ways to connect it to Mailpro: SMTP, the long-established mail protocol, or an HTTP API. Both deliver the same email through the same infrastructure. The difference is how your system talks to Mailpro, and what else it can do along the way.
The short answer
- Choose SMTP when you use existing software, such as a hotel property management system, WordPress, or an accounting package, that already has an outgoing mail setting.
- Choose the API when you are writing code, need to manage contacts as well as send, or want structured delivery data back in your application.
Side by side
| SMTP | API | |
|---|---|---|
| Set-up | Enter server, port, username and password in your software. | Call HTTPS endpoints with an API key from your code. |
| Skills needed | Basic IT administration. | A developer. |
| Best for | Off-the-shelf systems and websites. | Custom apps, portals and integrations. |
| Beyond sending | Sending only. | Contacts, lists, campaigns and status queries. |
| Feedback | Reports in the Mailpro dashboard. | Dashboard, API responses and webhooks. |
Three Antiguan scenarios
A boutique hotel in English Harbour
The hotel’s property management system has an SMTP setting and no developer on staff. Entering Mailpro’s SMTP details takes fifteen minutes, and confirmations stop landing in spam. SMTP is the right choice.
A tour-booking start-up in St. John’s
The team is building its own platform. It needs to send confirmations, add customers to lists, and know immediately when an email bounces so it can text the customer instead. The API, with webhooks, fits better.
An international bank
The core banking system sends notifications by SMTP, while a new client app uses the API for onboarding emails. Using both is common, and all traffic shows up in the same Mailpro account.
Things that are the same either way
- Deliverability: both routes use the same sending infrastructure. In Mailpro’s own customer survey, email deliverability was rated 9.6/10.
- Authentication: you still need SPF, DKIM and DMARC on your domain; see email authentication explained.
- Security and hosting: both are encrypted with TLS and processed in Switzerland, outside US jurisdiction. That supports your security obligations under section 8 of Antigua and Barbuda’s Data Protection Act, 2013.
- Consent: promotional messages need consent under the Act regardless of how they are sent.
- Pricing: Mailpro charges by messages sent, whichever route you use.
Performance and reliability
SMTP involves a short conversation between servers for each message, while an API call sends a message, or a batch, in one HTTPS request. For a few hundred confirmations a day, the difference does not matter. For high-volume platforms, the API is usually more efficient and easier to monitor. For a deeper technical comparison, read SMTP relay versus email API.
Questions to ask before you decide
- Does the software already support SMTP? If yes, and you only need to send, start there. You can move to the API later.
- Who will maintain the integration? An API integration is code that someone must keep updated. If your developer is a contractor based overseas, make sure the integration is documented.
- Do you need to react to events? If a bounced confirmation should trigger a text message to the guest’s phone, the API with webhooks is the tool.
- How sensitive is the content? Both routes are encrypted, but you control what goes into each message. Avoid sending full account numbers or passport details by email at all.
Migrating from your web host’s mail server
Many Antiguan websites still send through their hosting company’s shared mail server. Moving to Mailpro by SMTP is usually the quickest win: change the outgoing server settings, add SPF and DKIM records to your domain, send a test, and watch the delivery reports for a week. If you later rebuild the site, switch to the API at that point.
Next steps
Go with SMTP: set up Mailpro’s SMTP server. Go with the API: start with the email API for Antigua and Barbuda.