April 17, 2023

5 Best Transactional Email Services for Marketers (2024)

Reading time about 12 min

Is using a transactional email service top priority for marketers? Compared to marketing emails, a single transactional email can have a significant impact on business.

If a customer doesn’t get your newsletter, they might miss your latest sale. But if a customer doesn’t receive a transactional message, you’ll likely lose them as a customer.

For any online business, transactional emails are critical in many ways. They’re not only vital for the success of transactions but also foster a positive customer experience and brand loyalty.

That’s why a transactional email service that guarantees your messages get delivered is so important. To help you make the right choice, we vetted an extensive list of tools and picked the five best transactional email service providers for various business goals and budgets.

What is a transactional email service?

A transactional email service is an application that sends automated, business-to-user emails triggered by specific events on a website or in an app. These emails are instant and cannot be scheduled. They’re sent in real time as the trigger events happen.

The nature of transactional emails requires fast delivery to the inbox, dynamic personalization, and high security protocols.

To send out these messages, a transactional email service typically offers two methods: SMTP relay and transactional email API. These methods allow for sending large email volumes daily and ensure excellent deliverability of critical customer updates.

Maybe terms like SMTP or API sound too techy. Don’t sweat it! Not all transactional email providers require coding skills to set up and use their services. You can pick a platform with a user-friendly interface and send transactional emails from there.

Transactional email services vs. email marketing tools

Don’t all email marketing platforms offer transactional email services? Not really…

Email marketing software allows you to send marketing messages, like newsletters, abandoned cart emails, drip campaigns, bulk emails, and other promotional emails to your subscribers.

Its functionality does not include transactional email services by default. However, some email marketing platforms like Brevo offer SMTP relay services and transactional email API as part of their toolkit.

Related: Best SMTP Servers for Email Marketers

Do you need a transactional email service?

Every organization that sells services or products sends transactional emails to their customers. They’re a vital part of customer support and service. So the short answer is “yes.”

Below are some most common use cases for transactional email services. Discover more transactional email examples here.

Ecommerce stores

Ecommerce stores are the most avid users of transactional email services, and for good reason. You can hardly imagine an online buying process without instant order notifications, like the one below:

a transactional email example with shipping confirmation

Order confirmation emails are probably the most popular type of transactional message. Think of them as notification emails Other commonly used types of transactional emails include:

  • Invoices and receipts
  • Shipping information and tracking
  • Return updates

SaaS companies

SaaS businesses also send transactional emails. After signing up, SaaS customers receive welcome emails, e-receipts, account notifications, password resets, transaction failure notifications, and subscription expiration messages.

One common example of a transactional email in the SaaS industry is the trial expiration email. Squarespace triggers an expiration message 24 hours before a user’s free trial ends: 

A transactional email about a free trial expiring

Brick-and-mortar businesses

Another category of businesses that benefit from transactional emails is brick-and-mortar service organizations, like gyms, clinics, hotels, etc.

If people interact with you online, e.g., book appointments via a website, it’s good practice to send confirmations and other transactional messages to communicate important information and support the customer journey. 

a transactional email confirming a booking for an offline event

Starting to see how every business with an online presence can use transactional email software? The next question is — how do you find the right one?

Top transactional email services at a glance 

  1. Brevo
  2. Mandrill
  3. Mailgun
  4. SendGrid
  5. Mailjet

5 Best transactional email services

In our list, we’ve compiled the best service providers for any need. Some of them handle both promotional and transactional emails under one roof, others are dedicated SMTP relay services focusing on transactional email sending.

1. Brevo

transactional email

Brevo offers one of the best transactional email service. It gives non-tech users access to a full range of intuitive transactional email functionalities.

That, and the suite of email marketing, live chat, Sales Platform, SMS, WhatsApp, and other tools make it the best transactional email service for growing businesses looking to manage all customer communications and marketing campaigns in one place.

Brevo Transactional Email highlights:

  • Flexible sending options: Brevo offers a range of methods for sending transactional emails, including SMTP relay, transactional email API, automation workflows, and ecommerce plugins.
  • Transactional email plugins: Custom-built transactional email plugins for Shopify, WordPress, WooCommerce, nopCommerce, Magento, Prestashop, and other ecommerce platforms are all available for free.
  • No-code setup: No coding skills are needed to set up and use Brevo’s transactional email service. 
  • Drag-and-drop email builder: Quickly and easily design professional transactional emails to match your branding. 
  • Email templates available: No need to start from scratch — just customize ready-made templates.
  • Transactional SMS: Similar to emails, Brevo’s transactional SMS can be set up through a variety of methods, including API, marketing automation, or plugins. 
  • Unlimited log retention: Brevo keeps the entire log history unless otherwise specified.
  • Dedicated deliverability team: Our email deliverability experts will assist you in achieving excellent email deliverability. 
  • Dedicated IPs: To enhance your sender reputation and avoid recipients’ spam folders, you can purchase dedicated IP addresses.
  • All-in-one marketing platform: In addition, Brevo provides a full email marketing suite, live chat, SMS marketing, CRM, and other tools.
  • GDPR compliance: If a contact doesn’t subscribe to your marketing emails, they’ll receive only transactional emails.

Brevo Transactional Email pricing

So how much does transactional email software cost?

Brevo offers free transactional email services. You can send up to 300 emails per day free forever. Paid plans start at $15/month for 20,000 monthly transactional emails. That’s it — no setup fees, no license charges.

2. Mandrill


Mandrill, or Mailchimp Transactional Email, is a Mailchimp add-on for one-to-one transactional email sending.

Built as a delivery API for transactional emails, Mandrill has been a separate product for years. After merging with Mailchimp a few years ago, Mandrill is no longer a stand-alone service. Only Mailchimp users can purchase Mandrill now. 

Mandrill pros

  • Transactional API and SMTP integration 
  • Mobile app
  • Detailed API documentation
  • Long-established sender reputation
  • Dedicated IP addresses
  • ISP feedback loops
  • Complete marketing automation toolkit

Mandrill cons

  • It’s sophisticated and built for tech-savvy users. If you don’t know how to work with API documentation, Mandrill might be too complicated for you.
  • A Mailchimp plan is required to access transactional email services. Mandrill is an add-on available on Mailchimp’s Standard plan and above.
  • If you aren’t a paid user of Mailchimp, you can’t try its transactional email services for free.

Given the primary focus on developers and its pricing model, Mailchimp Transactional API is the right choice for teams that have already been using Mailchimp for some time and have tech-savvy specialists to work with its transactional API.

Mandrill pricing

Only paid Mailchimp users can access Mandrill. After purchasing one of Mailchimp’s marketing plans, transactional email credits are purchased in blocks of 25,000 emails. The first 20 blocks come at a price of $20 each.

Standard plan users can test Mandrill with 500 emails for free.

3. Mailgun


Mailgun is a dedicated transactional email software. Similar to Mandrill, it’s built for advanced transactional email senders. To add email marketing functionality, you’ll have to get a Mailjet subscription as the platform was acquired by Mailgun in 2021.

Mailgun pros

Mailgun is a great transactional email service for many reasons:

  • HTTP API and SMTP endpoint
  • Integrations with a wide range of CMS solutions and frameworks
  • Deliverability Service that consults users experiencing issues with email deliverability
  • Send time optimization, where the software holds an email until a recipient engages with their inbox so the message appears at the top of the list to boost email engagement.
  • Dedicated IPs
  • Webhooks to collect email message data with webhooks
  • Multi-user access

Mailgun cons

  • The learning curve is steep. Non-tech users might find it too advanced a solution.
  • Log retention is limited to a maximum of 30 days. On cheaper plans, log retention is only five days.
  • Support options are limited and wait times can be long.
  • Due to its flexibility with data handling, Mailgun’s reputation isn’t the best. It’s become a go-to solution for spammers and scammers.

Mailgun pricing

Mailgun doesn’t offer a free plan. In the first month, you can send up to 5,000 free emails. Mailgun pricing starts at $35/month for 50,000 emails, five days of log retention, and email address validation access. To access dedicated IP pools, SAML authentication, and send time optimization, you’ll need the top-tier plan, starting at $90/month.

4. SendGrid 


SendGrid is transactional email and marketing software. Twilio SendGrid Email API is the name of its dedicated transactional email service. 

SendGrid Email API is a powerful tool built for developers, but one of the most technical email platforms on the market.

To access email marketing features, you can purchase one of SendGrid’s Marketing Campaigns Plans that come as separate products.

SendGrid Email API pros

  • API documentation and open-source libraries in seven languages
  • ISP feedback loops. Users receive complaint data in the form of feedback messages.
  • Insightful analytics on account performance
  • Email delivery optimization tools — SPF records, custom DKIM, and suppression management. 
  • Free SMTP Relay & APIs 
  • Dynamic transactional email templates
  • Dedicated IP addresses

SendGrid Email API cons

  • Again, the learning curve is steep. SendGrid Email API is a sophisticated solution for tech pros, but it takes a lot of time and effort for new users to make it through the setup process.
  • Multi-user access is only available on top-tier plans. To collaborate with teammates on email campaigns, you’ll need to pay a minimum of $89.95/month.

Related: 5 Best SendGrid Alternatives for Transactional Email

SendGrid Email API pricing

SendGrid’s SMTP Relay is included in its forever-free plan, letting you send 100 emails/day, use delivery optimization tools, and access email analytics. From $19.95/month, you can send up to 50,000 transactional emails.

5. Mailjet


Mailjet is a simple email service for marketers and developers alike.

Although Mailjet has been acquired by Mailgun, the platform still offers its own SMTP server. While Mailgun is designed for developers, Mailjet offers intuitive tools for non-technical users. It’s a good choice for beginners and low-budget teams.

Mailjet pros

  • User-friendly, no coding tools
  • Their support team helps with deliverability challenges and optimizing email routing.
  • Dedicated IPs
  • SMTP relay, email APIs and webhooks are included in Mailjet’s forever-free plan.
  • Email marketing features also available
  • Transactional SMS sending
  • ISO 27001 certified and GDPR-compliant

Mailjet cons

  • Mailgun is built with marketers in mind, not developers. So if you’re looking for great API documentation, you’d better turn to Mailgun. 
  • While offering advanced features such as marketing automation, Mailjet lacks some critical tools like a CRM system.

Mailjet pricing

Mailjet’s free plan includes 6,000 emails/month, with a limit of 200 emails per day. Paid plans start at $15/month for 15,000 monthly emails. SMS credits are purchased separately. 

What is the best transactional email software?

Depending on the goals and resources you have, different transactional email services may suit your business.

Is an SMTP relay service all you’re looking for? Then Mailgun (for developers) or Mailjet (for less tech-savvy specialists) will suffice. 

Do you need a complete marketing automation platform with transactional email sending functionality? Then, Brevo could be the right choice. It’s the most cost-effective solution with a free SMTP relay service and a solid marketing automation toolkit.

Test-drive Brevo’s transactional email service

Free SMTP server for up to 300 emails/day, email API for developers, transactional email templates, and unlimited log retention.

Open my free Brevo account now >>

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