Choosing the Best Transactional Email Service

For the last month or so, I spent my days testing popular transactional email services.

I played around with dozens of tools on the market and picked out 8 best-performing providers. I reviewed all of them based on pre-selected criteria. Moreover, I scraped through the reviews on software catalogs to find out what other users think about these tools. 

So, let’s dive into the list of 8 best transactional email services. 

8 Best transactional email service providers

• Mailtrap for businesses and individuals looking for a reliable infrastructure to send transactional, bulk, or marketing emails and achieve high deliverability rates. 
• Mailgun for businesses looking for a two-in-one solution for transactional and marketing services;. 
• SendGrid for businesses of all sizes looking for a scalable solution.
• Amazon SES for businesses with strong dev teams looking for an affordable solution and already using AWS infrastructure. 
• Mailchimp Transactional Email (formerly Mandrill) for businesses already using Mailchimp as their marketing platform.
• Brevo (formerly Sendinblue) for individuals and small to medium businesses looking for versatile integration options, not just API or SMTP.
• Postmark for businesses looking for a volume-based pricing structure, not a feature-based one. 
• SendPulse for businesses requiring a comprehensive approach to their transactional and marketing communications. 

Best transactional email services: selection criteria 

The best-performing transactional email service providers must satisfy specific criteria: 

• High email deliverability rates. For example, transactional emails, such as password reset or confirmation emails, should always land in inboxes. 
• Stable infrastructure with close to zero downtime. This includes backup servers, network monitoring, and high deliverability speed. 
• Email analytics and reports. This will help you track the performance of your emails with popular metrics such as open and click rates, bounce rates, spam complaints, and delivery rates. 
• Smooth integration with your app or project. Integration options should include SMTP and API, as well as SDKs for popular programming languages. All of that should be paired with extensive and helpful documentation. Optional but useful integration options include plugins, browser extensions, etc. 
• Scalability. The chosen platform should offer easy scaling options, such as purchasing additional emails or upgrading the plan. And, of course, deliverability should remain the same even with increased sending volumes. 
• Transactional email templates. This isn’t a must-have feature, but it’s pretty useful, especially for maintaining consistency in all your emails. 

Best transactional email services

Disclaimer: The prices and product ratings are up-to-date at the time of writing and could be different when you’re reading this blog post. Also, all the included prices are for monthly subscriptions and can differ for annual plans. 

Mailtrap

Mailtrap is an email delivery platform that has both Email Sending and Email Testing solutions. For this blog post, I’ll focus on Email Sending. 

Email Sending is an email product with high deliverability rates by design. It has Email API and SMTP Service and ready-made SDKs for Node.js, Ruby, PHP, Python, and Elixir. 

Creating the account is quite straightforward. You just go to the signup page, choose the registration method, and fill out the empty fields. 

Once the account was ready, I went to Sending Domains to add and verify my domain. This step is necessary to confirm the ownership of the domain and set up authentication protocols. The latter helps with deliverability (and is now a requirement from Google and Yahoo!). 

Read this article or watch the in-app video for detailed instructions on adding and verifying the domain. 

After the domain was verified, I was able to start sending the emails. 

You have SMTP and API integration options with sample configurations for popular programming languages and frameworks. Check out this playlist to learn how to integrate Mailtrap and send emails with API or SMTP. 

Mailtrap also has migration guides if you’re migrating from another solution. You can check out how to migrate from SendGrid, Mailgun, Mailchimp Transactional Email, and Amazon SES. To migrate smoothly and gradually, you can use the ActionMailer Balancer gem if your app is built in Ruby. 

One of the most important and useful features is the fact that Mailtrap offers separate streams for transactional and bulk emails. This helps with maintaining high deliverability rates. 

As a transactional email provider, Mailtrap also has transactional email templates. These can be created and stored within the platform and referenced later through API calls. Templates operate on the handlebars engine and support variables. 

Another handy feature is actionable analytics with drill-down reports and helicopter-view dashboards. The drill-down reports are available for email categories and mailbox providers. You can filter the stats based on categories, providers, domains, and streams. 

Additionally, you can track unique open rates, delivery rates, click rates, bounce rates, and spam complaints. 

Features 

• Separate streams for transactional and bulk emails
• SMTP, API, and SDKs
• In-depth stats with actionable analytics
• Transactional email templates 
• Up to 60 days of email logs
• Deliverability alerts to catch any unexpected sending issues if they occur
• Suppression management
• Webhooks
• Dedicated IP addresses with automatic warmup for high-volume senders
• Email Campaigns (available soon)

Pros

• Supportive and helpful customer service regardless of the pricing plan
• 99.9% server uptime
• Clear and intuitive in-app interface
• High deliverability rates
• Easy-to-read dashboards
• Essential features available for all pricing plans
• Can be scaled by changing the plan if your email volumes increase over time 

Cons

• Lacks plugins and ready-made integration options for non-dev teams

Pricing 

Free tier: 1,000 emails/month 

Paid plans: from $10 for 10,000 emails/month 

Additional 1,000 emails: $1 and less. 

Visit the pricing page for more details on available plans and features. 

Software catalog ratings 

G2: 4.8 ⭐

Capterra: 5.0 ⭐ 

Mailgun

Mailgun is a popular platform for sending, tracking, and optimizing different types of transactional emails and marketing campaigns. 

Mailgun recently introduced a product suite consisting of Mailgun Send (good ol’ sending solution), Mailgun Optimize (email deliverability tool), and Mailgun Validate. 

We’ll be concentrating on Mailgun Send. 

The setup process is quite straightforward. After creating the account, you have two options: 

• Add and verify a custom domain (to send in production)
• Use a sandbox domain created by default (to test the features, shouldn’t be used in prod)

In terms of sending the emails, you can use either API or SMTP methods. Both have instructions and code samples to make the integration process easier. 

Mailgun Send features an intuitive dashboard with analytics to measure the progress of your emails. 

There’s also the ability to create and store the templates on the platform. You get a drag-and-drop editor and an HTML editor. I found the templates a bit limited for marketing campaigns, but they were sufficient for simple order confirmation emails or other transactional notifications. 

Another useful feature is the ability to switch between the US and EU regions, with each having different SMTP and API endpoints (available in paid plans). 

Similar to Mailtrap, Mailgun Send requires technical expertise to set up. However, I found Mailtrap’s docs a bit easier to understand and follow. Check out this blog post for more comparisons of Mailgun and its competitors. 

Features 

• Send time optimization 
• Email validation (add-on for Foundation plan and included in Scale)
• API and SMTP integration, as well as third-party integrations with CRM, CMS, E-commerce, and other platforms
• Email templates
• Email tracking and analytics 

Pros 

• The ability to validate emails without switching to another platform 
• A wide selection of third-party integrations 
• High deliverability rates 
• Allows for (and recommends) using subdomains for different types of emails 

Cons

• Slow support 
• You can’t search logs by email content (searching by tags is supported, though)
• The platform has several bugs (probably due to the addition of new features) 

Pricing

Free tier: No 

Free trial: 30 days (for the Foundation plan), 5,000 free emails 

Paid plans: from $35 for 50,000 emails/month (or pay-as-you-go option with first 1,000 emails free and $1 per 1,000 emails after that) 

Additional 1,000 emails: $1 and less. 

Software catalog ratings

G2: 4.3 ⭐

Capterra: 4.3 ⭐ 

SendGrid

SendGrid is one of the most popular transactional email service providers, but it also provides an Email Marketing tool with marketing automation, segmentation, and other useful features. 

While Email Marketing is suitable for diverse teams, Email API is geared toward developers (similar to most transactional service providers out there). The documentation can be hard to understand even with technical expertise. 

The good thing about SendGrid Email API is its analytics feature. You’ll have a hard time finding an aspect of your emails you can’t track and analyze with this platform. This has a flip side, too – there’s a steep learning curve while setting up and understanding all the dashboards and stats. It also lacks a unified dashboard that would show an overall overview of the email performance. This makes the analytics a bit scattered. 

The useful features also include dynamic templates, SMTP, API, and third-party integrations, suppression management, email validation API, and email testing (included in higher-paying plans). 

One thing to keep in mind is that some of the essential features are reserved only for higher-paying plans. For example, the response time from the support team and the type of support varies based on the plan. 

Read more about SendGrid and its alternatives here. 

Features 

• SMTP, API, and third-party integration options
• Diverse dashboards and stats for in-depth analytics 
• Email validation API 
• Dynamic email templates with drag-and-drop and HTML editors

Pros 

• Easy to connect to other platforms and services 
• Comprehensive integration guides, tutorials, and API documentation 
• Continuous sender reputation monitoring

Cons

• Some of the essential features reserved for higher-paying plans 
• Slow support 
• Occasional downtimes 

Pricing

Free tier: 100 emails/day 

Free trial: Yes 

Paid plans: from $19.95 for 50,000 emails/month 

Additional 1,000 emails: $1.33 and less 

Software catalog ratings

G2: 4.0  ⭐

Capterra: 4.2 ⭐ 

Amazon SES

Amazon SES or Simple Email Services is one of the most cost-effective options for sending transactional emails. It’s particularly handy for those who are already using AWS infrastructure and EC2.

If it’s your first time signing up with AWS, you’ll have to fill out personal details, including your address, credit card, and phone number. Then you’ll need to add and verify your domain (similar to other services). 

Amazon SES used to have a very generous free tier with up to 62,000 free emails/month. However, they changed their pricing structure on August 1, 2023. With the revised structure, users get access to 3,000 so-called message charges for the first 12 months. These charges include inbound and outbound emails and Virtual Deliverability Manager. 

After the free trial, you’ll pay $0.10 per 1,000 emails (additional fees apply).

Note: Even with the free trial, you pay data transfer fees and for any add-ons you choose to purchase. 

Amazon SES offers a dedicated IP (for an additional fee), reputation metrics, basic analytics, suppression management, and email templates. It’s a reliable and robust service to send marketing or transactional messages, but it’s definitely suited for more technical teams looking for basic email functionalities.

For more details on Amazon SES and its alternatives, read this blog post. 

Features 

• SMTP server, robust API, and SDKs
• Reputation monitoring
• Virtual Deliverability Manager with dashboards and optional automatic optimization 
• The ability to send bulk and transactional emails 
• The ability to choose the region for the servers

Pros 

• More affordable compared to its competitors 
• Robust security features and spam protection 
• Easy to scale 
• Supports inbound messages 

Cons

• Slow customer service 
• Analytics are hard to set up 

Pricing

Free tier: 3,000 message charges/month (for the first 12 months)

Free trial: No

Paid plans: Pay-as-you-go pricing model with $0.10 per 1,000 emails (additional fees apply).

Software catalog ratings

G2: 4.3  ⭐

Capterra: 4.7 ⭐ 

Mailchimp Transactional Email (formerly Mandrill)

Mailchimp Transactional Email isn’t a standalone tool but rather a transactional-oriented portion of the Mailchimp product. It’s mostly suitable for Mailchimp users as it can’t be used without a Mailchimp Marketing Platform subscription (Standard, Premium, or Legacy). 

The setup process is similar to other transactional providers, but the UI is a bit outdated. Regardless, Transactional Email still has decent analytics, inbound routing, webhooks, suppression management, and customizable settings. 

While I wouldn’t recommend this tool if you only need a transactional email delivery service, it performs quite well as a Mailchimp add-on. 

 Features 

• SMTP and API integration 
• Customizable sending domain settings 
• Analytics with the ability to create comparisons 
• API logs 
• Webhooks 
• Suppression management (Rejection Lists) 

Pros 

• Test mode to test the setup before sending emails in production
• Email alerts for reputation drop or webhook failure
• Sender reputation tracking 
• A/B testing (Split Tests) for transactional emails 
• Code editor to create email templates 

Cons

• Can’t be used without Mailchimp Marketing Platform 
• Costlier compared to its competitors 
• Outdated UI 

Pricing

Free tier: None

Free trial: Yes (500 emails)

Paid plans: $20 for 25,000 emails/month (has a block-based pricing structure, price per block is lower for high-volume senders) + Marketing Platform subscription (from $20) 

Additional 1,000 emails: N/A

Software catalog ratings

G2: 4.2 ⭐

Capterra: 4.5 ⭐ 

Note: Most reviews are for Mailchimp overall, not specifically for Transactional Email. 

Brevo (formerly Sendinblue)

Brevo (formerly Sendinblue) is a CRM suite that has a Marketing Platform, Conversations, Sales Platform, and Transactional Email products. 

Getting started with Transactional Email is fairly easy – you’re taken to a simple three-step wizard that helps with setting everything up. 

Integration options include SMTP and API. You’ll find examples for Postfix and PHP in the wizard itself. Moreover, Brevo Transactional Email has official SDKs for multiple languages and frameworks. 

One thing to note is that Brevo allows you to send emails without adding and verifying the sending domain. You can use a free email address. I strongly recommend against it as it will negatively impact your deliverability, especially once Google’s and Yahoo’s new sender requirements are enforced. 

So, if you choose Brevo as your transactional email platform, make sure you add a sending domain and authenticate it with DKIM, SPF, and DMARC. 

The interface is really user-friendly, and so is the documentation. However, some parameters are located in the profile menu, not under Transactional as I expected. This can be a bit confusing when you’re getting started. 

With that being said, Brevo Transactional Email is an affordable solution, especially if you’re already using Brevo as your marketing tool. 

Features 

• Transactional email templates with code and drag-and-drop editors 
• Email tracking and analytics
• SMTP relay, API integration, and plugins 
• Customized log retention 

Pros 

• Volume-based pricing structure with all the features available in all tiers
• Easy to set up and use 
• Generous free tier 

Cons

• Limited design options for email templates 
• Some essential features are hidden in the menus 

Pricing

Free tier: 300 emails/day 

Free trial: No

Paid plans: from $15 for 20,000 emails/month for Transactional Email separately, but you can also send transactional emails with email credits in marketing plans.

Additional 1,000 emails: N/A

Software catalog ratings

G2: 4.6  ⭐

Capterra: 4.5 ⭐ 

Postmark

Similar to Mailtrap, Postmark is a platform that enables users to send bulk and transactional emails. They, too, have separate streams for both. 

While Postmark’s interface is quite simple, the naming of the features is a little different from other platforms. For example, the default page is Servers, which act as projects and have no connection with actual servers. This can be a bit confusing in the beginning, but they do have an explanatory video and a getting started guide. 

Within each Server (or project), you’ll find three streams: Broadcast (bulk), Inbound, and Transactional. 

Transactional Stream comes with SMTP and API integration, topped with official and community libraries for various programming languages and frameworks. Postmark also offers plugins and various integrations through Zapier. 

One of the notable benefits of Postmark is its pricing structure. It charges you based on the number of emails you send – not the specific features. However, keep in mind that dedicated IPs should be purchased separately if needed (costs $50 per IP per month and is available for users sending more than 300,000 emails/month). 

Features 

• Sandbox server for testing their bounce API 
• Separate streams for transactional and broadcast emails  
• Comprehensive and well-structured documentation 
• Different types of webhooks 
• Suppression management 
• Analytics 

Pros 

• High deliverability rates 
• Wide selection of libraries and integration options
• Email templates 
• Well-documented API 

Cons

• Dedicated IP isn’t included in the pricing 

Pricing

Free tier: 100 emails/month 

Free trial: No

Paid plans: $15 for 10,000 emails/month 

Additional 1,000 emails: $1.8 and less 

Software catalog ratings

G2: 4.6 ⭐

Capterra: 4.8 ⭐ 

SendPulse

SendPulse is a marketing automation platform that comes with the ability to send transactional emails. It’s comparable to SendGrid and Brevo. 

When you first sign up, you have to create a User Profile. It’s a simple form that asks for your business email address, your usage of the platform, and your emailing practices. 

What stood out to me about SendPulse was their pricing. Their free plan is the most generous on this list, and the paid plans are really affordable as well. And if you’re using their platform to communicate with your subscribers and customers (via email or social media chatbots), you won’t need a separate plan to send transactional emails. 

You get a simple email-sending solution to send your confirmation or welcome emails with API and SMTP integration, mailing history, analytics, and unsubscribe management. 

In addition, SendPulse has official SDKs for multiple programming languages and ready-made integrations for WordPress, Salesforce, Shopify, and other platforms. 

Features 

• Analytics to track the performance of your transactional emails 
• Domain authentication with SPF and DKIM
• SMTP, API, SDKs, and third-party integrations
• Custom tracking domain 
• Unsubscribe management 

Pros 

• Affordable pricing structure with pay-as-you-go option 
• Simple interface 
• Quick and responsive customer support 

Cons

• The documentation could be better 

Pricing

Free tier: 12,000 emails/month 

Free trial: No

Paid plans: from $8.69 for 25,000 emails/month (for subscription) and from $16.60 for 10,000 emails/month (for pay-as-you-go option) 

Note: These prices are approximate. SendPulse pricing is shown in Euros, so we included estimates in USD. 

Additional 1,000 emails: N/A

Software catalog ratings

G2: 4.6 ⭐

Capterra: 4.6 ⭐ 

Are there free platforms for transactional emails?

Yes and no. Technically, you can send transactional emails from free email accounts, such as Gmail, Yahoo!, AOL, Outlook, and others. 

However, these providers have strict limits on sending volume and minimal ways of controlling your sender reputation and deliverability. 

As mentioned above, Google and Yahoo! are enforcing new sender requirements from February 2024. They require each sender to have an authenticated sending domain, PTR records, and low spam rates, among others. These requirements are even lengthier for high-volume senders. 

So, even small amounts of transactional emails from free accounts could land you in the spam folder. 

That’s why you need a reputable email service provider with a robust infrastructure. And luckily, most of them have free tiers for low-volume senders. With these, you also get access to email builders, analytics, templates, and other useful features. 

Using Gmail API and SMTP to send emails

A viable alternative is to send transactional emails with Gmail API or SMTP. Even then, it’s better to opt for a Google Workspace account (starting from $6 per user/per month). 

With Gmail API and SMTP, you can send different types of emails, automate email sending, manage your Gmail mailbox, and so on. Check out our detailed guide on sending emails with Gmail API and read the official docs. Watch the following tutorials to learn how to send emails with Gmail SMTP: 

• Send Email in Python with Gmail 2023
• Laravel Tutorial: Send Emails Using Gmail SMTP
• Send Email from Windows PowerShell with Gmail
• Spring Boot – Send Email via Gmail SMTP 

What’s next

Now you have the information and resources to choose the best transactional email service. Apart from the defined criteria, you may also want to consider the following factors:

• Payment preferences. Do you prefer to have a monthly plan or a pay-as-you-go option? Are you looking for monthly or annual billing? 
• Types of emails you’ll be sending. Will you be sending only transactional emails or bulk and marketing emails as well? For the former, choose a platform that focuses on transactional emails. For the latter, consider providers that offer both, especially the ones combining the three within one plan or flow. 

And before you send those emails to recipients, don’t forget to test them with a dedicated tool such as Mailtrap Email Testing. With its help, you can easily validate HTML/CSS, check the spam score, or test the email-sending functionality of your app.  

Once the tests are completed, pair it with Mailtrap Email Sending to test, send, and control your infrastructure, all in one place.