AIMultiple ResearchAIMultiple Research

Top 15 Transactional Email Services in 2024

Updated on May 15
10 min read
Written by
Cem Dilmegani
Cem Dilmegani
Cem Dilmegani

Cem is the principal analyst at AIMultiple since 2017. AIMultiple informs hundreds of thousands of businesses (as per Similarweb) including 60% of Fortune 500 every month.

Cem's work focuses on how enterprises can leverage new technologies in AI, automation, cybersecurity(including network security, application security), data collection including web data collection and process intelligence.

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Researched by
Sıla Ermut
Sıla Ermut
Sıla Ermut
Sıla Ermut is an industry analyst at AIMultiple focused on email marketing and sales videos. She previously worked as a recruiter in project management and consulting firms. Sıla holds a Master of Science degree in Social Psychology and a Bachelor of Arts degree in International Relations.
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Transactional emails are automated emails that are sent to an individual recipient following a specific action or trigger. The interest in these emails have been growing (See Google Trends graph) and there many transactional email providers with various features and pricing options to choose from.

This guide focuses on the top 15 transactional email providers while comparing their pricing options, key features, advantages and shortcomings to give a comprehensive analysis about the market.

Top 15 transactional email services

VendorNumber of reviewsAverage ratingFree planStarting price
Constant Contact8,4414.1$12/month
Brevo2,5174.5300 emails/day$15/month
SendPulse1,1974.612,000 emails/month$7/month
Moosend7554.71,000 subscribers, unlimited emails$9/month
Mailjet5864.26,000 emails/month, 200 emails per day$15/month
SMTP2GO4414.81,000 emails/month$10/month
Mailchimp Transactional Email4404.4500 emails/month$10/block for +161 blocks with +4M emails per month
Twilio SendGrid Email API3294.0100 emails/day$20/month for developers - $15/month for marketers
Mailgun1754.45,000 emails/month$35/month
Amazon Simple Email Service1654.33,000 emails/month for the first 12 months$0.10 per 1,000 email + additional chargers
UniOne434.8$6/month for 10,000 emails

Sorting in the above table: Sponsors are listed at the top with their links. The rest are sorted based on the number of B2B user reviews from G2 and Capterra.

Pricing information is gathered from the vendor websites. For a more detailed analysis, check out transactional email pricing and free transactional email tools.

Vendor selection criteria

We included vendors with:

  • at least 20 reviews from B2B review platforms to present public and verifiable data on the transactional email providers,
  • more than 20 employees as stated by LinkedIn,
  • providing core features such as sending trigger-based personalized emails, API integration, SMTP relay services, and dedicated IP addresses.

Differentiating features of transactional email services

VendorAutorespondersContact DatabaseList ManagementTemplate Management
Constant Contact
Mailchimp Transactional Email
Twilio SendGrid Email API
Amazon Simple Email Service

Detailed evaluation of each vendor dashboard overview

Figure 1: dashboard overview.1 is a transactional email and SMTP relay service mainly focusing on financial, eCommerce, tech start-ups, publishers, media and travel industries.

Reputation Defender: With its add-on Reputation Defender feature, SMTP supports domain and IP reputation by constantly monitoring email lists to boost delivery rates.

SMTP integrations: SMTP enables integration with Google Workspace tools including Google Sheets, Gmail, Google Calendar, Google Forms, Google Docs and lead form extensions as well as Slack, Airtable, Trello, Shopify, and WordPress for managing the automated processes.


Highly dependable: Users state that the solution’s security capabilities are the most helpful when compared to its competitors. See Figure 2.

SMTP user review on security capabilities

Figure 2: SMTP user review on G2.2

Delivery rates: Users praise SMTP email API for its higher delivery rates. See Figure 3.

SMTP user review on high deliverability

Figure 3: SMTP user review on G2.3

Integration capacities: Users find SMTP’s various integration options valuable and easy to use.4


Pricing: The lack of a free plan option is considered to be a disadvantage for SMTP. See Figure 4.

Users also state that pricing is higher for businesses that are not dealing with high volumes of emails.5

SMTP user review on pricing

Figure 4: SMTP user review on Capterra.6


Brevo campaign content creation example.

Figure 5: Brevo campaign content creation example.7

Brevo allows its users to manage their transactional emails, marketing campaigns, and customer interactions under one platform. Key features include:

Drag and drop editor: Brevo enables its user to design unique emails for increased personalization.


UI and customer support: Users state that Brevo’s user interface is highly intuitive and customer service is helpful with quick solutions. See Figure 6.

Brevo user review on UI and customer support

Figure 6: Brevo user review on Capterra.8

Automation: Users praise Brevo for its advanced automated email features such as sending welcome sequences and abandoned cart reminders.9


Limited options: Some users suggest Brevo to add more options for design templates10 and for marketing campaigns such as a throttling option.11


Sendpulse event creation overview.

Figure 7: SendPulse event creation overview.12

SendPulse is a multichannel platform designed for creating email campaigns, sending transactional emails and web push notifications. 


Live chat feature: Users find SendPulse’s live chat support service useful for addressing and managing issues quickly.13

Personalization: Users praise SendPulse for its advanced SMS, email, and push notifications personalization capabilities and they recommend the solution for businesses that prioritize higher personalization.14


Fraud protocol: Users suggest more advanced fraud detection services to manage security issues such as scamming and bounced emails. See Figure 8.

SendPulse user review on fraud protocol

Figure 8: SendPulse user review on Capterra.15

Integration: SendPulse’s limited integration capacities with other tools is considered to be a disadvantage.16


Moosend transactional email configuration

Figure 9: Moosend transactional email configuration.17

Moosend is an email marketing platform supporting businesses to automate outgoing emails, manage their email campaigns and subscriber lists.


Market fit: Moosend is found to be more useful for small to mid-level businesses. See Figure 10.

Moosend user review on its market fit

Figure 10: Moosend user review on Capterra.18

Deliverability capacities and customer service: Users state that Moosend’s high deliverability and supportive customer services are the most appreciated qualities.19


In the free version, Moosend does not provide SMTP integration and transactional email services.


SMTP2GO email testing feature overview

Figure 11: SMTP2GO email testing feature overview.20

SMTP2GO was founded in 2006 in New Zealand and supports its customers on their complex transactional email processes. 


Deliverability: Users state that SMTP2GO’s email and voicemail to email functions enable high deliverability when compared to its alternatives.21

Simplicity for non-technical users: SMTP2GO’s domain validation and user creation features are easy to use and do not require advanced technical knowledge. See Figure 12.

Reporting: Users praise SMTP2GO for its real-time reporting system that enables actionable insights on bouncing or spam emails. See Figure 12.

Figure 12: SMTP2GO user review on Capterra.22


API configuration: Improvements on the API integration is advised since it can be complicated for some users.23

Mailchimp Transactional Email

Mailchimp Transactional Email, formerly known as Mandrill, specializes in AI marketing tools and marketing automation such as customer journey building, webhooks and transactional emails.

Mailchimp provides various content creation capabilities with its content optimizer, creative assistant and subject lines helper for generating engaging email marketing content.


Email customization: Users praise Mailchimp’s customization options to create more intuitive email designs.24

Users state that Mailchimp is best suited for businesses without a CRM or email marketing expert in their marketing teams. See Figure 13.

Figure 13: Mailchimp user review on Capterra.25


Automated emails: Some users state that Mailchimp can be slower than its competitors while sending automated emails.26

Complex UI design: Mailchimp’s user interface can be considered as hard to understand for some users.27

Twilio SendGrid Email API

Figure 14: SendGrid transactional email templates.28

SendGrid Email API by Twilio is a cloud-based email delivery platform with marketing and transactional email capabilities.

SendGrid provides a multichannel communication with email, SMS, voice, or video services to support engagement with its users.


API integration: Users find SendGrid’s API integrations easy to use and helpful in generating higher interaction rates. See Figure 15.

SendGrid user review on API integration

Figure 15: SendGrid review on Capterra.29

Email templates: Users praise SendGrid for its useful features and various template options when compared to its alternatives.30


Customer support: Users report that SendGrid customer services are not as responsive as its competitors.31

Shared IP: SendGrid offers a dedicated IP address service only for Pro and higher plans and some users with lower plans experience deliverability and spamming issues. See Figure 16. 

SendGrid user review on shared IP problems

Figure 16: SendGrid user review on Capterra.32


Mailgun email reporting feature.

Figure 17: Mailgun email reporting feature.33

Mailgun by Sinch enables businesses to send, optimize and validate their email messages with SMTP relay and RESTful API integration services.


Reliability and integration: Users find Mailgun’s marketing email services reliable with minimum downtime. Additionally, users stated that the solution’s integration capacities for sending automated transactional messages are useful. See Figure 18.

Mailgun user review on Reliability and integration

Figure 18: Mailgun user review on Capterra.34


Spam detection: Users suggest improvements on Mailgun’s spam detection services.35

Search feature: Some users advice on adding a log search function by email content.36

Amazon Simple Email Service

As a part of Amazon Web Services (AWS) Business Applications, Amazon SES enables its users to test different scenarios such as managing bounces or complaints with its mailbox simulator.


Pricing: Users recommend Amazon SES for its cost-effective price per email pricing model.37


Customer support: Amazon SES support system is not efficient enough to manage deliverability issues on time. See Figure 19.

Amazon SES user review on customer support

Figure 19: Amazon SES user review on Capterra.38


Mailmodo campaign creation dashboard.

Figure 20: Mailmodo campaign creation dashboard.39

Mailmodo enables its users to integrate widgets from Zoom, Calendly, and Shopify for creating more interactive transactional email messages.


Features: Users praise Mailmodo for its easy to use transactional email features such as webhook and campaign triggers.40


Email templates: Some users state that template creation and customization processes are difficult.41

Reporting: Users find Mailmodo’s limited reporting capabilities as a disadvantage when compared to other solutions.42


SocketLabs sender reputation score dashboard.

Figure 21: SocketLabs sender reputation score dashboard.43

SocketLabs provides both cloud and on-premises servers to assist businesses’ transactional email processes.


Authentication: Users praise SocketLabs for its simplicity while setting up authentication features including DMARC (Domain-based Message Authentication, Reporting and Conformance) and DKIM (DomainKeys Identified Mail).44


Limited control on logging and monitoring options can be considered as a disadvantage of SocketLabs.45


UniOne allows specialized offers for startups and enterprises to support their scalable email management needs.


Users find UniOne’s real-time tracking and delivery status updates as an advantage. See Figure 22.

Figure 22: UniOne user review on Capterra.46


Some users advise UniOne on increasing the duration of data storage.47

What is a transactional email?

Transactional email services, also known as transactional email software, transactional email platform or transactional email tools, enable integration with SMTP email servers to deliver emails as a response to an user action on an application or a website. 

Most common examples of transactional email messages are order confirmations, shipping notices, account updates, password reset emails, and payment receipts.

Transactional email services core features

  • Trigger-based and automated messages that are personalized for each user,
  • API integration capabilities,
  • SMTP relay services to support successful delivery of emails among email systems,
  • IP warm-up and dedicated IP address services to ensure increased reputation while minimizing IP related security risks,
  • Authentication with DKIM (DomainKeys Identified Mail) and SPF (Sender Policy Framework) for secure email transmission,
  • Detailed reporting on email performance and analytics to track click-through and delivery rates, inbox placement, error and spam issues.

Differentiating features of transactional email services

Some transactional email services also enable more features that would differentiate them from their competitors. Some of these features include:

  • Autoresponders allow users to set up automated replies triggered by specific actions such as signing up for a newsletter or making a purchase. 
  • Contact database stores and manages information about each contact, such as email addresses, preferences, and interaction history. It enables personalized and targeted email campaigns based on the collected data.
  • List management feature allows users to segment and organize email lists based on various criteria like demographics, behavior, or subscription status.
  • Template management feature enables users to create, save, and edit email templates that can be reused for different campaigns. 

Check out email server software to learn more about transactional email and email servers.

How do transactional emails work?

The process of sending transactional emails includes:

Triggering an event: The user or the system triggers specific action or event. These triggers can be order placement, account sign-up, or password reset link request.

Generating the email: After the user triggers an event, a personalized email that is focusing on a specific situation or the relevant information retrieved from the user is generated by the system.

This process usually includes choosing the most relevant transactional email templates and using them to create email content about the user’s name, transaction details, and any relevant instructions.

Send emails: Through a SMTP server, transactional messages are then sent to the recipient’s email address.

Delivery and Tracking: After the sending process, the email delivery process is usually tracked by the transactional email provider. This process includes monitoring for bounces, opens, and clicks to ensure delivery of successful transactional emails to the recipient.

How do different industries use transactional email software?

Transactional emails are used by a wide range of businesses and organizations across various industries including e-commerce platforms, financial services, social media platforms, SaaS (Software as a Service) companies, and healthcare providers. Check out the primary users and how they use transactional emails for their businesses:

E-commerce platforms and financial services

  • Order confirmations: A transactional email is sent to confirm the order following a purchase. The email usually provides details about the product, the charged amount of the purchase, and the expected delivery date.
  • Shipping notifications: The users receive an email update with tracking information after the shipment. This informs customers about the status of their deliveries and minimizes the need for customer service inquiries about shipped order statuses.
  • Payment receipts and invoices: Transactional emails are used to send payment receipts or invoices.
  • Cart abandonment reminders: E-commerce platforms usually send emails to users who have added items to their shopping cart but have not completed the purchase. These reminder emails can include details of the items in the cart or a call to action to complete the purchase.
  • Product recommendations and re-stock notifications: Customers can receive personalized product recommendations based on previous purchases or browsing history. Additionally, an automated email can notify customers for recently available out-of-stock items.

SaaS companies and social media platforms

  • Account creation and verification emails: When a new user signs up on a platform, transactional emails are used for account verification. This typically involves sending a link or a code that the users must click to verify their email address and activate their account.
  • Password reset: When the users trigger a password reset request, they receive an email with a link to securely reset their password.
  • Usage alerts: Sending transactional emails can also inform and alert users on their subscription usage and can also provide an unsubscribe link.

Healthcare providers

Transactional emails can be delivered for appointment confirmations and reminders, as well as patient portal notifications.

Transactional emails vs. marketing emails

Transactional emails are triggered by user actions and provide specific information related to those actions. They are personalized and directly tied to the user’s recent activity.

In contrast, email marketing messages are part of a broader strategy to promote products, services, or brands. They aim to engage, inform, or persuade customers, often through newsletters or promotional offers. While they may target specific customer segments, they are not tied to individual user actions.

The primary goal of transactional emails is to provide necessary information, while marketing emails aim to increase sales or customer engagement by encouraging specific actions.

Learn more on transactional email vs marketing email.

Transparency statement

AIMultiple collaborates with various technology vendors including

Cem Dilmegani
Principal Analyst

Cem is the principal analyst at AIMultiple since 2017. AIMultiple informs hundreds of thousands of businesses (as per Similarweb) including 60% of Fortune 500 every month.

Cem's work focuses on how enterprises can leverage new technologies in AI, automation, cybersecurity(including network security, application security), data collection including web data collection and process intelligence.

Cem's work has been cited by leading global publications including Business Insider, Forbes, Washington Post, global firms like Deloitte, HPE, NGOs like World Economic Forum and supranational organizations like European Commission. You can see more reputable companies and media that referenced AIMultiple.

Cem's hands-on enterprise software experience contributes to the insights that he generates. He oversees AIMultiple benchmarks in dynamic application security testing (DAST), data loss prevention (DLP), email marketing and web data collection. Other AIMultiple industry analysts and tech team support Cem in designing, running and evaluating benchmarks.

Throughout his career, Cem served as a tech consultant, tech buyer and tech entrepreneur. He advised enterprises on their technology decisions at McKinsey & Company and Altman Solon for more than a decade. He also published a McKinsey report on digitalization.

He led technology strategy and procurement of a telco while reporting to the CEO. He has also led commercial growth of deep tech company Hypatos that reached a 7 digit annual recurring revenue and a 9 digit valuation from 0 within 2 years. Cem's work in Hypatos was covered by leading technology publications like TechCrunch and Business Insider.

Cem regularly speaks at international technology conferences. He graduated from Bogazici University as a computer engineer and holds an MBA from Columbia Business School.

Sources: Traffic Analytics, Ranking & Audience, Similarweb.
Why Microsoft, IBM, and Google Are Ramping up Efforts on AI Ethics, Business Insider.
Microsoft invests $1 billion in OpenAI to pursue artificial intelligence that’s smarter than we are, Washington Post.
Data management barriers to AI success, Deloitte.
Empowering AI Leadership: AI C-Suite Toolkit, World Economic Forum.
Science, Research and Innovation Performance of the EU, European Commission.
Public-sector digitization: The trillion-dollar challenge, McKinsey & Company.
Hypatos gets $11.8M for a deep learning approach to document processing, TechCrunch.
We got an exclusive look at the pitch deck AI startup Hypatos used to raise $11 million, Business Insider.

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