An SMTP server (Simple Mail Transfer Protocol server) is a computer or application responsible for sending, receiving, and relaying outgoing emails between senders and receivers. Here’s a breakdown of how it works:
- Sending Emails: When you send an email, your email client (like Gmail, Outlook, etc.) connects to an SMTP server. The server processes the email and determines the recipient’s email server.
- Relaying Emails: If the recipient’s email server is different from the sender’s, the SMTP server relays the email to the appropriate server using the Domain Name System (DNS) to find the recipient’s IP address.
- Receiving Emails: The recipient’s email server then receives the email and stores it until the recipient retrieves it using a different protocol, such as IMAP or POP3.
SMTP servers are crucial for ensuring that emails are delivered accurately and efficiently across the internet. Without them, email communication wouldn’t be possible.
Here is our list of the best SMTP servers:
- MailerSend EDITOR’S CHOICE This cloud-based system manages transactional emails through an API so it enables developers to integrate email functions into new applications. The service enables automated emails to be sent out in scenarios such as autoresponse or brochure delivery.
- SMTP2Go A reliable SMTP service with excellent deliverability, real-time analytics, easy integration, and an intuitive interface that is ideal for non-technical users.
- SendPulse A versatile, budget-friendly platform combining email marketing, SMS, and web push notifications with schedules and event-triggered automation.
- Brevo (formerly SendinBlue) Offers both email marketing and transactional email services. Affordable with strong automation and segmentation features.
- Mailjet A collaborative email marketing and transactional platform that supports real-time collaboration, making it great for teams.
- AhaSend This simple and affordable up-and-coming email platform has promising features for both marketing and transactional emails.
- Mailtrap Primarily a testing tool for developers, this tool allows safe email testing in staging environments, preventing delivery to real users.
The Best SMTP Servers
There are many SMTP servers available on the market at the moment and it will take you a long time to sift through them all in order to create a shortlist to consider. This is why we created this guide, so you can fast-forward to just the best candidates.
Our methodology for selecting an SMTP server
We reviewed the market for SMTP servers and selected tools based on the following criteria:
- A high deliverability rate so your emails reach the intended recipients without being marked as spam.
- Strong encryption and authentication protocols to protect sensitive data and prevent unauthorized access.
- The server should be able to handle your current email volume and scale as your needs grow.
- A strong uptime record and reliable performance to ensure your emails are sent and received without delays.
- Good customer support and comprehensive documentation that will help you master the system quickly.
- A free trial or a test account to enable the system to be evaluated before paying.
- Value for money from a package that has an appropriate price given the functions on offer.
All the systems that we found are cloud-based services.
1. MailerSend
MailerSend is a transactional email service tailored to developers and businesses requiring reliable, secure, and efficient email infrastructure. Known for its simplicity and easy-to-access API, it allows integration into existing platforms. MailerSend focuses on delivering high-volume emails such as order confirmations, password resets, and notifications, all while providing extensive analytics and excellent deliverability.
Key Features:
- Processes transactional emails: Optimized for sending high-volume emails like invoices, receipts, and password resets.
- Drag-and-drop editor: Allows easy email template creation without coding skills.
- API and SMTP integration: Lets you integrate email sending into your own applications.
- Analytics: Real-time tracking of open rates, click-through rates, and bounce data.
- Team collaboration: Multiple user roles, ideal for teams managing email workflows.
Why Do We Recommend It?
MailerSend offers a great balance between ease of use and developer-focused features. Its fast and secure email infrastructure, combined with detailed analytics and a responsive API, makes it an excellent choice for businesses that need reliable transactional email services.
I found that Security features in the MailerSend package include a built-in email verification system to maintain a clean mailing list. Security measures for outgoing emails include Domain Key Identified Mail (DKIM) that blocks spam and impersonation attempts, Sender Policy Framework (SPF) for authentication, and Transport Layer Security (TLS) for connection encryption.
Who Is It Recommended For?
MailerSend is recommended for businesses, SaaS platforms, and eCommerce sites that rely heavily on transactional emails. Its API and SMTP integration make it ideal for developers, while the user-friendly interface is suitable for marketers who need to manage templates and monitor email performance.
Pros:
- Highly customizable email templates: Custom HTML templates for businesses that want complete design control.
- Scalability: MailerSend is capable of scaling from small projects to high-volume email needs.
- Responsive customer support: The support team is known for being prompt, knowledgeable, and helpful.
- Transparent pricing: No hidden fees or complicated pricing models.
- Fast email delivery: Lightning-fast email delivery times, ensuring transactional emails reach users promptly.
Cons:
- Limited marketing automation features: Might not be ideal for large-scale email marketing campaigns.
MailerSend is cloud-based, making it accessible across devices. It offers flexible pricing based on the number of emails sent, with a pay-as-you-go model for businesses that scale. Plans start with a free tier of 3,000 emails per month, allowing users to test the platform without upfront costs. Paid tiers include premium support and advanced features like priority delivery and dedicated IPs. Start by accessing a free test account.
EDITOR'S CHOICE
MailerSend is our top pick for an SMTP server because it is designed to facilitate reliable and secure email delivery. It offers a range of features that cater to both small businesses and large enterprises. One of the key strengths of MailerSend is its high deliverability rate, ensuring that emails reach their intended recipients without being marked as spam. The platform supports essential security protocols such as SPF, DKIM, and DMARC, which help protect your sending domain from unauthorized use and maintain a good sender reputation. The package also provides a user-friendly interface and comprehensive documentation, making it easy to set up and manage your SMTP settings. The service includes detailed analytics and reporting tools, allowing users to monitor email performance and troubleshoot issues effectively. Scalability is another advantage of MailerSend, with various plans available to accommodate different email volumes. This flexibility ensures that the service can grow with your business needs. Additionally, MailerSend offers a free plan, which is beneficial for startups and small businesses looking to manage costs while still accessing essential features.
OS: Cloud based
2. SMTP2Go
SMTP2Go is a cloud-based email delivery service designed to ensure reliable email delivery and prevent messages from landing in spam folders. It’s widely used for both transactional and marketing emails, offering exceptional uptime and fast delivery speeds. With its ease of use, strong customer support, and real-time tracking, SMTP2Go is a great choice for businesses of all sizes looking for dependable email delivery.
Key Features:
- SMTP relay service: Ensures secure and reliable email sending across multiple platforms.
- Real-time analytics: Track open rates, click-throughs, and bounce rates with detailed reporting.
- Dedicated IP addresses: Improve email deliverability and sender reputation with optional dedicated IPs.
- Email testing: Preview how emails will appear across various devices and email clients.
Why Do We Recommend It?
SMTP2Go is ideal for businesses that need a reliable SMTP service with excellent deliverability rates. I noted that the platform’s real-time reporting, security features, and global infrastructure provide assurance that emails are sent quickly and securely, making it a standout solution for transactional and marketing purposes.
Who Is It Recommended For?
SMTP2Go is perfect for businesses of any size that require high email deliverability, including those sending marketing or transactional emails. It’s especially suited for companies that want a hassle-free SMTP relay setup and developers who require email integration with minimal configuration.
Pros:
- Integrations: Works seamlessly with CRMs, eCommerce platforms, and web-based applications.
- Excellent email deliverability: Consistently high delivery rates, ensuring emails land in inboxes rather than spam folders.
- Easy setup and configuration: Setting up the service is straightforward, even for non-technical users.
- Reliable global infrastructure: Global servers provide fast delivery speeds and reduce latency for international recipients.
Cons:
- Limited email template design capabilities: More focused on transactional than marketing emails.
SMTP2Go is a cloud-based platform, accessible from any device with internet connectivity. It offers a Free edition, which is limited to processing 1,000 emails per month. Paid plans start affordably, with pricing based on the number of emails sent per month. The service also offers flexible, pay-as-you-go options for businesses with fluctuating email needs.
3. SendPulse
SendPulse is a versatile, multichannel marketing platform offering email, SMS, and web push notifications. Known for its user-friendly interface and wide range of automation features, SendPulse caters to businesses looking to create cross-channel campaigns without technical complexity. It provides a drag-and-drop email builder, pre-built automation flows, and a wide range of integrations.
Key Features:
- Email, SMS, and push notifications: Multi-channel marketing to reach audiences through various touchpoints.
- Drag-and-drop email builder: Create visually appealing emails without needing design or coding skills.
- Automation workflows: Set up automated email sequences based on customer behavior.
Why Do We Recommend It?
SendPulse stands out for its multichannel marketing capabilities, making it a powerful tool for businesses that want to combine email with SMS and push notifications. I learned that its wide range of features, intuitive interface, and marketing automation make it an excellent all-in-one marketing solution.
Who Is It Recommended For?
SendPulse is ideal for small to medium-sized businesses and marketers looking to build multichannel campaigns. It’s particularly suited for companies seeking an affordable solution to automate email marketing while also using SMS and push notifications for higher engagement and conversion rates.
Pros:
- A/B testing: Optimize email campaigns by testing subject lines, content, and sending times.
- AI-powered personalization: Use machine learning to personalize emails based on user behavior.
- Landing page builder: Build and host landing pages directly on the platform to complement campaigns.
Cons:
- Limited design flexibility: Other tools provide more email template customization options.
SendPulse is a cloud-based platform, allowing users to access it from any internet-connected device. It offers a free plan that allows up to 500 subscribers and 15,000 emails per month, making it a great option for smaller businesses to try out the platform. Paid plans start affordably and scale based on the number of subscribers, with added benefits like advanced segmentation and priority support at higher tiers.
4. Brevo (formerly SendinBlue)
Brevo is a powerful email marketing and transactional email service that combines email, SMS, and CRM tools into one platform. It provides an affordable range of features like marketing automation, segmentation, and transactional email management, making it popular among small and medium-sized businesses. Its intuitive interface and rich feature set allow users to easily create, send, and monitor marketing campaigns.
Key Features:
- Email and SMS marketing: Integrated email and SMS campaigns for multichannel communication.
- Marketing automation: Automate email sequences based on user behavior and preferences.
- CRM integration: Built-in CRM helps track and manage customer interactions.
Why Do We Recommend It?
Brevo combines powerful marketing tools with affordability, making it a great choice for growing businesses. I discovered that its automation features and built-in CRM provide an all-in-one solution for managing customer engagement, while its scalable pricing allows companies to grow without excessive costs.
Who Is It Recommended For?
Brevo is ideal for small to medium-sized businesses looking for a cost-effective platform to manage both marketing and transactional emails. It’s particularly well-suited for companies that want to automate email marketing while integrating SMS and customer management without needing multiple platforms. The free plan will appeal to very small businesses.
Pros:
- Segmentation: Create tailored campaigns by segmenting your audience based on demographics or actions.
- Transactional email: Reliable SMTP for transactional emails like order confirmations and password resets.
- A/B testing: Test different elements of your emails to find what performs best.
Cons:
- Uneven customer support: Customer support is slower on lower-tier plans.
Brevo is fully cloud-based and accessible from any web-enabled device. It offers a free plan that includes unlimited contacts and up to 300 emails per day. Paid plans start at a budget-friendly rate, scaling based on the number of emails sent per month and additional features like advanced reporting, marketing automation, and phone support.
5. Mailjet
Mailjet is a versatile email marketing and transactional email service known for its real-time collaboration and strong email deliverability. The platform caters to both marketers and developers, allowing teams to collaborate on email campaigns, manage transactional emails, and track performance with in-depth analytics.
Key Features:
- Email marketing: Create and send marketing emails with easy-to-use templates.
- Transactional emails: Reliable SMTP relay for sending invoices, order confirmations, and other transactional messages.
- Real-time collaboration: Multiple team members can work on email templates and campaigns simultaneously.
Why Do We Recommend It?
Mailjet stands out for its unique real-time collaboration feature, which makes it an excellent choice for teams working together on email campaigns. I observed that combined with strong deliverability and ease of integration, it’s a reliable platform for both marketing and transactional emails.
Who Is It Recommended For?
Mailjet is recommended for medium-sized businesses, teams, and developers looking for an all-in-one solution for marketing and transactional emails. It’s particularly suited for companies that need seamless team collaboration on email campaigns or developers who want API integration for transactional emails.
Pros:
- Advanced analytics: Track opens, clicks, bounce rates, and engagement metrics in real-time.
- A/B testing: Optimize campaigns by testing different subject lines, content, and sending times.
- API and SMTP relay: Developer-friendly API and SMTP integration for seamless sending.
Cons:
- Limited automation features: Lacks the depth of automation workflows found in other platforms.
Mailjet is cloud-based and accessible from any device with internet access. It offers a free plan that includes 6,000 emails per month, with a limit of 200 emails per day. Paid plans start affordably and scale based on the number of emails sent and features needed, such as advanced analytics, A/B testing, and priority customer support. This flexibility makes Mailjet a good fit for businesses of all sizes, especially those with growing email needs.
6. AhaSend
AhaSend is an emerging email marketing and transactional email platform designed to help businesses easily create and manage email campaigns. Its straightforward interface and practical tools make it a suitable option for small to medium-sized businesses. AhaSend supports both marketing and transactional emails, allowing users to send bulk emails, set up automation flows, and track performance metrics, all while remaining budget-friendly.
Key Features:
- Email marketing: Create and send newsletters, promotional emails, and marketing campaigns.
- Transactional emails: SMTP support for sending order confirmations, receipts, and other transactional emails.
- Drag-and-drop editor: Build emails with a simple drag-and-drop interface for ease of use.
Why Do We Recommend It?
AhaSend is an easy-to-use platform that offers a solid range of email marketing tools for growing businesses. I noticed that its balance of simplicity and functionality, combined with cost-effectiveness, makes it a great option for companies that want reliable email capabilities without breaking the bank.
Who Is It Recommended For?
AhaSend is ideal for small and medium-sized businesses, entrepreneurs, and marketers looking for an affordable and straightforward platform to manage email campaigns and transactional emails. It’s especially well-suited for those who want essential features without the complexity of more advanced platforms.
Pros:
- Automation workflows: Set up basic email sequences triggered by customer actions.
- Analytics: Track email performance, including opens, clicks, and bounce rates.
- Segmentation: Target specific audience segments for more personalized campaigns.
Cons:
- Limited integrations with third-party apps: Also has a smaller feature set compared to well-established competitors.
AhaSend is a cloud-based platform, accessible from any device with internet access. It offers a Free edition, which also works as a free trial opportunity for larger businesses. The pricing is based on the number of emails sent per month, with higher tiers offering advanced analytics, premium support, and additional email volume.
7. Mailtrap
Mailtrap is a specialized email testing platform designed for developers to safely test, preview, and debug emails in a staging environment before sending them to real recipients. It stimulates the email-sending process without delivering to actual inboxes, ensuring that developers can troubleshoot potential issues like broken links, incorrect formatting, or deliverability problems.
Key Features:
- Email testing: Safely test email functionality without sending real emails to users.
- Shared inboxes: Centralized testing inboxes for teams to collaborate and review emails.
- Spam score analysis: Helps identify whether an email is likely to be flagged as spam.
Why Do We Recommend It?
Mailtrap excels at providing a safe environment for email testing and debugging, allowing developers to catch errors and optimize emails before going live. I found that its ability to simulate the entire email lifecycle makes it indispensable for developers working with transactional emails or building email systems.
Who Is It Recommended For?
Mailtrap is ideal for developers, QA teams, and software companies who need a secure environment to test email functionality. It’s especially useful for teams working on transactional email systems or web apps that send automated emails, helping ensure everything works smoothly before going live.
Pros:
- Email previews: Preview how emails render across different devices and clients.
- Email forwarding: Forward test emails to your actual inbox for further inspection.
- API integration: Connect Mailtrap with your app or email system for automated testing.
Cons:
- Not suitable for production email sending: Purely for testing purposes.
Mailtrap is a cloud-based platform accessible via a web browser or API. It offers a free plan with limited inboxes and emails for basic testing, making it easy for developers to try before committing. Paid plans are based on the number of inboxes, emails, and additional features like spam score checks and forwarding.
