6 Best SMTP Servers for 2025

Sending emails is an integral part of communication for businesses and individuals alike. Whether you're running a small business, managing marketing campaigns, or simply need a reliable method for sending bulk emails, having the right SMTP (Simple Mail Transfer Protocol) server is essential.

An SMTP server acts as the backbone for email delivery. It is the underlying system that delivers your messages to their intended recipients without delays or errors. This article will guide you through the process of choosing the right SMTP server that meets your needs. You'll explore the 6 best SMTP servers, highlighting their features, and benefits, in order to help you make an informed decision.

Here is the list of the best SMTP servers:

SendGrid A scalable solution that offers both transactional and marketing email capabilities.
SMTP.com Provides robust infrastructure for transactional and marketing emails with excellent analytics.
Brevo (formerly Sendinblue) Known for its powerful platform that combines email marketing services with reliable SMTP relay.
Mailgun Great for developers due to its powerful APIs for sending, receiving, and tracking emails effortlessly.
Mailjet Offers a user-friendly interface and real-time analytics, suitable for both developers and marketers.
Postmark Specializes in transactional emails, with a focus on speed and reliability.

The Best SMTP Servers

Our methodology for selecting these SMTP servers

In selecting our top SMTP servers, a combination of factors were considered to provide a well-rounded list:

Server Performance and Reliability: We assessed each server’s processing speeds and reliability in email delivery, and prioritized servers with higher performance and minimal downtime.
Security Features: We selected providers offering robust security measures such as encryption , authentication protocols, and features like IP blocking or rate-limiting to defend against spam and malicious activities.
Email Deliverability and Reputation: We favored providers with strong IP reputation management, proper DNS configurations, and consistent monitoring of blacklisting.
Support and Customer Service: We examined the quality of customer support, considering factors such as 24/7 availability, various communication channels (live chat, phone, email), and helpful resources like knowledge bases and tutorials.
Pricing and Plans: We looked for providers offering scalable solutions that can grow with your needs, without hidden fees or email volume restrictions.

1. SMTP.com

SMTP.com is a cloud SMTP service provider founded in 1998 that specializes in handling outgoing emails for high-volume senders. It operates its own redundant data center in the US, and offers a range of services including tracking and reporting, reputation management, statistical analysis, and expert support. The service also provides tools for verifying a domain's DKIM records in DNS and checking forward-confirmed reverse DNS. SMTP.com requires that emails be generated locally from an internally maintained email list.

Key Features:

Email Relay API: SMTP.com offers an easy-to-use API for email relay. This enables businesses to send large volumes of emails through a reliable SMTP server.
Scalable Infrastructure: SMTP.com can handle changing email delivery demands, from small volumes to billions of emails per month, without compromising performance.
High Deliverability Rates: SMTP.com’s established reputation ensures that emails are delivered reliably, with high success rates.
Transactional Email: SMTP.com specializes in sending high-volume transactional emails such as order confirmations, password resets, and notifications.
Managed Delivery: SMTP.com ensures reliable email delivery with its scalable infrastructure that adapts to fast delivery speed requirements.
Turnkey Migration: SMTP.com offers migration assistance to help businesses transition smoothly from other SMTP service providers.
Custom API Integrations: SMTP.com offers expert help with custom API integrations for smooth email delivery setups tailored to business needs.

Why Do We Recommend It?

With over two decades of experience, SMTP.com offers unmatched deliverability rates and robust infrastructure that ensures emails reach their intended recipients efficiently. Its scalable platform can handle billions of emails per month while maintaining speed and performance.

Who Is It Recommended For?

Consider SMTP.com if you run a business that requires reliable, high-volume email delivery with a strong emphasis on deliverability and scalability. It’s definitely a great tool for large-scale enterprises, e-commerce platforms, SaaS providers, and businesses that rely on transactional emails like order confirmations, password resets, or notifications.

SMTP.com is also a strong fit for organizations that are transitioning from other email service providers, as it offers turnkey migration services to make the process effortless.

Pros:

Expert Support: The support team is knowledgeable and offers specialized help for any email delivery issues or integration challenges.
Managed Onboarding: The onboarding process is straightforward and well-supported by a dedicated account management team, making it easier for businesses to get started.
SMTP for Developers: Designed with developers in mind, SMTP.com provides a robust and flexible SMTP service for integration with applications, websites, and systems.
SMTP for Marketers: The platform offers tools that help marketers send and manage email campaigns, track performance, and optimize for better results.

Cons:

Primarily Focused on High-Volume Senders: While the platform is excellent for large-scale email campaigns, it may not be the most cost-effective option for small businesses or low-volume senders.
Premium Pricing: SMTP.com is a premium service, which might not be the most cost-efficient option for businesses just starting with email marketing or transactional emails.

2. SendGrid

SendGrid is a cloud-based service founded in 2009 that provides email delivery and marketing solutions, widely recognized as one of the leading SMTP servers in the world. The service manages various types of emails, such as shipping notifications, sign-up confirmations, and newsletters.

Key Features:

Proven Deliverability: SendGrid is known for its high inbox placement rates, and has minimal risk of emails being caught in spam filters.
Scalability: With the ability to send billions of emails each month, SendGrid’s platform is built for businesses of all sizes, and supports high-volume campaigns without compromising on performance.
Expert Support: SendGrid offers expert email support, including strategic consulting, troubleshooting assistance, and deliverability optimization.
Flexible Email API: SendGrid’s powerful Email API provides seamless integration for developers, along with comprehensive documentation and an intuitive user interface.
Email Automation: SendGrid offers simple, intuitive tools for creating impactful email automations. This allows marketers to design high-conversion email flows quickly with minimal effort.

It also includes SMS, voice, and push notifications, while allowing companies to track email opens, unsubscribes, bounces, and spam reports. SendGrid is used by thousands of developers and marketers to ensure their email communications are delivered quickly and reliably.

Why Do We Recommend It?

SendGrid stands out for its proven deliverability, scalability, and advanced features. The platform also offers powerful email automation, a flexible API for easy integration, and expert support to optimize email marketing campaigns, which sets it apart from many competitors.

Who is It Recommended For?

SendGrid is ideal for digital marketing firms, e-commerce platforms, SaaS providers, and businesses with high email demands that require consistent, high-performance email delivery, especially those managing large email volumes.

Pros:

Reliability: SendGrid is known for robust uptime and minimal delivery delays.
Scalability: Its infrastructure can easily handle the email demands of both small businesses and large enterprises. This makes it an excellent choice for businesses anticipating growth.
Expert Assistance: SendGrid's team of experts offers support ranging from technical troubleshooting to strategic advice. This ensures the continued success of your business's email marketing efforts..
Comprehensive Analytics: The platform provides detailed metrics on email performance, such as open rates, clicks, geolocation, and device usage. This allows businesses to refine their strategies and improve engagement.

Cons:

Pricing: While SendGrid offers flexible pricing, it can be more expensive compared to other SMTP services, especially for smaller businesses or those with lower email volumes.
Learning Curve for New Users: While the platform offers an intuitive UI, new users may require some time to become familiar with the advanced features and configuration options available.

3. Brevo

Brevo is a prominent SMTP provider and SaaS platform designed to enhance relationship marketing. Since its founding in 2012, Brevo has gained recognition for its robust, cloud-based communication solutions, offering a comprehensive suite of marketing tools for businesses.

Key Features:

SMTP Email Delivery: Brevo offers reliable and secure SMTP email delivery for both transactional and marketing emails.
Marketing Automation: Brevo enables businesses to automate their marketing emails, such as welcome sequences, cart abandonment emails, and promotional campaigns.
Advanced Analytics and Reporting: Brevo provides comprehensive tracking and analytics, including open rates, click-through rates, bounces, unsubscribes, and more.
CRM Integration: Brevo integrates with customer relationship management (CRM) systems to streamline email marketing efforts. This ensures that emails are personalized and sent to the right contacts.
Customizable API Integrations: Brevo offers flexible API integrations that enable developers to connect its service to websites, applications, and systems for automated email delivery.
Excellent Customer Support: The platform offers comprehensive support, including live chat, email support, and detailed documentation

Why Do We Recommend It?

As an SMTP server, Brevo specializes in reliable, high-performance email delivery that empowers businesses to manage both transactional and marketing emails efficiently. Beyond email services, Brevo offers a variety of marketing and communication tools, such as marketing automation, CRM, landing page creation, and more.

Brevo offers a pay per usage pricing model, superb customer service in multiple languages and provides dedicated support for higher-tier plans, including a guaranteed one-hour response time for Enterprise users. It also ensures that even non-technical users can set up and manage email campaigns without hassle through its user-friendly interface, simple onboarding process, and drag-and-drop editors.

Who Is It Recommended For?

Brevo is an excellent choice for businesses looking for an easy-to-use and cost-effective email solution. With its intuitive design, comprehensive help resources, and great value, Brevo is a powerful tool for businesses looking to simplify their tech stack while accessing high-end digital solutions.

Pros:

CRM Integration: Brevo integrates with CRM systems to streamline email marketing efforts, and ensures that emails are personalized and sent to the right contacts.
High Deliverability: Brevo has a strong reputation for ensuring emails are delivered to the inbox, with features designed to enhance deliverability and avoid spam filters.
All-in-One Marketing Platform: With tools for email marketing, automation, CRM, landing pages, and more, Brevo is an all round platform for businesses looking to manage their entire marketing communication strategy.
Scalable and Flexible: Whether sending a few emails or millions, Brevo's infrastructure is designed to scale with the needs of businesses.
Multichannel Communication: Brevo provides communication solutions across various channels such as SMS, voice, and push notifications.

Cons:

Complexity for Beginners: New users or small businesses with limited technical expertise may find the variety of features and options overwhelming at first.
Pricing Structure: Brevo’s pricing may not be the most cost-effective option for very small businesses or those with low email volumes.

4. Mailgun

Since its founding in 2010, Mailgun has been a leader in providing reliable, API-based email services that are easy to integrate into apps and websites. With a focus on deliverability, Mailgun allows businesses to send and track transactional and marketing emails with ease.

Key Features:

Email API: Mailgun provides a powerful and easy-to-use API for seamless integration of email sending and receiving into applications, websites, and systems.
Transactional Emails: Mailgun is ideal for sending time-sensitive transactional emails such as order confirmations, password resets, and notification alerts.
Email Validation: The platform includes built-in email validation to help businesses maintain clean, valid email lists, reducing bounces and improving deliverability.
Send Time Optimization: Mailgun optimizes email delivery times based on customer behavior and engagement data. This ensures emails are sent at the optimal moment for higher engagement.
Email Analytics: Mailgun provides advanced email analytics, including open rates, click-through rates, bounce rates, and more.
Burst Sending: Mailgun supports burst sending, which allows businesses to send large volumes of emails quickly during peak times without compromising performance.

Mailgun is trusted by hundreds of thousands of companies and leading brands worldwide, sending hundreds of billions of emails every year. Whether you're a small startup or a large enterprise, Mailgun’s reliable infrastructure and expert guidance make it a top choice for modern email delivery solutions.

Why Do We Recommend It?

We recommend Mailgun because it is a powerful, all-in-one email delivery platform that combines ease of use with developer-friendly features. Its robust infrastructure helps businesses prevent fake signups, quickly remove invalid email addresses, and improve overall email deliverability, which in turn drives higher conversion rates. With world-class support, advanced APIs, and a data-driven approach,

Who Is It Recommended For?

Mailgun is particularly suited for tech-savvy teams, e-commerce platforms, SaaS providers, and startups looking to integrate transactional and marketing emails seamlessly. With its powerful APIs, focus on deliverability, and fraud prevention tools, Mailgun is ideal for those seeking efficient, data-driven email solutions that can scale as their business grows.

Pros:

Developer-Friendly: Mailgun’s API and easy integration make it a great choice for developers who need to integrate email capabilities into applications or websites quickly.
Reliable Deliverability: Mailgun helps businesses maximize engagement by making sure that emails are delivered to the inbox, not the spam folder.
Scalable: Mailgun offers a scalable infrastructure that can handle email volumes ranging from small businesses to large enterprises. This makes it suitable for a wide range of users.
Advanced Analytics: The platform helps businesses measure and improve the performance of their email campaigns through its in-depth tracking and analytics.

Cons:

Complexity for Non-Developers: While Mailgun is excellent for developers, it may be difficult for non-technical users to navigate, particularly when integrating the API or configuring advanced features.
Learning Curve: Mailgun’s extensive features and configuration options may require some time to fully understand, especially for those who are new to email services.

5. MailJet

Mailjet is a cloud-based SMTP server that is recognized for its ability to deliver both transactional and marketing emails efficiently. It was founded in 2010 in Paris, France. With a user-friendly interface and a strong set of features, Mailjet has become one of the top choices for businesses looking to manage their email communication at scale.

Key Features

AI Copy Generator: The AI-powered tool helps automate email content creation, improving both the efficiency and quality of emails while saving time for businesses.
Easy-to-Use Email Editor: Mailjet’s drag-and-drop email editor allows users of any skill level to design responsive emails and forms quickly.
Automation: Automate emails like welcome messages, onboarding emails, and date-based communications to save time and engage with subscribers at crucial moments in their journey.
A/B Testing: Run A/B tests on various elements such as subject lines, visuals, and sender names to optimize email performance and improve engagement rates.
Real-Time Analytics: Track email deliverability, customer engagement, and campaign performance in real-time.
Third-Party Integrations: Mailjet supports seamless integration with a variety of third-party tools, including CRM, CMS, and ecommerce platforms.

Why Do We Recommend It?

We recommend Mailjet as an SMTP server due to its high deliverability rates, scalability, and user-friendly interface, making it a solid choice for businesses of all sizes. It offers easy integration through a developer-friendly API and provides advanced features like real-time analytics, email personalization, and robust security options. These features make it an ideal solution for businesses that need reliable email sending and tracking capabilities, whether for marketing campaigns or transactional emails.

Who Is It Recommended For?

Mailjet is a great fit for those who require an easy-to-use SMTP platform with powerful capabilities but don’t want to manage the complexities of an in-house email infrastructure. Larger enterprises with high email volumes can also benefit from its scalability and enterprise-level features, ensuring a smooth experience as their needs grow.

Pros:

Excellent Deliverability: With built-in tools to help maintain a strong sending reputation and expert-approved deliverability features.
User-Friendly Interface: Mailjet’s drag-and-drop email editor makes it easy for beginners to design professional emails without any coding knowledge.
Collaboration Features: The platform supports real-time collaboration, allowing teams to work together on campaigns, with customizable permissions to protect brand consistency.
Competitive Plans: Mailjet offers competitive and transparent pricing with plans that cater to businesses of all sizes.

Cons:

Learning Curve for Advanced Features: While the basic email editor is easy to use, some of the more advanced features might require a learning curve for newcomers.
Pricing for Higher Volumes: For businesses with very high email volumes, the cost of scaling on Mailjet may become a concern.

5. Postmark

Postmark is recognized as one of the leading SMTP servers, primarily known for its high-speed, reliable delivery of transactional emails. Unlike other email delivery platforms, Postmark specializes in ensuring that critical communications such as password resets, account notifications, and user alerts reach their recipients' inboxes promptly and without delay.

Key Features:

SMTP Service: With its reliable SMTP service, Postmark ensures the fast delivery of transactional emails, including password resets, notifications, and user alerts.
Message Streams: Postmark allows businesses to separate different types of emails (e.g., transactional and promotional) into distinct message streams to ensure optimal deliverability and manageability.
Rebound: Postmark's rebound feature helps businesses manage and track bounced emails to ensure better list management and improved overall deliverability.
Email API: Postmark offers a powerful and easy-to-use API that allows businesses to seamlessly integrate email sending capabilities into their applications and systems.
Webhooks: Postmark provides webhooks for real-time notifications about email events, such as deliveries, bounces, and opens, so businesses can automate responses and monitor performance.
Analytics: Postmark offers detailed analytics and reporting tools that track email performance, including open rates, bounce rates, and delivery success.

With its robust API and seamless integration into various programming languages, Postmark is an ideal choice for developers and businesses who need a trustworthy SMTP server for fast, secure, and well-delivered transactional email communication.

Why Do We Recommend It?

Postmark stands out for its separation of transactional and promotional email traffic. While transactional emails are routed through a dedicated infrastructure to ensure fast and efficient delivery, promotional emails such as newsletters are processed through a parallel system. This approach ensures that transactional emails are not impacted by the high volume of promotional sends.

Who Is It Recommended For?

Postmark is recommended for businesses and developers who need a reliable SMTP server for sending transactional emails, such as password resets, account notifications, and user alerts, with fast and guaranteed deliverability. Its focus on transactional email makes it less suitable for businesses requiring robust marketing automation or bulk email services.

Pros:

Reliable Deliverability: Postmark is known for its exceptional email deliverability, prioritizing getting transactional emails into the inbox without delay or issues, which is crucial for time-sensitive communications.
Affordable Plans: Starting at just $15 per month for 10,000 emails, Postmark offers a cost-effective solution for businesses looking for dependable email services without breaking the bank.
Top-Notch Support: Postmark provides excellent customer support, offering email, live chat, and one-on-one calls at no extra charge.
Secure and GDPR Friendly: Postmark is committed to protecting user data and is fully GDPR-compliant.
Integrated Email Templates: Saves time on email design via its pre-designed, responsive email templates that look great in all major email clients, while ensuring professional and consistent branding.

Cons:

Focus on Transactional Emails: Postmark is less ideal for businesses looking for robust marketing automation features or bulk email capabilities due to its primary focus on transactional emails.
Lack of Marketing Features: Postmark does not offer advanced marketing features such as A/B testing, segmentation, or advanced automation.