7 Best Free SMTP Servers for 2025

Emails are a cornerstone of communication for both businesses and individuals in the digital age. Whether you're a small business owner, a marketer managing email campaigns, or someone in need of a reliable way to send bulk emails, choosing the right SMTP (Simple Mail Transfer Protocol) server is crucial.

SMTP servers serve as the backbone of email delivery that ensures your messages reach their recipients promptly and without errors. In this article, we’ll explore seven of the leading SMTP servers that offer generous free plans, including their key features, benefits, and ideal use cases to help you select the one that aligns perfectly with your needs.

Here is our list of the best free SMTP servers:

SendPulse SendPulse free plan allows users to send up to 15,000 emails per month to 500 subscribers
Mailjet The free plan offers a generous allowance of up to 6,000 emails per month.
SendGrid Offers 100 emails per day (3,000 emails per month) at no charge.
Mailgun The free plan allows users to send up to 100 emails per day (3,000 emails per month).
Mailtrap Allows you to send up to 1,000 emails each month and store up to 500 contacts in your account.
Aha Send The free plan offers up to 1,000 free emails per month
SMTP2Go Allows a free plan of 1,000 emails per month and a daily cap of 200 emails.

The Best Free SMTP Servers

Methodology Used for Our Selection

In selecting our top free SMTP servers, a combination of factors were considered to provide a well-rounded list. We consider factors such as reliability, security, and ease of use. We looked for services that offer high deliverability rates to avoid your emails being marked as spam. We also made sure that the server supports secure protocols (like TLS/SSL) to protect data.

Features like daily/monthly sending limits, IP reputation, and customer support were also prioritized, as these can impact the quality and sustainability of your email communication. Some free SMTP providers may impose restrictions on the number of emails you can send or the number of recipients per email, so choose one that fits your needs.

1. SendPulse

SendPulse offers a free SMTP server designed to help businesses test their email marketing strategies, improve engagement, and achieve results without incurring initial costs. With the free plan, users benefit from a drag-and-drop email builder and access to over 130 customizable templates, email address verifier to maintain clean mailing lists, 100 MB of image storage capacity, and segmentation capabilities for targeted campaigns.

Key Features:

Free Monthly Quota: Send up to 15,000 emails for free to 500 subscribers.
Drag-and-Drop Email Builder: Design emails with ease using a user-friendly interface and pre-made templates.
Segmentation and Automation: Segment audiences for tailored messages and set up automated workflows for efficient communication.
Email Address Verification: Keep your email list clean and improve deliverability.
Flexible Plans: Upgrade to subscription-based or pay-as-you-go plans as your needs grow.

Why do we recommend it?

SendPulse’s free SMTP server is an excellent starting point for individuals, startups, and small businesses looking to establish or refine their email marketing efforts. The platform's generous free tier provides the tools necessary to create professional campaigns, test strategies, and automate workflows without upfront costs.

Who is it recommended for?

SendPulse’s free SMTP server is ideal for startups, small businesses, freelancers, and individuals building their personal brands, as well as non-profits and organizations with limited budgets. It’s also well-suited for marketing teams looking to test automation workflows and segmentation strategies before upgrading to a paid plan.

Pros:

Generous Free Tier: Send up to 15,000 emails per month to 500 subscribers for free.
User-Friendly Tools: Intuitive drag-and-drop editor and access to 130+ templates for easy campaign creation.
Advanced Features in Free Plan: Includes segmentation, automation workflows, and email address verification, enhancing campaign effectiveness.
Flexibility for Growth: Offers seamless scaling to paid plans as your subscriber list or campaign needs expand.

Cons:

Subscriber and Storage Limitations: Limited to 500 subscribers on the free plan, with image storage is capped at 100 MB.
Advanced Features Require Paid Plans: More comprehensive analytics and premium tools may require upgrading to a paid plan.

2. Mailjet

Mailjet offers a free SMTP server plan designed for businesses and individuals with modest email-sending needs. With a monthly limit of 6,000 emails and a daily cap of 200 emails, it’s an excellent solution for startups, small businesses, or developers looking for a reliable and straightforward email platform.

Key Features:

1500 Contact Capacity: Manage up to 1,500 contacts within the free plan.
SMTP Relay and APIs: Seamless integration with applications using SMTP or APIs for sending emails.
Webhooks: Monitor and track email events in real time for better insights and troubleshooting.
Advanced Email Editor: Create professional, responsive email designs with an easy-to-use editor.
Basic Statistics: Access fundamental reporting metrics, including email delivery and engagement.
Form Builder: Build forms to capture user information or newsletter signups easily.
Forever Free Plan: Use the free tier indefinitely without the pressure of time-limited trials.

Why do we recommend it?

Mailjet’s free SMTP server is a reliable, cost-effective option for individuals and small businesses with modest email needs. Its generous allowance of 6,000 emails per month and advanced features like an intuitive email editor, API integration, and real-time webhooks make it a comprehensive solution for sending professional emails without spending a dime.

Who is it recommended for?

Consider the Mailjet free SMTP server plan if you’re an individual, SMB, or developer who requires a cost-effective and reliable solution for sending emails. It’s perfect for testing, managing modest email campaigns, or building forms for lead generation.

Pros:

Generous Monthly Limit: Offers up to 6,000 emails per month, suitable for low-volume users.
Developer-Friendly: SMTP relay, APIs, and webhooks ensure compatibility with various applications and programming languages.
No Expiry: Unlike trial plans, the free plan remains available indefinitely, providing stability for small-scale projects.
Contact Management: The capacity to manage 1,500 contacts is ideal for small mailing lists or customer bases.

Cons:

Limited Statistics: Basic reporting tools lack the depth and detail needed for advanced analysis.
No Advanced Features: Lacks premium functionalities like segmentation, automation, or advanced analytics.
Basic Support: Support options may be limited compared to those available for paid plans.

3. SendGrid

SendGrid is a cloud-based service founded in 2009 that provides email delivery and marketing solutions. SendGrid Free plan is available at $0 per month, providing basic email sending features for those with low-volume requirements. For more advanced features, the Essentials, Pro, and Premier plans offer additional capabilities.

Key Features:

Basic Analytics: The free plan includes basic analytics to track key metrics like open rates and click rates to help users optimize email deliverability.
Basic Email Support: While email support is available, users on the free plan may experience limited assistance compared to premium plans.
Proven Deliverability: SendGrid is known for its high inbox placement rates, and has minimal risk of emails being caught in spam filters.
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.

Why do we recommend it?

With the ability to send up to 100 emails per day, the Free Plan provides essential features such as email tracking, analytics, and deliverability optimization. The integration of SendGrid's API and SMTP relay makes it a convenient choice for developers who want to integrate email functionality into their websites or applications, without incurring cost.

Who is it recommended for?

We recommend SendGrid's Free Plan for individuals, developers, startups, and small-scale email marketers who do not require advanced features like dedicated IP addresses. It is also a good fit for those just getting started with email campaigns who need to test and optimize their email deliverability. subuser management, or custom domains.

Pros:

No Cost: The free plan offers 100 emails per day (3,000 emails per month) at no charge. This makes it attractive for small-scale email needs without incurring any cost.
Analytics & Deliverability Optimization: Provides basic email performance insights, which can help improve email campaigns even on the free plan.
Easy Integration: Includes access to SendGrid's API and SMTP relay for easy integration with applications and websites.
High Deliverability: SendGrid is known for strong deliverability rates, even for free users, ensuring that emails are more likely to land in recipients' inboxes.

Cons:

No Dedicated IPs: The lack of dedicated IP addresses in the free option means that email reputation may be affected, as you're sharing an IP with other SendGrid users.
No Subuser Management: Teams or users managing multiple email campaigns cannot assign roles or permissions to subusers, limiting collaboration for businesses.
No SSO: Without Single Sign-On, users may face challenges managing access securely, especially in teams with multiple users.

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. Mailgun’s Free Plan is an excellent option for users who want to test out the platform with no financial commitment. The plan allows you to send up to 100 emails per day, which adds up to roughly 3,000 emails per month.

Key Features:

100 Emails per Day: The free plan allows users to send up to 100 emails per day, or about 3,000 emails per month.
Ticket Support: Access to basic support via ticket-based assistance, which helps resolve issues, though higher priority support may be available in paid plans.
RESTful Email APIs and SMTP Relay: The free plan provides access to Mailgun’s RESTful email APIs and SMTP relay. This makes it easy to integrate email sending capabilities into your web applications.
Tracking, Analytics, and Webhooks: Includes basic email tracking and analytics (open rates, click rates), as well as webhooks for sending real-time event notifications.
1 API Key and Inbound Route: Provides access to one API key for integrating email features into applications, and the ability to manage one inbound route for receiving emails.

Why do we recommend it?

We recommend Mailgun for its ability to send 100 emails per day (or 3,000 emails per month) including RESTful APIs and SMTP relay capabilities. This offers ample capacity for transactional emails, simple marketing campaigns, or testing. The free plan also provides email tracking, analytics, and the ability to set up custom sending domains, all of which make it an excellent choice for those with modest email sending needs.

Who is it recommended for?

Mailgun’s Free Plan is suited for users who are just starting to explore email marketing or need a low-cost solution for transactional emails, or developers who want to integrate email features into their software without incurring costs. It is also a good fit for small businesses that have modest email volumes and don’t require advanced features

Pros:

Easy Integration: The inclusion of RESTful APIs and SMTP relay makes Mailgun an excellent choice for developers who need to integrate email functionalities into their applications and websites.
Custom Sending Domain: The ability to use a custom sending domain enhances professionalism and branding for users who want to send emails from their own domain.
Ticket Support: While limited, ticket-based support ensures that users can get assistance if issues arise.

Cons:

Limited Email Capacity: The free plan email capacity may not be sufficient for businesses with higher email volumes or more complex email needs.
Short Log Retention: The 1-day log retention can make it challenging to access detailed email activity data for troubleshooting or analytics beyond a short time frame.
No Advanced Features: More advanced features, such as dedicated IP addresses, advanced analytics, and higher email limits, are not available in the free plan.
Limited Support: The ticket support on the free plan may result in slower response times compared to the priority support available in higher-tier paid plans.

5. Mailtrap

Mailtrap’s Free Plan is a great option for professionals and companies looking to try out its email testing services without any financial commitment. The plan allows users to send up to 1,000 emails per month and manage 500 contacts, making it suitable for small-scale email testing or development projects.

Key Features:

1,000 Emails/Month: You can send up to 1,000 emails each month, which is suitable for small-scale email campaigns or testing purposes.
500 Contacts: Store up to 500 contacts in your account, just enough to manage and send emails to a modest list of recipients.
200 Emails/Day: The daily limit of 200 emails ensures you can run regular email tests or small campaigns, though it might not be sufficient for larger volumes.
3 Days Email Storage: Sent email bodies are stored for 3 days. This gives you a short window to review or test the content before it expires.
10MB Max Email Size: Each email, including attachments, can be up to 10MB, which is ideal for standard text or small media attachments.
Email Testing (100 Emails): You can test up to 100 emails per month using Mailtrap’s Email Testing feature, which helps ensure proper delivery before sending out real campaigns.

Why do we recommend it?

With 1,000 emails per month and 500 contacts, Mailtrap free plan is sufficient for small-scale testing or limited email marketing needs. The 3-day email storage and 10MB max email size are sufficient for basic email troubleshooting, while the Email Testing feature with 100 test emails provides a valuable tool for ensuring email deliverability before sending to recipients.

Who is it recommended for?

Consider Mailtrap free plan if you’re looking for a cost-free option to test email functionality and performance without exceeding basic sending limits. It’s great for development and marketing teams. However, for larger email campaigns or growing contact lists, the plan’s limits may require upgrading to a paid option for more extensive testing and sending.

Pros:

Free to Use: Ideal for professionals or companies who want to try Mailgun’s services with no cost.
Ample Monthly Email Quota: 1,000 emails per month offers good flexibility for small projects.
Easy Testing: The Email Testing feature is available to try out, with 100 emails per month included.
Generous Storage: 3 days of email storage to review and test email content.

Cons:

Daily Email Limit: The 200 emails/day limit may be restrictive for larger campaigns.
Short Email Storage Period: Emails are only stored for 3 days, which may not be enough for extended review or troubleshooting.
Email Size Limit: The maximum email size of 10MB, including attachments, may be limiting for certain types of emails.

6. AhaSend

AhaSend offers a robust and flexible free SMTP server plan ideal for sending transactional emails. With a generous allowance of 1,000 free emails per month, this plan is perfect for small businesses, startups, or developers who need reliable email delivery without upfront costs.

Key Features:

1,000 Free Emails/Month: Perfect for low-volume users, with additional options for scaling as your needs grow.
Pay-As-You-Go Pricing: After the free tier, pay $5/month for up to 10,000 emails, then $0.50 per 1,000 additional emails.
Unlimited Functionality: Includes unlimited domains, team members, webhooks, and message routes, ensuring no feature is restricted by usage volume.
Advanced Capabilities: Offers open and click tracking, automated bounce and blocklist management, spam monitoring, and team access management.
Secure and Flexible Sending Options: Supports multiple SMTP ports (25, 587, 2525) with mandatory STARTTLS encryption for enhanced security.

Why do we recommend it?

AhaSend’s free SMTP server is tailored for transactional emails, combining speed, reliability, and security. Whether you’re sending OTPs, account confirmation emails, or notifications, AhaSend’s powerful infrastructure ensures emails reach the inbox efficiently and securely.

Who is it recommended for?

AhaSend is particularly recommended for transactional email use cases where speed, reliability, and scalability are crucial. However, it is less suited for bulk marketing campaigns or high-volume promotional emails, as its infrastructure is optimized for transactional purposes.

Pros:

Completely Free Tier: Ideal for small-scale users sending up to 1,000 emails monthly.
Full Access to Features: No matter your usage, you get priority support and all premium features.
Lightning-Fast Delivery: Exceptional speed for transactional emails, ensuring OTPs and confirmations are received promptly.
Scalability: Seamlessly transition to higher usage with predictable pricing.
Developer-Friendly: Supports integration in any programming language with native SMTP support and flexible inbound routing.

Cons:

Limited to Transactional Emails: AhaSend does not support bulk marketing emails, focusing solely on transactional communication.
Free Tier Cap: Businesses with higher email-sending needs may quickly outgrow the 1,000-email free limit.
Dependent on SMTP Knowledge: While the service is straightforward, users may need some familiarity with SMTP to fully leverage its features.

7. SMTP2Go

SMTP2GO’s free plan provides a simple and reliable solution for users with low-volume email-sending needs or those looking to test the platform. With a monthly sending limit of 1,000 emails and a daily cap of 200 emails, it’s an excellent starting point for small-scale operations.

Key Features:

Unlimited Timeframe: Use the free plan as long as you require without a time limit.
Email Queuing: Emails exceeding the daily limit are queued and sent when quotas reset, but any above the monthly limit are rejected.
Basic Reporting: Access spam, bounce, open, click, and unsubscribe reports for the past 5 days.
Domain and Email Verification: Add up to 5 verified sender domains or single email addresses to ensure reliable sending.
Limited Team Access: Allows up to two team members and one webhook for integrating email data.
Ticket-Based Support: After 14 days, free plan accounts are limited to ticket support only.

Why do we recommend it?

The SMTP2GO free plan offers an excellent entry point for individuals and small businesses seeking a reliable and user-friendly email-sending solution. With a monthly allowance of 1,000 emails and a daily cap of 200, this plan is ideal for users with modest email requirements or those testing the platform. SMTP2GO ensures seamless integration with tools like SMTP relay and provides basic but essential features such as detailed email tracking and reporting

Who is it recommended for?

The SMTP2GO free plan is ideal for individuals, startups, or small businesses with minimal email-sending requirements. It’s also a great choice for users who want to test the service before committing to a paid subscription. However, if you require more advanced capabilities or higher email volumes, consider upgrading to a paid plan.

Pros:

No Expiry: The free plan remains active indefinitely, making it a great option for long-term testing or low-volume sending.
Fair Usage Policies: Queuing emails that exceed daily limits ensures a smooth user experience without disruptions.
Easy to Get Started: Simple verification of sender domains or email addresses ensures a quick setup.
Scalable: Upgrading to paid plans removes limitations and unlocks advanced features when higher volume or functionality is needed.

Cons:

Limited Reporting Access: Free plan users can only access email activity reports for the past 5 days, compared to up to 2 years for paid accounts.
Restricted Features: Advanced tools like SMS messaging, email archiving, and scheduled reporting are unavailable on the free plan.
Support Limitations: After the first 14 days, support is restricted to ticket submissions, which may delay issue resolution.