An SMTP server is an essential part of sending emails. It can easily handle high-volume sending, be it marketing campaigns, email newsletters, simple welcome or transactional emails. However, it requires robust infrastructure to operate properly.
Fortunately, most email service providers (ESPs) have free SMTP servers that are a good way to get started. As your business grows, you can move on to the paid plans to scale your infrastructure.
We’ve analyzed dozens of worthwhile solutions and picked 13 free SMTP servers you can rely on.
Is a cloud-based SMTP server what you need?
In the following blog post, we’ll be talking about cloud-based SMTP servers. This is the most optimal option for numerous businesses and startups. It requires fewer resources compared to a self-hosted SMTP server. Usually, only large corporations can afford it and even they are choosing cloud-based services. The main reasons include:
- Cost-efficiency: A cloud-based server is a good bargain. You will have to spend so much more to create and maintain your own email infrastructure. Besides, the options below provide free subscription plans.
- Deliverability: Cloud-based SMTP services incorporate security mechanisms and anti-spam measures. This ensures that your emails are delivered to the inboxes instead of spam folders. You can read more about this in our dedicated blog post about email deliverability.
- Scalability: Your email campaign may have thousands or even millions of recipients. This is not a problem for the cloud-based infrastructure as it’s designed with scalability in mind. The services can easily adjust to your growing emailing needs without causing delays in sending or delivery.
- Security: Cloud-based SMTP servers can’t be damaged physically and are essentially extremely secure against virtual threats. On-premise servers, on the other hand, require protection against physical damage and have to be configured really well to withstand digital attacks.
What is the difference between an SMTP server, SMTP relay, and SMTP service?
An SMTP server is a computer program or an app that sends or relays outgoing emails using the Simple Mail Transfer Protocol.
From a technical standpoint, SMTP relay is the process of delivering email from one email server to another. SMTP relays are essential to send out all forms of bulk mail, transactional emails (password resets and registration confirmations, for example), newsletters, etc. In the context of email marketing, SMTP relay services usually refer to the actual SMTP servers.
SMTP service is a general notion that denotes an off-the-shelf email infrastructure that includes one or several SMTP servers. In that case, your ESPs are considered as SMTP service providers.
Providers offering free SMTP servers: comparison table
|Name||Type of provider||Number of free emails||Pricing|
|Gmail SMTP server||SMTP server||500 emails per day||– Google Workspace Business Starter ($6/user/month)|
– Google Workspace Business Standard ($12/user/month)
– Google Workspace Business Plus ($18/user/month)
– Custom Enterprise plan(2k emails and 2k unique external recipients per day for all these plans)
|Mailtrap||Email delivery platform||1,000 emails per month||– Individual (starts at $10/month for 10,000 emails)|
– Business (starts at $85/month for 100,000 emails)
– Enterprise (starts at $750/month for 1.5M emails) – Custom (custom offer for more than 5M emails)
|MailerSend||Email sending service||12,000 emails per month||– Premium (starting at $25 for 50,000 emails/month and $0.90 per additional 1,000 emails)|
– Enterprise (custom plan)
|Elastic Email||Email sending service||100 emails per day||Pay-as-you-go:|
– Email API ($0.10 per each 1,000 emails plus 0.50/day)
– Email API Pro – $0.15 per each 1,000 emails plus $1/day
Monthly plans with email marketing features:
– Marketing (starts at $18/month for 5,000 contacts)
– Marketing Pro (starts at $60/month for 10,000 contacts)
|Mailjet||Email sending service||6,000 emails per month200 emails per day||– Essential (starts at $15 for 15,000 emails)|
– Premium (starts at $25 for 15,000 emails)
– Enterprise (custom offer for more than 500,000 emails)
|TurboSMTP||SMTP server||6,000 emails per month200 emails per day (for 12 months)||Pay-as-you-go:|
– Starts at $49 for 50,000 emails (valid for 1 year)
– Basic (starts at $14.95 for 50,000 emails)
– Professional (starts at $79.95 for 200,000 emails)
– Enterprise (custom pricing for more than 2M emails)
|Mailgun||Email sending service||5,000 emails for 1 month300 emails per day||– Foundation ($35/month for 50,000 emails)|
– Scale ($90/month for 100,000 emails)
– Custom (custom email volume and pricing)
|Sendinblue||Marketing platform||300 emails per day||Marketing plans:|
– Starter (starts at $25/month for 20,000 emails)
– Business (starts at $65 for 20,000 emails)
– Enterprise (custom email volume and pricing)
Transactional emails start at $15/month for 20,000 emails
|SendPulse||Marketing platform||15,000 emails per month for free marketing plan 12,000 emails per month for free transactional email plan||Marketing plans: |
– Monthly subscriptions (the cheapest option starts at $9.97/month for 500 contacts)
– Pay-as-you-go (the cheapest option starts at $25.80 for 10,000 emails)
– Monthly subscriptions (the cheapest option starts at $8.15/month for 25,000 emails)
– Pay-as-you-go (starts at $12.22 for 10,000 emails)
Note: the pricing on SendPulse is displayed in Russian Rubles. We converted them manually to USD and there may be slight differences depending on the exchange rates
|SendGrid||Email service provider||100 emails per day for transactional emails 2,000 contacts and 6,000 emails for marketing campaigns||Email API: |
– Essentials (starts at $19.95/month for 50,000 emails)
– Pro (starts at $89.95/month for 100,000 emails) – Premier (custom offer)
– Basic (starts at $15/month for 15,000 emails and 5,000 contacts)
– Advanced (starts at $60/month 50,000 emails and 10,000 contacts)
|Amazon SES||Email sending service||62,000 emails per month (from an app hosted in Amazon EC2)||Pay-as-you-go:|
– $0.10 for every 1,000 emails- $0.12 per GB of data in the emails you send
– $24.95/month for a dedicated IP address
|SMTP2GO||SMTP server||1,000 emails per month||– Starter (starts at $10/month for 10,000 emails)|
– Professional (starts at $75/month for 100,000 emails)
-Premier (custom pricing for over 3M emails/month)
|Netcore Email API (formerly Pepipost)||SMTP server||30,000 emails free for the first 30 days.Then 100/day free forever||-$17.50/month for 150,000 emails |
-$59.50/month for 400,000 emails
-$101.50/month for 600,000 emails
-$311.50/month for 2M emails
Gmail SMTP server
Let’s start with the best known free SMTP service. Anyone who has a Gmail account can send emails using Google’s free SMTP server. So, it’s not just for personal messages. You can use the Gmail SMTP server for notifications, contact forms, and anything else you need for your web app.
This service is a perfect solution for individuals or small businesses that do not plan to send high volumes of emails. The Google SMTP server is totally free of charge, but it has some limitations (refer to their documentation for more info). Currently, you can send up to 500 emails per day with a free Gmail account or a free trial of Google Workspace.
Once you’ve reached one of these limits, email sending will be blocked for up to 24 hours. To increase the limits, you can sign up for a paid Google Workspace account. You can learn about the available plans, pricing, and features here.
The Gmail SMTP server is a free and useful solution for sending emails but it’s not an option for bulk emails. It doesn’t provide control over your DNS records which means you won’t be able to set up authentication protocols. Plus, bulk emails coming from @gmail.com addresses will most probably be considered as spam by ISPs. The same goes for the free SMTP server offered by Microsoft Outlook.
So it’s better to opt for SMTP email service providers that offer free SMTP servers.
Email Sending is an email infrastructure with high deliverability rates by design. It has both solutions: Email API and SMTP service to integrate easily with your app. Email Sending has unique monitoring capabilities to ensure effortless maintenance and troubleshooting. The free tier allows users to send up to 1,000 emails per month.
- Actionable analytics with helicopter-view dashboards
- Drill-down reports for mailbox providers
- Easy integration with ready-made configurations for PHP, Python, Java, and other programming languages
- Up to 60 days of email logs (7 days for free tier)
- Deliverability alerts to troubleshoot unexpected sending issues if they occur
- Suppression management
- Transactional email templates with HTML and text editors
- Dedicated IP with automatic IP warmup (paid)
- 1,000 or more team members (paid)
Mailtrap Email Sending has transparent pricing plans. If you need to send more than 1,000 emails, you can choose between Individual, Business, Enterprise, or Custom plans. Individual starts at $10 for 10,000 emails. Additional emails will cost you $1 per 1,000.
- When you first sign up and verify your domain, the hourly throughput is limited to 50 emails. The restriction is lifted once your domain is reviewed. This is the security measure to prevent spam abuse;
- The maximum number of concurrent SMTP connections per account is 10.
MailerSend is a transactional email and SMS service built for developers. It allows them to implement transactional messaging into their stacks quickly and easily. Yet the design is suitable even for non-technical teams so that they can contribute to the content, design, or business messaging. MailerSend can be integrated with your app through API or SMTP.
- SMTP and RESTful API
- Email verification
- Suppression list management
- Email tracking and analytics
- Drag and drop, HTML and rich text email builders
- Dedicated IPs (paid)
- Inbound routing (paid)
- Transactional SMS (paid)
You can get started with MailerSend’s Starter – a free plan which includes 12,000 emails per month and access to the SMTP, email API, and email support. If you need to send more, additional emails are charged at a rate of $1.00 per 1,000.
For a sending volume of 50,000 emails or more, you should upgrade to a Premium plan. The pricing starts at $25 for 50,000 emails, 100 SMS, and 100 email verification credits. Additional email pricing starts at $0.90 per 1,000 emails and is charged at decremental rates for higher volume plans. The Premium plan includes advanced features such as inbound routing, transactional SMS, live chat suppport, and higher usage limits.
You can’t send more than 12,000 emails/month with a free plan. Daily API requests are limited to 1,000.
Elastic Email offers an email marketing platform along with an email delivery engine that can be connected for sending emails via HTTP API or SMTP.
- SMTP and RESTful API integration
- Subscription forms, popups, and landing pages for building contact lists
- Analytics with real-time delivery monitoring, unsubscribe insights, and activity reports
- Email templates and drag-and-drop editor
- Email verification (paid)
- Private IP addresses (paid)
You can start using Elastic Email with a free trial, which allows you to send up to 100 emails per day. This may be enough at the outset of your project. Over time, you’ll need larger volumes of emails. For this, Elastic Email provides pay-as-you-go pricing plans for Email API:
- Email API
- $0.10 per 1,000 emails plus $0.50 per day
- Email API Pro
- $0.15 per 1,000 emails plus $1 per day
The email marketing toolkit is available with a monthly plan that allows sending an unlimited number of emails with their Email Delivery Engine. Instead, you pay for the number of contacts. The marketing tool starts from $18/month per 5,000 contacts.
You cannot send more than 100 emails per day for free. You also need to verify a sender in order to send over 500 emails per day.
SMTP limits are:
- Up to 20 concurrent requests from a single IP
- A single command timeout is 2 minutes
- Multiple emails can be submitted in one session
API connection limits include:
- Up to 20 concurrent requests from single IP
- Connection timeout is 600 seconds
Mailjet is an email service provider that allows users to design and send marketing campaigns and transactional emails. It is mainly suitable for developers and marketers.
Mailjet has a free SMTP server to offer. It is represented as an SMTP relay server that you can easily integrate within your app. Unlike similar solutions, Mailjet supports several SMTP ports. In practice, this increases the security of your emails with TLS or SSL encryption and prevents your emails from getting blocked by internet service providers (ISPs). If you prefer a conventional HTTP connection, Mailjet Send API is also available.
- APIs, SMTP Relay, Webhooks
- Support for multiple SMTP ports
- High inbox placement rate
- Real-time dashboard for monitoring email performance
- Transactional email templates and editor
- Dedicated IP (paid)
- A/B testing (paid)
- Multi-user collaboration (paid)
If you want to try this service, you can make use of 6,000 emails per month. You’ll get them for free without any expiration period or having to provide any credit card details. If you need more email volume, then you’ll have to select one of the subscription plans: Essential, Premium, or Custom. The Essential plan starts at $15 for 15,000 emails per month and includes both SMTP and email editor.
The free trial subscription is limited to sending 200 emails per day. The contact list is also limited to 200 addresses.
turboSMTP is a reliable and cost-effective SMTP service. It provides a free version with 6,000 emails per month for one year. Take a look at the features this SMTP server offers.
- Real-time email campaign tracking
- The ability to send email marketing campaigns or transactional notifications
- Email template creator
- Email validation
- 24/7 customer support for free and paid plans
- Subuser management (paid)
- Dedicated IP address (paid)
turboSMTP provides both monthly and pay-as-you-go plans. The latter allows you to purchase prepaid credits and use them only when you need to send emails. For example, you can buy 100,000 emails for $92 and send them at any time for one year. If you deal with recurrent email sending, consider the Basic or Pro plans for your business. The cheapest option costs $14.95/month for 50,000 relays.
With the free plan, you can send up to 200 emails per day.
Mailgun is another email service provider (ESP) that offers a free SMTP server and allows developers/marketers to send transactional and marketing emails. The simplest way to get started with sending emails is to use the SMTP relay service. For this, you need to:
- Add and verify your domain name
- Choose between a dedicated or shared IP address
- Set up your SMTP server
The SMTP configuration of your app should be tweaked with your username, password, hostname, and port of the SMTP server. Another option is the SMTP API, which significantly improves email handling.
- Email API, SMTP Relay, and Webhooks
- Email tracking and analytics
- Suppression management
- Drag-and-drop template builder
- Dedicated IP (paid)
- Email address validation (paid)
As for pricing, you get 5,000 free emails for 1 month. When you need more, you can purchase a subscription plan. The cheapest plan starts at $35 for 50,000 emails.
Mailgun also has a pay-as-you-go option (Flex plan) but it’s not listed on their pricing page. You can only access it if you submit your credit card information or while downgrading from Foundation or other paid plans. Flex costs $1 for every 1,000 emails you send per month.
Despite allowing 5,000 free emails per month, all new domains are included in the sandbox and you can’t create custom domains. This limits the email sending to 300 emails per day and you can only send to 5 authorized recipients.
Sendinblue is a bulk email service. It provides different tools for optimizing marketing workflow. One of them is the SMTP relay. This is a professional server to deliver transactional emails sent from your web app. Besides the SMTP server, you can opt for API and plugins for eCommerce stores or a WordPress site to set up your bulk email sending.
- Real-time reporting
- Advanced templating language based on Django
- Drag-and-drop template builder
- APIs, webhooks
- Multi-user access (paid option)
- Heat map reporting (paid option)
- Dedicated IP address (paid option)
The free plan allows users to send 300 emails per day. This can be enough for individuals or small businesses, but it’s not sufficient for sending large-scale bulk emails. There is no pay-as-you-go option with Sendinblue and they have different pricing plans for marketing and transactional tools.
For marketing, you can choose between Starter (from $25 for 20,000 emails), Business (from $65 for 20,000 emails), and Enterprise plans with custom limits and pricing. Transactional Email starts from $15 for 20,000 emails/month and goes up to $550 for 1M emails/month. There’s also an option to get a custom plan if you have a higher sending volume.
Your daily limit is 300 emails. Also, for Transactional Email users with shared IPs, there is a quota of 100 emails per hour. This bandwidth limit goes up or down automatically based on your engagement metrics and sending volume. Marketing automation is also limited to 2,000 contacts in the free plan.
SendPulse is another service for email marketing and transactional emails. It provides an SMTP server for all types of emails. You can integrate it with your app or other system and send transactional emails quickly, securely, and for free. SendPulse offers 12,000 emails per month at no charge!
- High deliverability due to good sender reputation
- APIs and webhooks
- Email template creator
- DKIM and SPF authentication
- Delivery reports and open and click tracking
- Unsubscribe monitoring
- Dedicated IP (paid)
As we said, you get 12,000 free transactional emails per month. If you want more, you can either pay for additional emails (for example, 10,000 for $12.22) or purchase a subscription plan: Basic, Pro, or Enterprise. The price for each plan differs according to the email volume you need. For example, Basic with 25,000 emails will cost $8.15/month. They offer different pricing plans for Email Marketing.
You can’t send more than 400 emails per day with the free plan and the hourly limit is set to 50 emails using 2 sender domains. This value goes up significantly if you use a subscription plan or buy additional emails with the pay-as-you-go option. For example, with the Basic plan (25,000 emails), your bandwidth limit is 2,500 emails per hour. If you buy 25,000 emails with pay-as-you-go, the limit will be 4,000 emails per hour.
Note, however, that email size matters for pay-as-you-go emails – emails bigger than 100 Kb are counted as multiple emails.
SendGrid is a renowned email delivery service. To see how it compares with other services, you can check out our Sendgrid vs. Mandrill vs. Mailgun article. In short, SendGrid is a cloud-based SMTP provider. It offers SMTP Relay, Web APIs, and Webhooks for sending transactional and bulk emails.
- Email authentication
- Delivery optimization tools
- Deliverability insights and analytics
- Dynamic template editor
- Dedicated IP address (paid)
- Subuser management (paid)
- Email validation (paid)
SendGrid’s free plan provides 100 emails per day forever. If your email volumes are big, check out one of the paid subscription plans: Essentials, Pro, and Premier. Essentials plan starts at $19.95 for 50,000 emails. By the way, the prices are estimated, so taxes and overages may apply.
You can’t send more than 100 emails per day with the free plan.
Amazon SES (Simple Email Service) is a cloud-based platform for businesses that use email to communicate with their users. It provides several email sending interfaces:
- SMTP interface
- API via AWS SDK or AWS CLI
You can use the SMTP interface to integrate Amazon SES into your app, email client, ticketing system, or other software.
- Several methods to monitor email sending activity
- Sender reputation dashboard
- Flexible email receiving
- Mailbox simulator to test email sending
- Support for industry-standard authentication mechanisms: SPF, DKIM, and DMARC
- Personalization of emails
- High deliverability
- Dedicated IP address for exclusive use (paid)
The pricing system includes no upfront costs or subscriptions. Users pay $0.10 for every 1,000 emails sent or received. Data in the emails is paid in addition: $0.12 per gigabyte. Amazon SES provides a free usage tier for the first 62,000 emails sent each month, but these emails must be sent from an app hosted on Amazon EC2. The first 1,000 emails received are also free.
All new accounts are placed in the Amazon SES sandbox, which means there are sending limitations. According to these, you can send up to 200 emails at a rate of 1 email per second per 24 hours. You can increase your sending limits by moving out of the sandbox.
If you are interested in this SMTP service, read our dedicated blog post.
SMTP2GO is a reliable SMTP server that has handled email delivery for its customers since 2006. You can start for free with 1,000 emails per month.
To send emails with SMTP2GO, you need to integrate it with an email-sending tool or app.
- Solid deliverability
- Robust reporting
- Understandable API
- Email testing tools for spam checks and email previews in various email clients (on advanced plans)
For everything between 1,000 and 40,000 emails per month, they offer the Starter plan for $10-15 per month. The price depends on whether the emails you send are within the subscription plan limit or purchased as extra emails. The Professional plan starts at $75/month for 100,000 emails and adds a dedicated IP along with email testing tools. For high-volume senders who require more than 3M emails per month, they offer custom pricing.
With the free plan, you can send up to 200 emails per day and 25 emails per hour (this limit will be lifted once you verify your domain). Note that SMTP2GO applies strict rules for email lists over 100 email addresses to prevent spam. They take their sending reputation seriously to keep their IPs out of blacklists.
Netcore Email API (formerly known as Pepipost)
Netcore Email API (formerly Pepipost) is an email delivery service that you can integrate with your email sending tool or app as an SMTP server, or access its functionality via API and send bulk and transactional emails from your domain. It is more suitable for developers rather than marketers because Netcore Email API doesn’t offer an email builder or templates.
Netcore Email API offers a generous forever free plan. To test all the capabilities of the tool, you get 30,000 emails for the first month, and after that you’ll be able to send 100 emails per day for free.
- Real-time event tracking with webhooks
- High deliverability rates with Machine Learning and Artificial Intelligence algorithms
- Reliable infrastructure with authentication protocols
- Email logs for up to 90 days
The price depends only on the number of emails you send — all features are included in every plan. Everything between 30,001 and 150,000 emails costs $17.50 per month and $0.60 for 1,000 emails if you need extra. The next plan includes 400,000 emails for $59.50 and $0.55 for 1,000 extra emails. 2M emails will cost you $445 per month.
On the free plan, you are limited to 100 emails per day. After upgrading, this limit increases to 1,000 emails per day. This limit can be increased automatically based on the emails’ performance. It depends on the volume of emails you send, their quality, recipients’ engagement, etc.
Which service allows you to send 10,000 emails at once for free?
Let’s be realistic — none of the services will let you send 10,000 emails at once for free. Besides, such a volume of emails sent from a single email address in one go will definitely trigger spam filters. So, the best way is to split the email campaign into five batches of 2,000 emails each.
Out of all the services mentioned above, only seven allow you to send such a volume of emails for free. These are MailerSend, Mailjet, turboSMTP, Amazon SES, Mailgun, SendPulse, and Netcore Email API. But all of them have daily sending quotas or other limitations. SendPulse could be an option, but with its limit of 50 emails per hour, it will take you 200 hours for the entire campaign!
When and why should you opt for a fake SMTP server instead of a real one?
A fake SMTP server is useful for testing purposes as it allows you to check the email sending capability of an app without spamming users. Instead of spending time and resources on creating dummy email addresses, you can simply use a fake SMTP server and deliver emails to the virtual inbox.
You’ll need Mailtrap Email Testing for that task. It’s an Email Sandbox that allows developers to inspect and debug emails in staging environments. With its help, there’s no risk of spamming real inboxes – all the SMTP traffic is captured in the virtual inbox.
Apart from testing the email-sending functionalities, Email Testing enables users to check HTML/CSS and correct lines of code that won’t be supported by email clients, view and analyze Spam Score, check if their domain has been blacklisted, and preview emails.
And since this blog post is about free SMTP servers, Email Testing also has a free tier with the ability to test 100 emails.
When choosing between the free SMTP servers we listed, opt for the providers that have the highest delivery rates, offer scalable infrastructure, and have little to no downtime. The free options do provide a good opportunity to take a test drive and figure out which email providers will be the best match for your business in the long run.