9 Best SMTP Email Services for Reliable Delivery in 2025

SMTP stands for Simple Mail Transfer Protocol. This technology is best described as the postal service for emails. That’s because SMTP determines the servers where your emails will go and how they get there.

Essentially, SMTP determines the success of your email efforts. This is particularly crucial for brands or businesses that send bulk emails to their clients. An SMTP that is not configured correctly can result in high email bounces. Not only that, but it can also lead to spam reports, which will ultimately affect your email deliverability.

In this article, we’ll share nine of the best SMTP email providers, showing you what measures they take to help you maintain a high deliverability rate for your mass email campaigns. 

What is SMTP?

SMTP, or Simple Mail Transfer Protocol, is the technology used by mail servers to help you send an email and ensure that it reaches the recipient’s mail servers and is delivered into their inbox fast and reliably. 

SMTP maintains efficient email communications. That’s why the technology is available both for free and as a paid service. For example, email clients like Gmail and Outlook provide SMTP for free to support email communications.

However, there are limitations to the free SMTP you get from such providers. For example, they have daily sending caps, limited customization options, and strict anti-spam policies. That’s why, although the free SMTP services from such providers are great for everyday use, they’re not ideal for businesses that send bulk emails.

So, if you are a business that sends high-volume emails daily, you’ll need a reliable SMTP relay service. 

Let’s talk about those SMTP providers next.

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What is an SMTP email service?

SMTP email service providers take care of the SMTP protocol for you to ensure that your SMTP servers are set up correctly so that you can send and receive emails without any problems. 

SMTP providers will maintain the Simple Mail Transfer Protocol to secure your emails and ensure optimal deliverability while adhering to relevant anti-spam and privacy regulations. 

One of the best things about SMTP providers is that they allow businesses to send emails at scale. They also support automations and provide customization options. This helps eCommerce businesses deliver automated transactional emails, for example. It also enables you to run personalized email marketing campaigns.

Best SMTP providers in 2025

Below are the nine best SMTP providers on the market today:

1. GetResponse

GetResponse is a marketing platform with an email marketing solution, autoresponders, and other marketing tools. Our platform provides SMTP services through the GetResponse Max package.

GetResponse Max is a special package tailor-made for enterprises. This package gives you access to an SMTP server that you can integrate with your eCommerce store to send transactional emails. 

Our solution integrates with various eCommerce platforms, including WooCommerce, Magento, Shopify, Shoper, and Zapier. 

Deliverability is also not an issue with GetResponse. We guarantee a 99% deliverability rate. And if you’re looking for mass campaigns, GetResponse Max lets you send up to 5 million emails per hour with no problem. 

The best part about using GetResponse Max for your SMTP server needs is that you’ll also have access to other advanced marketing tools. For example, it supports advanced personalization, segmentation, and automation. 

You’ll also gain access to AI-powered product recommendations. This tracks and predicts customer behavior to send personalized recommendations for higher conversions. 

GetResponse features

• Responsive customer support – We provide customer support through four channels: live chat, email, phone, and Slack. We also offer support in eight different languages. Customer reviews on G2 praise us for being one of the most responsive marketing platforms.
• Advanced security – Your data is stored on multiple secure servers that are backed up daily and monitored 24/7. Our platform is also GDPR and CAN-SPAM Act compliant.
• Extensive integrations – GetResponse connects with over 170 business tools, from eCommerce platforms like Shopify and Magento to payment processing providers like Stripe and PayPal. We also have an open API you can use for custom integrations.
• Additional marketing tools – You’ll get access to advanced marketing tools like a webinar builder, an AI-powered website builder, a conversion funnel, and a content monetization tool for course creators.

Setting up the GetResponse SMTP is also straightforward. You can learn how to do it on our documentation here.

Pricing

Get in touch with our team to receive custom price tailored to your specific needs.

2. Sendgrid

SendGrid provides a cloud-based SMTP service to help you send emails at scale while maintaining decent deliverability rates.

The platform provides two SMTP services. They have the SMTP relay services you can plug into to access and use their SMTP protocol. However, this option tends to be less flexible and slower when sending plenty of emails.

The second option is the RESTful API, which can be faster and more reliable when sending emails at scale.  

Sendgrid features

• Scalable – SendGrid can be a great enterprise SMTP provider because it supports large volumes of email sends.
• API documentation – The platform provides documentation to help you with setting up the SMTP. However, quite a number of users have complained that it is still not the easiest SMTP to work with.
• Dedicated IP address – You’ll get a dedicated IP address to manage your sender reputation. It also automates IP warmup. But this feature is only available on the $89.95/mo Pro plan.
• Real-time analytics – Every plan provides real-time data analytics to help you understand the performance of your campaigns.

Pricing

SendGrid offers a 60-day free trial. However, you’ll be limited to just 100 emails per day during this time. 

Paid plans start at $19.95. This plan pushes your email limit to between 50,000 and 100,000 per month. However, this plan does not include dedicated IP addresses. 

For dedicated IP addresses, you must upgrade to the Pro plan, which costs $89.95/mo and supports 100,000 to 2.5 million email sends per month. 

The platform also provides a Premier plan customized to your specific needs.  

3. Brevo

Brevo is a marketing platform with various solutions, including an email marketing tool, SMS & WhatsApp marketing solution, automation tools, sales platform, and customer relationship management.

Among the other tools they provide is an outgoing mail server you can connect to and send your emails. The platform offers SMTP, webhooks, and a RESTful API to help you send emails. 

On top of that, you can get dedicated IP addresses to help you maintain a stellar sender reputation for better email deliverability. 

Brevo also supports automation workflows that you can use to automate email campaigns based on user behavior. You can use these automations for SMS and WhatsApp marketing campaigns. 

Brevo features

• Integrations – Brevo integrates with WordPress and eCommerce platforms.
• Email tracking – The platforms track your emails and deliver detailed reports to show campaign performance.
• Drag-and-drop editor – You can use the visual editor to customize and design emails quickly. They also provide a template library with emails for different industries and campaigns.
• Unlimited log retention – Logs do not expire on Brevo.

Pricing

Brevo offers a free SMTP server that supports up to 300 emails per day. You can upgrade to the paid plans that start at $9 per month to unlock more features like 5,000 email sends/mo and 24/7 email support.

That said, you must spend at least $16.17 per month on the Business plan if you want advanced analytics and priority support. 

One thing to keep in mind is that a dedicated IP is sold as a separate add-on, even on the Business plan.  

Seamless eCommerce integration with GetResponse

Power your online store with reliable transactional emails. GetResponse Max SMTP integrates with major eCommerce platforms including WooCommerce, Magento, and Shopify.

4. Postmark

Postmark is an email delivery service by ActiveCampaign. Among the several features they provide is an SMTP server and email APIs.

Postmark can help you send transactional emails and other critical business emails like password resets and email notifications quickly and reliably. The platform has also built several parallel infrastructures for the different email needs. 

For example, transactional emails are not mixed with promotional emails. Instead, they send these campaigns on separate sending infrastructures (streams) to enhance deliverability and safeguard your reputation.

Postmark features

• Email API – Postmark provides a well-documented email API that developers can use to send bulk emails from their applications. This includes the RESTful email API.
• Webhooks – Use webhooks to receive notifications regarding your campaigns, such as bounces, opens, clicks, spam complaints, and deliveries.
• Security – Postmark uses several security features to protect your data. They support 2FA, have secure data centers, and follow security best practices like advanced user permissions and DKIM, DMARC, and SPF support.
• Rebound – This feature allows you to notify users on your web app when they try to use an email address that has been marked as inactive. This helps reduce invalid email addresses and optimize deliverability.
• Detailed analytics – You’ll have a detailed analytics dashboard showing the performance of your email campaigns. The data is stored for 45 days by default, but you can reduce or increase the duration to up to 7 days or 365 days, respectively.

Pricing

Postmark has a free plan that lets you send up to 100 emails per month.

The Basic Plan starts at $15 per month. It accommodates up to four users, five servers, 15 streams, and 10,000 monthly emails.  

Pro plan costs $60.50 per month and supports 50,000 emails monthly, 6 users, 10 servers, and 30 message streams. 

Finally, you have the Platform plan, which costs $138/mo. That plan is designed for large teams and agencies. You get 250,000 emails per month and unlimited users, servers, and message streams. 

Postmark offers several features as separate add-ons. For example, you can get a dedicated IP for $50 per month. DMARC monitoring is also available for an extra $14/month.  

5. Mailgun

Mailgun provides transactional email delivery service and APIs to developers. The platform also provides a cloud-based SMTP relay service that helps businesses send SMTP emails without having to manage their own SMTP servers.  

The platform supports authentication protocols like SPF, DMARC, and DKIM to maintain the reputation of your brand and ensure inbox placement. 

One limitation with Mailgun is that it requires some technical expertise to set up and use. The whole platform focuses mostly on developers, which means non-tech-savvy folks will have a hard time using it. 

Mailgun features

• Real-time tracking – The platform tracks email performance to deliver detailed analytics on bounces, open rates, and clicks. You’ll also get logs showing campaign issues.
• Inbound routes – This helps you manage inbound emails much better by automatically grouping incoming auto-replies, forwarding emails that meet a particular rule to a specific address, and getting rid of unnecessary data. It helps you manage your campaigns more efficiently to ensure important messages do not go unanswered.
• Deliverability features – The platform offers additional deliverability features like send time optimization, email address validation, and inbox placement testing to optimize your deliverability.

Pricing

Mailgun has a free plan, but it only supports 100 emails per day. Paid packages start at $15/mo. It has no daily limit and supports up to 10,000 emails per month. You get two API keys and five inbound routes.

The Foundation plan costs $35/mo and gives you full access to RESTful email APIs and SMTP relay. This plan supports 5-day log retention, 50k email sends per month, 1,000 custom sending domains, and full access to inbound routing. 

Larger businesses and enterprises can use the $90/mo Scale plan to send 100k emails/month, get SAML SSO, 5,000 email validations, and dedicated IP pools.  

6. Amazon SES

You may want to consider the Amazon SES SMTP if you’re already in the Amazon ecosystem. It might be a good option if you’re using Amazon Web Services, for example. 

The Amazon SES, or Amazon Simple Email Service, allows developers to build email functionality into any application to send bulk emails. It’s very scalable and affordable. 

However, Amazon SES is also quite technical to use. It has a fairly steep learning curve, so it’s not ideal for smaller organizations or teams looking for a DIY option. This solution is ideal for bigger organizations with technical teams that can set up and manage the infrastructure.

Amazon SES provides dedicated IP addresses to help you manage your IP reputation. You’ll also get a dashboard showing insights into your sender reputation and email deliverability. 

While Amazon SES is highly scalable and affordable, it’s not ideal for teams that also want easy-to-use email marketing tools like an email builder and templates.

Source

Amazon SES features

• Virtual deliverability manager – The virtual deliverability manager provides recommendations on how to enhance deliverability and stop your emails from ending up in the junk folder. It can also implement some of the recommendations automatically.
• Mail manager – Amazon’s Mail Manager automates inbound email processing to help you manage incoming emails efficiently. For example, it supports automatic forwarding to send emails to specific servers within your organization. The manager also maintains the security of your email system.
• Sender identity management and security – Amazon SES supports several email security standards, including DKIM, DMARC, and SPF.
• Email receiving – the platform provides email receiving features like choosing what emails to accept and how to manage them once they’re accepted.

Pricing

Amazon SES is available on a pay-as-you-go model, so you’ll only pay for the number of emails you send and receive. But besides the emails sent and received, you will also be charged separately for other services like the mail manager, global endpoints, and Amazon Connect email.

Dedicated IPs are also sold as separate add-ons.

7. Mailtrap

Mailtrap offers developer-friendly SMTP services. For starters, they provide over 25 ready-to-use snippets to support quick and easy integrations with any application. 

The platform also validates all DNS records (DKIM, DMARC, and SPF) automatically. DKIM keys are rotated every month to maintain sender reputation and deliverability.

Mailtrap features

• Email testing – The platform offers a testing environment where you can capture SMTP traffic and analyze email content for spam score and HTML/CSS issues.
• Bulk email sending –Mailtrap provides a reliable RESTful SMTP email server to ensure optimal delivery of mass emails.
• Customizable templates – You’ll get both a visual drag-and-drop email editor as well as an HTML editor and email templates to design engaging emails.
• Detailed email analytics – Actionable analytics showing the performance of your campaigns and how you can improve.
• 30-day logs – You’ll have access to details on sent emails like event history, status, preview, and statistics for up to 30 days when you’re on the $750/mo enterprise plan. All other plans will still get logs, but for either 15, 5, or 3 days, depending on your chosen paid plan.

Pricing

Mailtrap provides just one plan that offers API, SMTP, and email marketing tools. The paid plans start at $15 per month. This supports 5,000 contacts and 10,000 email sends per month. 

You can get a dedicated IP and auto-warm IP by upgrading to the Business plan, which starts at $85 per month.

Mailtrap also provides a free SMTP service through their freemium package. However, this limits you to only 1,000 emails per month and 100 contacts. 

8. Mailchimp Transactional

Mailchimp is one of the oldest email marketing services. The platform provides SMTP and API services to support transactional emails. 

These features allow eCommerce businesses to process and send key emails like password resets, order confirmations, and other campaigns triggered by user actions. 

Mailchimp Transactional Email (formerly known as Mandrill) requires you to have the standard or higher monthly plan. That means you cannot pay for the SMTP or API alone. You must also have an email marketing plan. 

Once you have a paid plan, you’ll be able to access the Transactional Email feature, which is also sold as a separate add-on. This is one of the drawbacks of using Mailchimp’s SMTP and API; it tends to be quite expensive. That’s why some folks end up seeking other alternatives to Mailchimp.

Mailchimp Transactional Email features

• Automated transactional emails – Send transactional emails at scale with either the Mailchimp API or SMTP service.
• Process inbound emails – Mailchimp lets you receive, process, and parse inbound emails. They also provide webhooks to respond to email events like link clicks and opens.
• Data analytics – You’ll get actionable insights into your campaigns, like delivery rates and subscriber engagement.

Pricing

Mailchimp Transactional Email is priced in blocks. You buy a block where each block lets you send up to 25,000 emails. A block costs $20 per month when you buy between 1 and 20 blocks. Pricing drops to $18 per month for 21 to 40 blocks. 

As mentioned earlier, you’ll need a Standard or higher email marketing plan to access Mailchimp’s Transactional Email service. This plan costs $20/mo. 

If you want a dedicated IP address, you’ll have to buy it as an add-on at $29.95 per month.

9. Mailjet

Mailjet provides a powerful free SMTP relay service you can use to handle transactional emails. The free server lets you send 6,000 emails per month, which is pretty decent. However, there is a daily cap that lets you send only 200 emails per day. 

The platform provides documentation and tutorials to help you configure and use the SMTP service within minutes. They also have servers all around the world and support auto-scaling mechanisms to help you send emails at scale easily as your needs grow.

Mailjet features

• Easy domain authentication – Set up your SPF, DMARC, and DKIM records to start sending emails and ensure inbox placement. The company also provides a deliverability team to help manage your campaigns.
• Real-time dashboard – Mailjet provides an analytics dashboard that shares real-time data on your campaign’s performance. You’ll have data on opens, clicks, unsubscribes, and bounces. You can also use webhooks to get notifications based on specific rules or triggers.
• Advanced personalization – The platform supports dynamic content, which you can use to personalize your email campaigns.

Pricing 

Mailjet’s paid plans start at $17 per month. This plan removes the 200 emails per day limit. You can send a total of 15,000 emails per month. 

The premium plan costs $27 per month. You’re still limited to 15,000 emails/mo, but you get additional features like dynamic content, marketing automations, and advanced analytics. The plan also supports A/B testing, and you get one dedicated IP address if you choose the 100k emails package. 

You can also get a customized package at custom pricing if you have specific deliverability needs and want advanced capabilities.

Beyond SMTP: Complete marketing solutions with GetResponse

GetResponse Max offers more than just reliable SMTP services. Access our complete suite of marketing tools including AI-powered product recommendations, advanced segmentation, automation workflows, and a webinar platform—all designed to help you grow your business while maintaining excellent email deliverability.

Factors to consider when choosing an SMTP email service

There are plenty of SMTP email providers on the market. Most of them provide similar services except for a few differences here and there, like the number of emails you can send on the free plan and access to dedicated IP addresses. Pricing packages also vary.

So, use the following criteria to vet SMTP email service providers.  

One of the biggest reasons behind paying for an SMTP email provider is to offload the burden of dealing with the complex infrastructure. That’s why you must be careful and pick a provider whose platform is actually easy to use. 

They should provide all the resources needed to get up and running. That includes API documentation, an educational onboarding process, great learning resources, and a responsive support team in case you need expert help.

Email deliverability determines the percentage of emails reaching your target recipients’ email inboxes. The best SMTP service providers guarantee a high email deliverability rate to ensure your emails don’t end up in the junk or spam folder.

Email deliverability is particularly important when you’re sending high-volume emails. It ensures that every email hits the user’s inbox and that your email messages are not incorrectly marked as spam, which would hurt your sender reputation.  

Even the best platforms run into issues at some point. When that happens, you’ll want to know that the customer support team will be responsive and eager to help.

Therefore, choose an SMTP provider with excellent customer support. First, they must provide several support channels. Ideally, you’ll want live chat, email, and a direct number if possible. 

Next, the team must be responsive. You don’t want to be stranded for several days waiting for a reply from the support team. These can hurt your business’s bottom line, especially if you’re relying on email for crucial communications like transactional emails. 

Go through the customer reviews on independent platforms like G2 and Capterra. Look at what other users of that SMTP provider have to say regarding the customer service.

Pricing is another critical factor you should analyze carefully. Consider both your current and future needs. Then, pick an email service provider that can meet those needs at a reasonable price. 

Most SMTP services provide tiered pricing. The price changes based on the number of emails you need to send and additional email features or tools. 

For example, most will charge for dedicated IP addresses as a separate add-on. 

Make sure your provider has transparent pricing to avoid surprise charges down the road. Also, most vendors tend to offer promotional prices for first-time buyers. Look at the renewal rate to make sure it’s still within your budget. 

• Data analytics capabilities

You need accurate data to make informed decisions regarding your email campaigns. So, make sure your SMTP platform shares insightful data on your email marketing campaigns. 

Also, remember that some platforms may charge you extra to access extensive data analytics. Factor this into your budget if you’ll need access to that data. 

What security measures has the SMTP relay server provider taken to ensure emails are secure and adhere to industry regulations? 

At the very least, the provider should support standard email authentication protocols like DKIM, DMARC, and SPF. Additionally, inquire if the provider has multiple servers for redundant purposes to ensure optimal uptimes. 

In closing

SMTP email services are necessary for any organization or business that sends mass emails. Think of an ecommerce business that must send password reset, order confirmation, shipping details, and other similar emails.

A great SMTP provider ensures all these emails are sent on time and are placed in the recipient’s inbox. Beyond that, the best providers, like GetResponse, support automations so you can handle personalized mass campaigns and provide intuitive email editors to design engaging emails with ease. 

Get in touch with our team to see how GetResponse can support your SMTP sending needs.

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