10 Best SMTP Services For Email Marketing 2021 [Free & Paid]

By |

Email marketing is one of the best mediums of marketing. It is considered among the oldest methods of online marketing but still effective.

Emails are an important medium of communication between a website and users. An SMTP service provider allows website owners to send emails from the website to your users.

WordPress uses PHP to send emails by default. SMTP servers are made with the purpose to send emails properly.

If you are looking for the best SMTP services then you are in the right place. In this article, I am going to share some of the best SMTP service providers with high email deliverability.

So let’s get started.

List of Best SMTP Services For Email Marketing

There are many SMTP service providers and one can easily get confused. Each of them has different features, pricing, ease of use, etc.

You would also get some free as well as paid service providers. Here is a list of some of the best SMTP service providers that offer best in class features and high deliverability.

SMTP Service Provider

Free Plan

Official Link

1. Sendinblue


2. WP Mail SMTP By WPForms


3. Mailgun


4. Mailjet


5. SendPulse


6. SendGrid


7. Amazon SES


8. SocketLabs


9. Postmark


10. Pepipost


1. Sendinblue [Offers Free Plan]

best SMTP service

Sendinblue is another popular SMTP service provider that comes with awesome features. For trigger-based and transactional emails this tool comes in handy. Its automation workflow design allows users to build campaigns triggered by various actions like clicks, opens, and even webpage visits.

To boost the performance you can automate segmentation and marketing messages. It works with WordPress and other third-party services like Google Analytics, OptinMonster, Salesforce, and many more.

Turn your website visitors into paying customers through landing pages. It also provides SMS marketing services.


Sendinblue has a free plan that allows you to send 300 emails per day. The first paid plan named Lite allows you to send up to 100,000 emails with no daily sending limit. This plan costs $25 per month.

2. WP Mail SMTP by WPForms

WP Mail SMTP best smtp service

WP Mail SMTP by WPForms is a free WordPress plugin for SMTP. It is a very popular plugin used by over 1 million websites to send their emails reliably.

This plugin includes many different SMTP setup options like Mailgun SMTP, SendGrid SMTP, Gmail SMTP, etc. It works with all the popular email marketing services.

One can setup WP Mail SMTP easily without the need for a developer. It uses proper SMTP configuration setups that help you to increase email deliverability by using authentication.

It’s available as a free SMTP plugin in the WordPress repository. You can upgrade to the pro version anytime to get access to more features.

3. Mailgun

Mailgun best smtp service

Mailgun is a popular SMTP service provider for software developers and businesses. Currently, it is used by over 225,000+ businesses worldwide.

This tool has a real-time email validation feature to check it before sending it. Mailgun has also a bulk email validation tool. It makes it super easy to clean out inactive/invalid emails from your email list. You can upload CSV files as well.

It has a feature called Inbox Placement, that can predict email deliverability issues. This allows you to resolve issues before sending out your emails. This way, you can increase email engagement ratio and ROI.

This a professional tool for developers and may lack for beginners.


Mailgun comes with various plans for different requirements. Currently, they don’t have a free plan for users. The first plan Flex allows users to send 5,000 free emails per month for 3 months. Then you have to pay as per your sending emails. The next plan is called Foundation and costs $35 per month.

4. Mailjet

Mailjet best smtp service

Mailjet is another widely used SMTP service. It contains all the powerful features you ever needed to build a strong email marketing campaign.

Mailjet’s robust delivery infrastructure and advanced API route billions of emails to the recipient’s inbox every month. Its free SMTP server integration is easy and beginner won’t face any difficulty.

It supports a variety of ports with the SMTP relay. You can choose the most suitable port for you that depending on your email client or ISP.

This service comes with a real-time dashboard that makes it easier for you to browse various data. You can also set filters and measure key performance indicators like open rates, link clicks, bounces, and unsubscribes, and more.


Mailjet has a free plan that lets you send 200 emails per day and 6,000 emails per month. The first paid plan named Basic costs $9.65 per month. With this plan, you can send 30,000 emails per month.

5. SendPulse

SendPulse best smtp service

SendPulse is a reliable SMTP service provider best for all types of emails. You can integrate this into your CMS (WordPress), CRM, or other system and then send unlimited e-mails to your customers from your own online system.

You can use a dedicated IP address to increase email sender reputation and avoid blacklisting or emails going to the spam folder of your IP due to someone else’s actions.

This service comes with detailed analytics where you can see the number of conversions made, open rate, links clicked, and many other details. Their SMTP servers send emails using a secure SSL connection so you can get maximum security.


SendPulse comes with a free plan that allows you to send 12,000 emails per month. The Pro plan costs $59.88 per month with a dedicated IP address and allows you to send 100,000 emails.

6. SendGrid

SendGrid best smtp service

SendGrid is a very popular cloud-based email platform that delivers emails to over 28 billion customers. It handles operations of internet-based companies such as Spotify, Linkedin, Uber, Pinterest, Airbnb, Pandora, Hubspot, and FourSquare, as well as traditional companies such as Intuit, Taco Bell, Walmart, and Costco.

SendGrid has a highly qualified team of experts who are focused on email deliverability and compliance. Additionally, this tool provides stats for open rate reporting, link tracking, and CAN-SPAM compliance.

It is user-friendly and you can easily integrate with the email API and massive amount of send emails that will reach the recipient’s inbox. Use its real-time API to detect and remove invalid email addresses. It uses machine learning to validate all emails.


SendGrid plans are categories into 2 categories. Email API plans and Marketing Campaigns Plans. Both plans come with a free plan that allows you to send emails without any cost. The paid plan starts from $15 per month.

7. Amazon SES

Amazon SES best smtp service

Amazon Simple Email Service (SES) scalable email service that allows developers to send various mail from within any application. It is a cloud-based service from Amazon Web Services.

Amazon SES has been designed to send transactional emails, eCommerce emails, marketing emails, or any other type of quality content to their subscribers.

This service can send 3,000 emails per second which is a very humongous number. You would get a detailed analytics dashboard to get performance insights and to maximize your deliverability.

By default, Amazon SES allows users to send emails from shared IP addresses. If you want to manage your own IP reputation then use the dedicated IP pools feature inside Amazon SES to create pools of those IP addresses.


Amazon Simple Email Service (SES) is working on a pay-as-you-go service-based model. You will pay based on the volume of emails you sent and received. There are no subscriptions and upfront charges.

For example, if you send 250,000 emails per month then it will cost $25. It allows you to receive 1000 free emails per month.

8. SocketLabs

SocketLabs best smtp service

SocketLabs is another free SMTP service provider that allows developers to deliver timely bulk emails to their recipient’s inbox. It comes with an advanced email delivery service and APIs that provide fast and powerful integration.

This service comes with high deliverability that ensures all your outbound emails avoid any spam filter and land on inbox.

SocketLabs comes with easy and fast integration. Simply connect your SMTP credentials to your website or application and start sending emails for free.

It has a web-based statistical reporting system that gives you real-time insight into your delivery status. You can analyze the performance using this.


SocketLabs comes with a free plan that allows you to send 40,000 emails for the first month and then 2,000 emails each month. The first paid plan named Basic and costs $39.95 per month.

9. Postmark

PostMark best smtp service

Postmark is another easy to use SMTP service provider for websites and applications. It promised to offer lightning-fast email delivery. Postmark has SMTP servers located around the world to ensure superfast email delivery.

Postmark is specialized in transactional emails. It supports TLS to secure data inside an email sent between your application and their servers.

This service comes with developer-friendly documentation and covers advanced features like tags and custom metadata.

Postmark stores the full conversation and message event history for every email send through it for 45 days. It comes with a detailed analytics dashboard that can track bounce rate, delivery status, open rate, link click, etc.


Their pricing depends on the number of emails you send. The base plan starts from $10 where you can send 10,000 emails. There is also a free trial to get started.

10. Pepipost

PepiPost best smtp service

Pepipost is another popular and fast SMTP email delivery service provider. According to the official website, they are delivering 8 billion emails per month for over 50,000 customers.

Its SMTP servers are located globally at multiple locations. This avoids network latency and ensures super fast delivery. Their service uses an AI-powered engine to analyze the recipient’s behaviors and deliver emails at that time.

Security is a priority for Pepipost. By default, Pepipost comes with opportunistic TLS for all outbound emails.  


Pepipost comes with variable pricing based on the number of emails you send. There is also a free plan that lets you send 30,000 emails free for the first 30 days and then 100 per day. If you need to send 150,000 emails per month then the cost would be $17.5 per month.

What is SMTP?

smtp protocol best smtp service
Image Source: Educba.com

SMTP stands for Simple Mail Transfer Protocol is an industry-standard for sending electronic emails using the internet. It uses high-end authentication that increases the chances of emails delivered in users’ inbox and doesn’t end up in the junk mail folder.

It is a program used for sending emails to another computer/server users based on e-mail addresses. The main purpose of SMTP is used to set up different communication rules between servers.

The servers have built-in programs to identify themselves and perform what kind of communication they are trying to execute. They also have an identification system for handling errors such as the wrong email address. For example, if you try to send an email address with a wrong address, then the server reply with an error message of some kind.

Also Read:How To Gmail With Custom Email Address [Send & Receive Emails]

Why Do You Need an SMTP Services?

WordPress based websites rely on email for various things like new account registration, password recovery, new post publish notification, etc.

For an eCommerce website, emails are very important. You are selling things and dealing with people’s money. You need to make sure that users should get emails with order invoices, delivery details, etc.

WordPress default email sending system uses PHP. But it is a serious limitation. A lot of shared hosting providers don’t want to configure PHP properly, or they’ve disabled it completely to avoid abuse. The overall system can be misused and it does not require authentication. One can easily use this to send spam emails.

WordPress emails often landed on the spam folder of the recipient because most spam filters will verify sender email and many additional details.

The only way to avoid such problems is by using a robust SMTP server to send WordPress emails. SMTP service providers use high-end servers to ensure that your emails are properly delivered to the recipient’s inbox.

To do successful email marketing, you need to pick the best and high quality SMTP service provider. A lot of SMTP companies offer free SMTP plans. These are good enough for most websites. If you want more then switch to paid plans anytime. It completely depends on your website requirements.

7 Things To Look For In An SMTP Service Provider

When you are out for the best SMTP plugin then make sure to check the below things.

To be honest, SMTP is not for absolute beginners. You need to have some technical skills to set up and use email services.

Some WordPress plugins allow you to set up this service easily. But some of the top services also demands technical setups and maybe developers.

Emails delivery rates are important than anything else. If you send an email and it not rich to the recipient’s inbox then what would you expect?

Popular email clients like Gmail, Yahoo, Zoho, and Office 365 are in a constant uphill battle with email spammers. If the proper authentication isn’t equipped in the service, then emails either go in the SPAM folder or in the worst case, don’t get delivered at all.

Almost all the email service providers clam to provide the highest delivery rate. But you need to check what they are actually offering.

How many times have you see a mail bounce and don’t delivered because the recipient’s email address was invalid?

Businesses lose thousands of dollars every year just because of bounced emails. Each email that bounces has a serious impact on your engagement metrics and sender IP reputation drop. A low IP reputation means more deliverability problems and email lands in the spam folder.

This is why your SMTP service provider should have an email validation feature. It will let you know the wrong email addresses before sending a mail. When choosing an SMTP service provider check this feature.

Many service providers come with a free trial or plan to test their features. In addition to that, they also have various plans.

You need to check whether your service provider has enough features and a number of emails in that plan. Some service providers like Amazon SES offer pay as you use the medium. This is also good because you don’t have to take a huge plan and use a chunk of it.

Your website or application should compatible with the service you are going to choose. Basically, they provide API to connect your application with their email servers.

Your SMTP service provider might have to put so much effort to deliver emails on the backend. But on the frontend, you need to have an analytics dashboard.

This is where you can check email delivery rate, bounce rate, open rate, link click, etc.

Customer support is one of the vital aspects of any online service. You need to make sure that the SMTP service provider should provide enough support.


So these are some of the best SMTP services for email marketing. Email is on the rise as one of the most valuable communication media on the internet today.

For best results, you need to have a reliable SMTP services with all the necessary features.

Bibhu Prasad Bal is a content writer at BloggingForge and a tech-savvy guy. In spare time you will find him watching Ancient Aliens and exploring the web. Contact - bibhu@bloggingforge.com

1 thought on “10 Best SMTP Services For Email Marketing 2021 [Free & Paid]”

Leave a Comment