Mailgun vs. SendGrid: Which is the Best Transactional Email Service?

As long as email has existed, email marketing has been one of the most effective marketing channels.

Considering its impressive ROI of $42 for every $1 spent, even after over 50 years, email marketing still has the highest return on investment out of any marketing method.

Transactional emails aren’t sent with the intent of marketing, but they can still be included in the field of “email marketing”. Companies can put marketing content in those transactional emails to upsell or cross-sell their customers, raise brand awareness, get them to share their experience with the brand, and much more.

It’s no surprise that there are a plethora of transactional email services to choose from today, as transactional emails are arguably the most important emails a company needs to send to customers who take action, like making an account or a purchase.

Two of the most prominent names in the transactional email service space are Mailgun and SendGrid; both transactional email services with storied histories in the email marketing space.

Now, Mailgun and SendGrid may fall into the same category of transactional email services, but that doesn’t mean they’re interchangeable. Each transactional email service has its own strengths and weaknesses, and that can’t be ignored.

If you’re looking to choose a reliable transactional email service, doing so without information on both services may lead you to make a bad choice. Not that either service is bad, but one might not fit your needs as well as the other.

To make sure you’re properly informed, I’ll walk you through the main differences between Mailgun and SendGrid, including their target audience and transactional email features so you can find the transactional email service that’s right for you.

Without further ado, this is Mailgun vs. SendGrid.

What is Mailgun?

Mailgun is a transactional email service geared for developers – as they say on their website, they build everything “API-first”, meaning that Mailgun provides their transactional email tools with the intent of their customers building great apps and email programs with them as opposed to just using Mailgun’s platform natively.

Trusted by major names like Microsoft, Wikipedia, the NHL, American Express, and more, Mailgun clearly has all the features and reliability these companies could ask for.

On top of that, over 150,000 businesses trust Mailgun for their transactional email needs.

Mailgun makes sure every statistic in your transactional emails is optimized: send time, deliverability, open rates, and more.

Mailgun offers a month-long free trial with 5,000 emails included. If you exceed that 5,000 email limit, you’ll pay $1.00 per 1,000 emails you need over that limit.

As for their paid plans, they start at $35/mo with 50,000 emails per month included, including inbound email routing, email address verification access, 24/7 ticket support, and more. The plans scale their pricing based on how many transactional emails you want to send per month, from 10,000 monthly emails to over 2.5 million monthly emails.

What is SendGrid?

A Twilio company, SendGrid is a transactional email service with a more general focus. They do include developers in their target audience, but they also include start-ups, marketers, enterprises, and e-commerce use cases as well.

SendGrid offers users more standard email marketing features, like email automation, A/B testing, email design, and more, but here I’ll be focusing on their transactional email features.

Some of the key features of SendGrid are its SMTP service, so users never have to worry about email servers; email infrastructure, so users never have to encounter outages; email validation, so your messages are being delivered to real contacts; and much more.

On top of that, SendGrid has recently introduced its Deliverability Insights, which aims to give users optimized insights into their email analytics through an intuitive user interface, displaying primary statistics like processed mail, delivered mail, failed deliveries, opened mail, and more.

Unlike Mailgun, SendGrid has a free plan where you can send up to 100 emails per day forever. This includes 1 teammate permission, APIs, SendGrid’s SMTP relay, a dynamic template editor, delivery optimization tools, and much more. Of course, as this is a free plan, there are some features missing like no email validation, no dedicated IPs, no SSO, and more.

As for their paid plans, SendGrid starts at $19.95/mo for up to 50,000 emails per month and scales up to over 1.5 million monthly emails.

Mailgun vs. SendGrid at a glance

Below is a comparison table that outlines the main differences between Mailgun and SendGrid. I’ve written a more detailed comparison below if you want to skip the table, but here is an at-a-glance comparison:

Ease of UseGeared towards developers; may be slightly unfriendly to less tech-savvy usersProvides a checklist for new users to get started, but not intuitive for new email marketers
Transactional Email FeaturesHIPAA & GDPR compliant RESTful email API, in-depth email analytics, send time & deliverability optimization featuresStandard email marketing features plus transactional deliverability insights, email validation, SendGrid SMTP service
Integrations64 integrations including WordPress, Asana, Monday, and more; custom integrations can be made121 partners including Google Cloud, Bluecore, SendCloud, and more
Customer SupportHelp center with article guides for users to solve problems, Mailgun real-time status report, plus live chat & email supportIncident report log, knowledge center, extensive API documentation
Pricing30-day free trial available; paid plans start at $35/moFree version available; paid plans start at $19.95/mo

Mailgun is built for developers

As I mentioned earlier, Mailgun is built with the intention of their APIs being used in other peoples’ transactional email apps so they can get their emails started as fast as possible, and with extensive documentation.

Mailgun’s email API is covered extensively in its documentation, which includes popular programming languages like Python, Ruby, Java, C#, and more to fit any development team’s needs.

To protect your sender reputation, Mailgun allows its users to send with SPF (Sender Policy Framework; to prevent phishing), DKIM (DomainKeys Identified Mail; to verify the sender), and DMARC (Domain-Based Message Authentication, Reporting, and Conformance; to protect your domain from hacker attacks) security protocols.

The more security protocols you send your emails with and the more you authenticate, the higher your email deliverability will be.

Now, on the topic of deliverability and analytics…

As you can see above, Mailgun provides its users with an in-depth analytics panel including statistics on how many emails were delivered, opened, clicked, and failed. On top of that, users have the ability to understand the email life cycle through log retention on all of your messages to get a better understanding of what is impacting your email performance and deliverability.

Pivoting to another developer-centric feature, Mailgun helps users optimize incoming emails and parse out unnecessary data through Inbound Routes, then converting those inbound emails to UTF-8 JSON for easy reading.

Email parsing is incredibly important for any business, as unnecessary data flooding in can mean that important messages are being missed. This can result in unintentional poor customer service and wasted time for a company, both of which Mailgun is great at handling.

Overall, Mailgun’s developer-centric feature set is perfect for individuals or companies who want to optimize their transactional email processes and/or create their own applications with the host of Mailgun APIs available for users.

SendGrid is a general powerhouse

Again, SendGrid is much more generally applicable than Mailgun, but they also compete in the transactional email space.

One of the most helpful features SendGrid offers is its email testing capabilities. When you’re creating an email from scratch or using a template, you can never guarantee that the email will look the same in someone’s inbox as it does when you send it out.

This could be due to different browsers or devices, but the end result is that the HTML rendering might not end up looking how you want it to.

With SendGrid’s email testing, you can get comprehensive data on how your created emails will perform against spam filters and across devices, plus validating any links you’ve included in those emails.

Another major transactional email feature that SendGrid offers is its email address validation API, so users can maximize their deliverability and avoid funnel leaks.

SendGrid avoids spammer-affiliated transactional email tactics to maintain a good sender reputation, one of which is the broken SMTP handshake. This is when an API attempts to validate an email address by connecting to mailbox providers until they receive a response then immediately breaking the connection.

As previously mentioned, this is a tactic that spammers tend to use and can negatively impact your sender reputation and SendGrid makes sure to avoid it along with many other spammer-affiliated tactics.

Overall, SendGrid is hyper-fixated on deliverability and sender reputation as transactional emails go, and they make sure your emails get where they need to go without tarnishing your sender reputation.

Conclusion: Mailgun vs. SendGrid?

When comparing Mailgun avs. SendGrid, it’s very clear that they are two transactional email platforms with two different audiences.

Mailgun’s interface and features suit users who want to create their own apps using all kinds of transactional email APIs, and SendGrid’s features, while they do also cater to developers, are more generally targeted at people who just want to use SendGrid on SendGrid’s platform.

Ultimately, the choice between Mailgun and SendGrid depends on your specific needs.

I won’t leave you hanging there, though; as I’ve stated several times in this comparison, the audience for each platform is pretty clear.

If you’re a developer yourself or have a team of developers as a part of your business, then Mailgun’s APIs will suit you or your team better.

If you’re someone with not only a need for transactional emails but overall email marketing features, then SendGrid will suit you better.