Email Fight!

Which email service will win? I am pitting several email services against each other. Twilio/sendgrid, Mailgun, and smtp2go are the current fighters, while SparkPost knocked themselves out!

This website sends out a small number of emails every day and I use an email service provider to do that. Quite a few email service providers have a free tier in their pricing. These free tiers are always limited to a low number of emails every month. I thought to myself, What if I did a round robin amongst several different email senders? This would be a learning experience and show any problems (Some email senders may have spammy practices, some may have difficult APIs, etc). This will be a great way to identify and qualify the services.

Yes, this means more development work for me, but I was able to set up most of these services in under an hour each, and if a future client of mine already has email services through one of these providers, I’m already set up to start sending for them.

Of course, I might as well report on the set-up process for each as well. As issues pop up or service agreements are ended, I’ll update this post. And yes, they do end. They get you with a “100 emails per month free forever!” …but eventually they stop offering that. Mailgun was offering a free-forever tier up until some time in 2021.

Caveats: I’m looking for easy-to-use, high-deliverability free tiers that support API calls. I am not testing SMTP services.

Because I enjoy complaining, and because these have the most information, I’m listing the disqualifications first!

mailersend 👎
Updated Feb 26, 2022

mailersend has a free tier but they do not use the word “forever.”

Initial setup was the most difficult. You have to describe your company to their satisfaction. Apparently a human needs to read it and approve you. This struck me as odd at first, but I’m sure it helps keep spammers off their networks which is ultimately a plus. If a sketchy user is allowed to send spam emails from their servers, it makes all the emails from their servers look more suspicious, which would include mine. They rejected my initial company/usage description after about 12 hours, during which time they said I’d be able to send test emails to my one domain, which I was not able to accomplish. They approved my revised company/usage description in a couple hours on a Saturday morning, so I was excited to run my tests again. However, all my requests are rejected as 422 Unprocessable Content - meaning the data is missing. I even tried sending the example data packet from their documentation and got the same error.

I put in a support request on the same Saturday, which is their only hope of joining my round-robin. UPDATE: The first response to my support request asked for information that was already in the original support request (and was visible in the email chain). The second response asked if the sending email address was on the verfied domain in their system. Maybe a neophyte would make that mistake, but I set up five API-consuming class files this morning. The email in question is in the original support request, and they should be able to easily look up my verified sending domain.

That’s two hours of my life I will never get back. I hope this helps someone else make a decision about mailersend.

Updated Feb 2022
The postmark free trial is a bit hard to locate, and it claims to allow “100 test emails per month.” I was suspicious of what a “test email” was, and according to their own documentation, “Postmark lets you send test emails that won’t actually get delivered to the recipient. This method is typically used to verify that your data is valid.” They are disqualified and will not be competing. If they update their offer, I hope they let me know.
In the Fightin’ Pit
Updated Feb 2022

smtp2go offers a free tier but does not use the word “forever.” smtp2go was the easiest of the five services I set up today. They supply 3 CNAMEs to add to your DNS that cover DKIM and bounce/tracking, which is good.

The free tier they offered me in Feb 2022 is 1000 free emails per month, but does not include the word “forever.”

smtp2go is in the fight! Stay tuned for updates!

UPDATE December 8, 2022: Over the last 8 months or so, I have sent a little over 550 emails for free through smtp2go. Two requests were met with a 408 Request Time-out, but otherwise this service has been fine.

Updated Feb 2022

Mailgun stopped offering a free-tier. Now their smallest offer is a free-for-three-months plan. They are in my battle royale because I originally signed up when they did offer a free tier, and they are not charging me anything at this time. I don’t recall any difficulties with their set-up, however their free plan only allows sending to yourself at one domain. So I'll use them to alert myself.

Mailgun is in the fight, despite this handicap! Stay tuned for updates!

UPDATE December 8, 2022: Over the last 8 months or so, I have sent a little over 400 emails for free through Mailgun. One request was met with a 502 Bad Gateway, but otherwise this service has been fine.

Twilio Sendgrid

I’ve actually had a lot of experience with sendgrid as one of their clients at my day job. Setting up from scratch was easy, and they provide the most comprehensive CNAMES to add to your DNS. This was the only service I set up that worked on the first try, if that is worth anything.

The free tier they offered me in Feb 2022 is 100 free emails per day forever.

Twilio Sendgrid is in the fight! Stay tuned for updates!

UPDATE December 8, 2022: Over the last 8 months or so, I have sent a little over 500 emails for free through Twilio Sendgrid. All requests have been accepted.

Knocked Out
SparkPost 👎
Updated Sept 2022

For some reason SparkPost does not have a link in their navigation to their pricing page. This almost ruined it for me. I’m picky.

Anyway, account set-up with SparkPost and first email sent was of average difficulty. They supply DNS records to add for DKIM and a CNAME for sending/bounce domains, which is good. Their setup UI/flow made me think I needed to set up a subdomain for their service, but it is now interfering. I will need to adjust my account with them before they can be in the round-robin.

The free tier SparkPost offered me in Feb 2022 is 100 free emails per day, but does not include the word “forever.” Their pricing page promotions do not tell you that there is a second cap on usage: 500 emails per month. If you sent 99 emails per day, it would only be free for five days. Then they charge overage fees. Also, their daily cap is a rolling 24-hour period, not a count of how many emails were sent since midnight.

Nonetheless, they are in the pit. Stay tuned for updates!


After a little more than six months, my requests started getting denied with 403s. Email sendings were failing. I went to log in to their website, and my login and password were not recognized. I did a password reset, which was accepted, but after logging in, I got the message that my free Account No Longer Exists.

Over those six months I sent around 300 emails. For free. But then, without any notice, the account was "deleted."

Thanks for playing, SparkPost, but you were the first contender to be knocked out - and you did it to yourself. I cannot recommend SparkPost.

Getting Ready
Still getting around to putting this service in the fight.
Updated Feb 2022
The sendin blue free tier sends emails with sendinblue branding, so I have not added them to the roster yet.
Updated Feb 2022
The mailjet free tier sends emails with mailjet branding, so I have not added them to list yet.
Amazon Simple Email Service
Amazon Simple Email Service offers 62,000 emails per month but only if they originate from an app hosted in Amazon Web Services EC2/Lambda, with some other fees, so they won’t be a part of this experiment.
As of Feb, 2022, SocketLabs does not offer a free tier.
Elastic Email
Elastic Email does not offer a free tier, as of Feb 2022.
netcore does not show any pricing structure (even googled for it) and it looks like they have outgrown the need to offer a free tier.

Who will win this competition? Someday I hope to have so many clients that I need to upgrade my service plan with one of these companies. May the best service win!

If there is a service you wish was fighting in this pit, please let me know about them.