Most people file both under email marketing, yet they start from opposite ends. Twilio SendGrid is built around an email API and SMTP relay for mail your app sends, with campaign tools added; Mailchimp, owned by Intuit, presents itself as a full marketing platform that also lists a Transactional API. Developers sending receipts lean SendGrid; marketers running campaigns lean Mailchimp.
Both names turn up whenever a business sets up email, so it's easy to treat them as two versions of the same thing. They aren't. One grew from the code side, where an app sends a password reset the moment someone asks for it. The other grew from the marketing side, where a person designs a campaign and schedules it for a list. Each now reaches into the other's territory, which is exactly why it helps to sort your email by job before you compare features.
Sort your email by job in five steps
- List every email your business sends in a normal month, from receipts and password resets to newsletters and offers.
- Mark each one as triggered by something a person did in your app or shop, or written and scheduled by your team.
- Note who owns each kind: a developer who works in code, or a marketer who works in an editor.
- Write down what each kind needs most: instant delivery and a clean sending reputation, or design, audiences and automation.
- Match the bigger pile to the service built for it, and check whether the other one can cover the smaller pile.
Most small businesses find one pile is far bigger than the other. An online shop with a busy checkout sends far more triggered mail than campaigns; a coach or consultant sends almost nothing but newsletters. The size of each pile decides where you start.
Receipts and campaigns are separate jobs
Triggered email, often called transactional email, is sent by software when something happens: an order, a sign up, a forgotten password. Nobody writes each one by hand. It has to arrive quickly, it usually goes to one person at a time, and it's built from a template that code fills in. The people who set it up are developers, and they care about how the service connects to their app, whether through an API or an SMTP relay, and about the sending reputation of the addresses and domains it goes out from.
Campaign email is written by people for groups of people. A newsletter, a launch, a series that runs after someone joins your list. The people running it care about the editor, the audience, the automation that sends the next message when someone clicks, and the landing page the email points to. Speed matters less than timing and relevance.
Plenty of businesses need both, and that's where the overlap between these two services matters. A platform built for one job can usually do some of the other, but the tools, the team that runs it and the way it's set up will still reflect where it started.
A quick way to tell the two apart is to ask what happens if the email arrives an hour late. A late newsletter is a small annoyance. A late password reset or order confirmation means a customer stuck at a login screen or ringing to ask whether their order went through. If lateness would break something, the message belongs in the triggered pile, and the service you send it through should be judged on speed and reliability first.
Where SendGrid begins
SendGrid is now branded Twilio SendGrid and sits inside Twilio's platform. Its Email API sends email through RESTful APIs or SMTP relay, which is the developer's route. It lists dedicated IPs and custom domains for deliverability, an SMTP service, email validation and a dynamic templates builder, which together cover what an app needs to send triggered mail at volume. It also pitches email marketing automation, so a team can run campaigns from the same account. Its own headline claim is industry leading deliverability; read that as the vendor's claim and test it with your own mail.
Where Mailchimp begins
Mailchimp describes itself as a full marketing platform, covering email, SMS, automation, landing pages and more. It includes automation flows based on customer behaviour, so a purchase or a click can start a sequence, and it includes landing pages, so a campaign and the page it points to live in one place. For developers, its menu lists a Transactional API and transactional email, which means triggered mail is on offer too.
Owners, names and overlapping features
Two ownership facts change how these products are described, and they're on the vendors' own pages. SendGrid is now Twilio SendGrid, built around an email API and SMTP relay inside Twilio's wider platform. Mailchimp says it was acquired by Intuit, and its terms say it's part of the Intuit group of companies with Intuit Inc. as parent. If you remember either from years ago, the name on the login page may have changed.
The other thing to see clearly is the overlap. SendGrid pitches marketing campaigns; Mailchimp lists a Transactional API. So the question isn't whether each one can do the other's job at all, it's which job each is built around and which team will open it every day.
SendGrid and Mailchimp in brief
Listed alphabetically and in no particular order. Each line is built from what the vendor says about its own service.
| Tool | What kind of service | Who it suits |
|---|---|---|
| Mailchimp | Email marketing platform | Marketers running campaigns, automation and landing pages |
| Twilio SendGrid | Email API and marketing | Developers sending app email by API or SMTP |
Mailchimp
Best for: Marketers wanting email, SMS, automation flows and landing pages together; vendor claim: a full marketing platform, with a Transactional API for developers.
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Twilio SendGrid
Best for: Developers sending email from an app through RESTful APIs or SMTP relay, with dedicated IPs and campaign tools; vendor claim: industry leading deliverability.
Developers, marketers and the mixed team
If a developer owns your email and most of what you send is triggered by your app, Twilio SendGrid's API, SMTP relay, dedicated IPs and template builder are designed for that work. If a marketer owns your email and most of what you send is campaigns, automation and landing pages, Mailchimp's platform is designed around that. If you send plenty of both, decide which team will run the account day to day, and check that the other side's needs are covered before you commit.
For more options, see my list of SendGrid alternatives, my comparison of SendGrid vs Mailgun, and my answer to is Mailchimp free if you're weighing the trial.
Do you make email sending or marketing software? Tool makers can ask to be considered for a featured place on this list.
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Frequently asked questions
Is SendGrid the same as Twilio SendGrid?
Yes. SendGrid is branded Twilio SendGrid and sits inside Twilio's platform.
Who owns Mailchimp?
Mailchimp says it was acquired by Intuit, and its terms say it's part of the Intuit group of companies with Intuit Inc. as parent.
Can Mailchimp send transactional email?
Mailchimp's menu lists a Transactional API and transactional email under its developer section. Check its documentation for how it's set up.
Can SendGrid run marketing campaigns?
SendGrid pitches email marketing automation and marketing campaigns alongside its Email API, so a team can run both from Twilio SendGrid.
Does Mailchimp offer a free plan?
Mailchimp's own site points to a free trial rather than a free plan. Plans and limits change often, so check the vendor's site before you sign up.
Does SendGrid support SMTP?
Yes. SendGrid says its Email API sends through RESTful APIs or SMTP relay, and it lists an SMTP service.
