Email Service Providers
Email service providers are the platforms that store an audience and send it email at scale: list management, campaign editors, automation, and the sending infrastructure underneath.
The ESP is the oldest product in the GTM stack and still the workhorse: newsletters, product announcements, and broadcast campaigns all ride on it. The current generation competes on editor quality, audience monetization, developer experience, and deliverability reputation, with focused independent vendors repeatedly out-shipping the legacy suites.
beehiiv
MomentumThe newsletter platform where monetization is the product
EmailOctopus
Email marketing stripped to the essentials, priced like it
Kit
The creator-economy ESP, with a network and an app store attached
Loops
Marketing, lifecycle, and transactional email in one tool, built for SaaS
MailerLite
Full feature set on every paid plan; you only pay for list size and volume
Brevo
The European ESP that bills by emails sent, not by contacts stored
Klaviyo
The ecommerce ESP that bills by active profile and reports in revenue
Mailchimp
Category LeaderThe default small-business ESP, now an Intuit product with an Intuit price
ActiveCampaign
The deepest automation builder a small business can actually buy
Omnisend
Ecommerce email and SMS for stores that want Klaviyo's flows without Klaviyo's invoice
Substack
Free to send, 10 percent of everything you earn, and a social network attached
Buttondown
A small, honest newsletter tool that bills only for people still reading
Ghost
Open-source publishing with newsletters, memberships, and 0 percent taken
Resend
InnovationThe transactional email API developers actually enjoy using
Amazon SES
The cheapest way to send email, and the most work
Mailgun
Transactional email infrastructure with the best inbound routing in the category
Postmark
Transactional email that arrives in seconds, because nothing else shares the pipe
Twilio SendGrid
The default transactional email API, plus a marketing product nobody buys it for
AWeber
The autoresponder that invented the category and never got acquired
Constant Contact
The small-business email incumbent, with events, nonprofits, and a phone number that works
Mailjet
Marketing campaigns and transactional email on one account, metered by emails sent
Sender
Best ValueThe most generous free tier in email marketing, from a bootstrapped Lithuanian team
Profiles are listed in editorial order. Placement cannot be purchased; see our methodology.