Company lists · Data refreshed September 2026
Top 25 Transactional email services worldwide
RevenueBase identified 345 transactional email services worldwide as of September 2026 and tracks 4,701 professional contacts across them, including 1,662 with verified work emails. The United States is the largest market and New York the largest hub.
This list covers transactional email services worldwide, matched on what each company actually does as described in its own words. Ranked by team size, largest first. Every row shows the company's own description, its RevenueBase Smart Search rating, and when it was last checked. Data refreshed September 22, 2026. Country and city lists for transactional email services follow the table.
Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase Smart Search, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.
The 25 largest transactional email services worldwide
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 446 contacts → | ||||
Indirect evidence “Create personalized customer journeys that engage and convert with our versatile customer engagement platform.” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
| 2 | 197 contacts → | ||||
Indirect evidence “Our mission is to solve customer experience.” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
| 3 | 190 contacts → | ||||
Partial evidence “Sinch Mailgun is the leading email delivery service for businesses around the world.” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
| 4 | 141 contacts → | ||||
Partial evidence “Kit is the email marketing platform built for creators who mean business.” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
| 5 | 134 contacts → | ||||
Indirect evidence “Sendinblue is now @Brevo” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
| 6 | 122 contacts → | ||||
Partial evidence “In 2005, we started as a web design agency, but we soon discovered email marketing and fell in love with it.” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
| 7 | 115 contacts → | ||||
Partial evidence “Benchmark helps busy marketers move faster and make a bigger impact with email.” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
| 8 | 94 contacts → | ||||
Partial evidence “Everlytic is a marketing messaging and automation platform that helps your business communicate better, smarter, and faster over email, SMS, voice broadcasting and web push.” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
| 9 | 90 contacts → | ||||
Indirect evidence “Inxmail ist der serviceorientierte Tech-Spezialist für sichere, datengetriebene Kommunikation im E-Mail-Marketing.” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
| 10 | 88 contacts → | ||||
Partial evidence “Mailmodo is a complete email marketing solution enabling users to create and send app-like interactive emails to improve email conversions.” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
| 11 | 86 contacts → | ||||
Indirect evidence “Your data holds more potential than you think.” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
| 12 | 80 contacts → | ||||
Indirect evidence “Activa tus estrategias de marketing, personaliza cada interacción, toma decisiones basadas en datos y maximiza tu performance a través de nuestra plataforma de marketing…” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
| 13 | 68 contacts → | ||||
Indirect evidence “Ecomail je moderní e-mail marketingová platforma pro rozesílku newsletterů a SMS, automatizovaný e-mailing a rychlý růst databáze kontaktů.” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
| 14 | 61 contacts → | ||||
Partial evidence “UniSender is a №1 email and SMS sending service in the CIS region.” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
| 15 | 56 contacts → | ||||
Partial evidence “Email for developers” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
| 16 | 51 contacts → | ||||
Partial evidence “Automatically target customers based on how they interact across all channels: email, SMS, Facebook Messenger.” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
| 17 | 47 contacts → | ||||
Partial evidence “All the email marketing and delivery tools you need to communicate with your customers.” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
| 18 | 47 contacts → | ||||
Partial evidence “SMTP is one of the early pioneers of cloud-based email services and is now part of Ziff Davis, Moz Group and Campaigner.” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
| 19 | 46 contacts → | ||||
Partial evidence “Truly unified email, SMS, reviews, and forms.” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
| 20 | 46 contacts → | ||||
Indirect evidence “CleverReach ist eine der führenden Lösungen für E-Mail Marketing.” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
| 21 | 45 contacts → | ||||
Strong evidence “Kasplo is a cloud-based email delivery and management service designed to help businesses send transactional and marketing emails on a large scale.” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
| 22 | 38 contacts → | ||||
Indirect evidence “MessageFlow is a send-it-all platform that makes cross-channel communication easy and effective.” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
| 23 | 38 contacts → | ||||
Indirect evidence “A SendPulse é uma plataforma de marketing orientada por IA para negócios prontos para escalar, ajudando a automatizar e-mail marketing e chatbot para WhatsApp.” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
| 24 | 38 contacts → | ||||
Partial evidence “SendGrid is a proven cloud-based customer communication platform that successfully delivers over 45 billion emails each month for Internet and mobile-based customers like Airbnb…” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
| 25 | 35 contacts → | ||||
Partial evidence “We are a marketing technology company that provides a state-of-the-art email, SMS & web-marketing platform.” Source: RevenueBase Database · checked Sep 22, 2026Thanks. The Data Team will review it. | |||||
RevenueBase Smart Search
RevenueBase Smart Search assesses information from a company’s LinkedIn profile, information supplied directly by the company, its website, and other publicly available sources. It uses that information to rate how closely the company relates to this list’s category: transactional email services. Every row carries its rating and the description the rating was read from, so each one can be checked rather than taken on trust.
- Strong evidence
- The company's own public description of its business names transactional email services.
- Partial evidence
- Its own public description names part of transactional email services, so it works in or next to the category without describing itself that way.
- Indirect evidence
- The description shown does not name transactional email services. The match rests on the rest of the company's public profile rather than the one sentence quoted here, so this is the rating to check first.
RevenueBase Smart Search is how these lists are built: RevenueBase's data engine and AI assemble the companies that match a category defined in a user's own words, so a list can be about what companies actually do rather than about whichever industry code they were filed under.
Showing 25 of 345 transactional email services worldwide
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Transactional email services worldwide at a glance
As of Sep 22, 2026Companies by employee count
Email recency is reported on each country list linked below.
How this list was built
Company categories are rarely black and white. RevenueBase reads each company's own description of its business to decide whether it belongs among transactional email services, so some rows will be adjacent to the category rather than pure plays. The description and RevenueBase Smart Search rating on every row are there so you can check each match yourself.
- Source
- The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase Smart Search, the natural-language company search available to every RevenueBase user.
- Coverage
- Every country. Country and city lists for transactional email services are linked below.
- What qualifies
- Companies worldwide whose own description of what they do matches “transactional email services”. Matching reads each company's description, not its industry code or its name.
- RevenueBase Smart Search
- RevenueBase Smart Search is how this list is assembled and how each row is rated. RevenueBase's data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to a category defined in a user's own words. Each row is rated strong evidence (its own description names transactional email services), partial evidence (it names part of the category) or indirect evidence (the description shown names none of it and the match rests on the rest of the company's profile). The description supporting each rating is quoted on the row.
- What we exclude
- Companies whose own description does not clearly place them among transactional email services, and records with no verified work email.
- Match quality
- In blind human judging of this matching method, 86% of matched companies were on target. Expect roughly 1 in 7 rows to be adjacent to the category rather than a pure play. Every row shows the company's own description and its RevenueBase Smart Search rating so you can judge each match yourself. Read the full methodology: how the lists are built, how the judging worked, and what the figure means.
- Ranking
- Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
- Verification
- Every listed company carries at least one verified work email, 1,662 across the full list. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
- Refresh
- This page's figures were pulled from the company graph on September 22, 2026. Lists refresh periodically as the graph is re-checked.
- Corrections
- Wrong category, wrong headquarters, or a company that has closed? Use “Report an issue” on any row. Reports go to the RevenueBase Data Team and feed back into the company graph.
Transactional email services by location
1 lists · largest firstEvery Transactional email services list RevenueBase publishes, by country and city. Counts are matching companies in each list as of its own refresh date.
Countries
Frequently asked
What is RevenueBase Smart Search?
RevenueBase Smart Search is how RevenueBase decides which companies belong on this list and how strongly each one fits. Its data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to the category the list is about. Each row is rated strong evidence when the company's own description names transactional email services, partial evidence when it names part of the category, and indirect evidence when the description shown names none of it and the match rests on the rest of the company's profile.
How many transactional email services are there worldwide?
RevenueBase identified 345 transactional email services worldwide as of September 2026, matched on each company's own description of what it does rather than its industry code.
What is the largest company on this list?
customer.io, headquartered in Portland, tops this list with the largest team on record.
Which country has the most transactional email services?
The United States leads with 71 companies. Every transactional email services list by country and city is linked on this page.
Which city has the most transactional email services?
New York leads with 10 headquartered companies, followed by Austin (8) and London (5).
How do I get contact information for these companies?
A free RevenueBase account lets you run this exact search and work the top results, verified emails and direct dials included. Upgrading unlocks all 1,662 verified decision-maker contacts tracked across these 345 companies.
How current is this list?
The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 22, 2026.
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About this data
RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase Smart Search, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.