| 15Five 15five.com | HR Tech | Inbound email processing | USA |
| Acm-editorial acm-editorial.slack.com | Productivity | Email service provider | United States |
| Acquia acquia.com | Digital Experience Platform | Mailgun is an API-based email service that enables the email functionality in Acquia DAM. | San Antonio, TX 78205 |
| AgileCase agilecase.com | Productivity | Email Delivery Services | United States |
| Ai-affiliate-program ai-affiliate-program.com | Fintech | SMTP for sending emails to merchants and end customers. Mail servers are provided by Mailgun to deliver emails from the product. | USA |
| Airtable airtable.com | Productivity | Transactional email | USA, Germany, Belgium |
| Alliants Trust Centre alliants.com | Hospitality Technology | User facing transactional emails | USA |
| Anthology anthology.com | EdTech | Email Delivery | United States |
| Arta arta.io | E-commerce | Email service provider | United States |
| Ativion Data Processors ativion.com | EdTech | Transactional email delivery | US, EU |
| Atlassian opsgenie.com | DevOps, IT Service Management | Communications technology provider for product notifications | USA, EEA |
| Atlassian atlassian.com | Productivity, Software Development, DevOps | Communications technology provider for product notifications | USA, EEA |
| Atticus atticus.tech | Legal Tech | Application account management and emails. | EU |
| Beekeeper beekeeper.io | HR Tech | Email solution provider | EU |
| BioRender biorender.com | HealthTech | Customer communication | USA |
| Blackboard blackboard.com | EdTech | Email Delivery | United States |
| Bloomreach bloomreach.com | Marketing | Messaging | USA |
| Bugcrowd bugcrowd.com | Cybersecurity | Email services | USA |
| CertCrowd certcrowd.com | Compliance Management | Transactional email delivery | EU (Germany) or USA |
| Chargebee chargebee.com | Billing & Subscription Management | Email delivery service provider | USA |
| CircleCI circleci.com | DevOps | Product related emails (system notifications) | United States |
| Clerk clerk.io | E-commerce, AI/ML | Email delivery infrastructure | United States |
| Cobrowse.io cobrowse.io | Customer Experience Technology | Transactional Email | San Antonio, Texas |
| CoderPad coderpad.io | DevOps | Supporting business operations | USA |
| ConfigCat configcat.com | DevOps | Email delivery services | United States |
| Customer Service Support and In App Ticketing System aihelp.net | Customer Support Technology | For email-based support, all incoming and outgoing emails are processed by the Mailgun messaging engine. These emails contain the support dialog with the end user and may contain personal data. | United States |
| CyberArk venafi.com | Cybersecurity | Email delivery platform | United States |
| CyberArk cyberark.com | Cybersecurity | Email delivery platform | United States |
| Datadog datadoghq.com | Cloud Infrastructure | Email and office applications | United States |
| Docusign docusign.slack.com | N/A | Email service provider for all functionality. | United States |
| DroneDeploy dronedeploy.com | Construction Tech, AI/ML | Email distribution | United States |
| Duffel duffel.com | Travel Tech | Transactional emails e.g. password reset | US |
| Employ Inc. employinc.com | HR Tech | Messaging & Notifications | USA |
| esendex.co.uk esendex.co.uk | Communication Technology | Email Provider | Europe |
| Everafter everafter.ai | Customer Engagement, AI | Transactional mail services provider | EU |
| Feedly feedly.com | Market Intelligence, Cybersecurity | Email Delivery | United States |
| Freshworks freshworks.com | Customer Experience, AI/ML | Used by Freshsuccess as an email service provider to deliver bulk email campaigns. | US |
| GitLab gitlab.com | DevOps | Transactional Email APIs | United States and European Union |
| Gong gong.io | Sales Enablement | Transactional email | USA, EU |
| Hacksplaining hacksplaining.com | Cybersecurity | Transactional email delivery | United States |
| Harmonizehq harmonizehq.slack.com | Collaboration Software | Email service provider for all functionality | United States |
| Helloretail helloretail.com | E-commerce | Email services | 112 E Pecan St #1135, San Antonio, TX 78205, USA |
| HelloSign hellosign.com | Cloud Infrastructure | Electronic Mail | United States |
| Helpshift helpshift.com | Gaming/Player Engagement | Email Processing | USA |
| inFeedo AI infeedo.ai | HR Tech | Email service provider | USA/Germany/Belgium |
| Intercom intercom.com | Customer Service Technology, AI Solutions | Email delivery services for individual emails and bulk email campaigns initiated from Intercom's services. | Belgium |
| Intercom intercom.com | Customer Service Technology, AI Solutions | Email delivery services for individual emails and bulk email campaigns initiated from Intercom's services | USA |
| JazzHR jazzhr.com | HR Tech | Messaging & Notifications | USA |
| JFrog jfrog.com | DevOps | Email notification services | United States |
| Jobilla jobilla.com | HR Tech | Email Service Provider | USA |
| Jobvite jobvite.com | HR Tech | Messaging & Notifications | USA |
| Lever lever.co | HR Tech | Messaging & Notifications | USA |
| Litestream litestream.slack.com | N/A | Email service provider for all functionality | United States |
| Logit logit.io | Log Management, DevOps | Email | United States |
| Lusha lusha.com | Data Enrichment | Customer Email Validation | Germany |
| Mailgun mailgun.com | Email Delivery, SaaS | Email sending and marketing service | United States |
| Mobile2b mobile2b.com | Business Process Management, Workflow Automation | Email Sending | EU |
| Monday.com monday.com | Productivity, Collaboration Software, AI | Email notification service | US |
| NextRoll nextroll.com | AdTech | Sending emails | USA |
| Notion notion.so | Productivity | Transactional, broadcast, and marketing messaging | USA |
| OnceHub oncehub.com | Productivity | Backup email relay services | USA |
| OpenSesame opensesame.com | EdTech | Email | USA |
| Ora ora.pm | Productivity | Cloud-based Email Notification Services | United States |
| PagerDuty jeli.io | DevOps | Email Notification Services | United States, Belgium, Germany |
| PagerDuty pagerduty.com | DevOps | Email Notification Services | United States, Belgium, Germany |
| PandaDoc pandadoc.com | Document Management | Email Delivery | United States |
| Productive productive.io | Professional Services Automation | Cloud-based Email Notification Services | United States |
| Rackspace rackspace.com | Cloud Infrastructure, AI/ML | Products & Services – Email & Apps | US |
| Replit replit.com | DevOps | Marketing | USA |
| Retool retool.com | Low-code Development | Third-party service provider for sending Retool Email | United States |
| Riot tryriot.com | Cybersecurity | Client emailing | United States |
| Samsara samsara.com | IoT and Fleet Management | Customer communications | USA |
| Sinch sinch.com | CPaaS (Communications Platform as a Service) | Developer-first, scalable, and reliable infrastructure for sending transactional and marketing emails. | USA |
| Smartsupp smartsupp.com | Customer Engagement, AI Chatbots, SaaS | Used for the delivery of email messages, which is necessary for the operation of the Service. | EU hosting center |
| Spark Hire sparkhire.com | HR Tech | Transactional email | United States |
| Squadcast squadcast.com | DevOps | Email delivery service | USA |
| Strise strise.ai | Fintech | Email notifications and updates | GCP in Germany & Belgium, AWS in Germany |
| Sub Processors quinncia.io | EdTech | Email marketing | USA |
| Sub Processors officernd.com | Workplace Management | Transactional email sending | EU |
| Sub Processors Business Data exact.com | Fintech | Processing of email | USA |
| Sufio sufio.com | Fintech | Email Notification Services | United States |
| Superbly superbly.education | EdTech | Communications technology provider for product notifications | USA |
| Supermetrics supermetrics.com | Marketing Analytics | Mail sending and receiving services | USA |
| Supermetrics davinci.tools | Marketing Technology | Mail sending and receiving services | USA |
| Svix svix.com | Developer Tools | Primary email relay to send emails to customers as part of the Svix services. | TX, USA |
| Talkable talkable.com | Marketing | providing Talkable with managed email deliveries | USA |
| Taskagi taskagi.net | AI/ML, Automation | Marketing and transactional email | USA, EU (Ireland) |
| Teamleader teamleader.eu | Productivity | Functionality: Email services for the Tickets module | USA |
| Team O'clock teamoclock.com | Productivity | Email delivery | United States |
| Telnyx telnyx.com | Telecommunications, Voice AI | Service used for sending, receiving, and tracking transactional emails via API. | San Francisco, CA, USA |
| Tempo tempo.io | Productivity, Project Management, AI | Sending transactional emails, such as account activations, password resets, order confirmations, and other communications. | United States |
| ThoughtSpot thoughtspot.com | Analytics, AI/ML | Email notification services. | USA |
| Timely gettimely.com | HealthTech | Cloud-based email notification services | United States |
| Tradeshift tradeshift.com | Fintech, AP Automation, E-Invoicing | Product notification email provider | United States |
| Transcribe transcribe.wreally.com | AI/ML | Email management and sending service | United States |
| Trusted Family trustedfamily.com | — | Email delivery | EU |
| Trustmary trustmary.com | Customer Experience Management | Messaging, transactional messages | EU/EEA |
| Tunepact tunepact.com | Music Marketing | Transactional emails (alternative provider) | USA |
| Usercheck usercheck.com | Email Validation, Cybersecurity | Email delivery | EU |
| V2 v2.slack.com | Unknown | Email service provider for all functionality | United States |
| Vectara vectara.com | AI/ML | Product Services – Email Service Provider | United States |
| Wix wix.slack.com | Productivity | Email service provider for all functionality | United States |
| Workable workable.com | HR Tech | An e-mail service provider. | San Antonio, TX 78205, United States |
| Xero xero.com | Fintech | Transactional email processing | United States |
| xMatters xmatters.com | DevOps | Mailgun is a primary provider of email notifications to users of the xMatters platform. | United States |