44 Best Email API's for Developers in 2025
Reviews, comparison, screenshots and more for the 44 best email service API's for developers.
Email API Comparison
| Email Service | Pricing | Storage | Attachments | Open-Source | Sandboxed Encryption | Unlimited Domains | Unlimited Aliases | TTI | SMTP | IMAP | POP3 | API | E2EE | OpenPGP | WKD |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Forward Email⭐ PreferredEmail for everyone | $3/mo | 10 GB pooled | 50 MB | Yes | Yes | Yes | Yes | TTI | Yes | Yes | Yes | Yes | ⚠️ Opt-in | Yes | Yes |
GmailSecure, smart, and easy to use email | $7.20/mo | 30 GB pooled | 25 MB | No | No | No | No | No | Yes | Yes | Yes | Yes | No | No | No |
ResendEmail for developers | $20/mo | No Resend does not support storage | 40 MB | No | No | Yes | Yes | No | Yes | No | No | Yes | No | No | No |
PostmarkThe email delivery service that people actually like | $15/mo | No Postmark does not support storage | 10 MB | No | No | No | No | TTI | Yes | No | No | Yes | No | No | No |
ImprovMXCreate free email aliases for your domain name | $9/mo | No ImprovMX does not support storage | 50 MB | No | No | No | No | TTI | Yes | No | No | Yes | No | No | No |
Get ResponseAn affordable, easy platform to send emails, grow your list, and automate communication | $187.20/yr | No Get Response does not support storage | 0.4 MB | No | No | Yes | Yes | No | Yes | No | No | Yes | No | No | No |
ActiveCampaignPostmark, the leading service for transactional email, is now part of ActiveCampaign | $15/mo | No ActiveCampaign does not support storage | 10 MB | No | No | No | No | TTI | Yes | No | No | Yes | No | No | No |
SMTP.comTransactional and email relay API | $25/mo | No SMTP.com does not support storage | 15 MB | No | No | No | No | No | Yes | No | No | Yes | No | No | No |
SendgridGet your emails to the inbox—where they belong | $19.95/mo | No Sendgrid does not support storage | 30 MB | No | No | No | No | No | Yes | No | No | Yes | No | No | No |
SMTP2GOLike a first-class courier, for email | $10/mo | No SMTP2GO does not support storage | 50 MB | No | No | No | No | No | Yes | No | No | Yes | No | No | No |
MessageBirdOmnichannel automation platform for APIs, service & marketing | $20/mo | No MessageBird does not support storage | 100 MB | No | No | No | No | No | Yes | No | No | Yes | No | No | No |
MailtrapEmail Delivery Platform that delivers just in time. Great for businesses and individuals | $10/mo | No Mailtrap does not support storage | 10 MB | No | No | No | No | No | Yes | No | No | Yes | No | No | No |
MailjetEffortlessly create and deploy marketing and transactional emails in one place | $15/mo | No Mailjet does not support storage | 15 MB | No | No | No | No | No | Yes | No | No | Yes | No | No | No |
MailgunFlexible, scalable, and results driven email sending platform | $35/mo | No Mailgun does not support storage | 25 MB | No | No | No | No | No | Yes | No | No | Yes | No | No | No |
MailerSendIntuitive email API and SMTP | $288/yr | No MailerSend does not support storage | 25 MB | No | No | No | No | No | Yes | No | No | Yes | No | No | No |
HubSpotGrow better with HubSpot | $890/mo (varies, some plans do not include SMTP) | No HubSpot does not support storage | 20 MB | No | No | No | No | No | Yes | No | No | Yes | No | No | No |
Elastic EmailTake your email marketing and email delivery to the next level | $9/mo | No Elastic Email does not support storage | 10 MB | No | No | No | No | No | Yes | No | No | Yes | No | No | No |
Customer.ioSend messages people actually want to receive using real-time customer data | $100/mo | No Customer.io does not support storage | 2 MB | No | No | No | No | No | Yes | No | No | Yes | No | No | No |
BrevoThe most approachable CRM to cultivate lasting customer relationships across Email, SMS, Chat and more | $15/mo | No Brevo does not support storage | 20 MB | No | No | No | No | No | Yes | No | No | Yes | No | No | No |
Amazon Simple Email Service (SES)Get reliable, scalable email to communicate with customers at the lowest industry prices | $X/mo; varies, using shared IP's from SES are known to have negative effect on deliverability | No Amazon Simple Email Service (SES) does not support storage | 10 MB | No | No | No | No | No | Yes | No | No | Yes | No | No | No |
MandrillReach inboxes when it matters most | $33/mo | No Mandrill does not support storage | 25 MB | No | No | No | No | No | ❌ Requires paid add-on for Mandrill of at least $20/mo | No | No | Yes | No | No | No |
MailchimpTurn Emails into Revenue | $33/mo | No Mailchimp does not support storage | 25 MB | No | No | No | No | No | ❌ Requires paid add-on for Mandrill of at least $20/mo | No | No | Yes | No | No | No |
IntercomThe only AI customer service solution you need | $39/mo | No Intercom does not support storage | 20 MB | No | No | No | No | No | No | No | No | ❌ See blog post | No | No | No |
Email API Screenshots
Forward Email
Forward Email is an open-source email service. Their website says: Email for everyone
Gmail
Gmail is a closed-source email service. Their website says: Secure, smart, and easy to use email
Resend
Resend is a closed-source email service. Their website says: Email for developers
Postmark
Postmark is a closed-source email service. Their website says: The email delivery service that people actually like
ImprovMX
ImprovMX is a closed-source email service. Its description from its website is: Create free email aliases for your domain name
Get Response
Get Response is a closed-source email service. Their website says: An affordable, easy platform to send emails, grow your list, and automate communication
ActiveCampaign
ActiveCampaign is a closed-source email service. Its description from its website is: Postmark, the leading service for transactional email, is now part of ActiveCampaign
SMTP.com
SMTP.com is a closed-source email service. According to their website: Transactional and email relay API
Sendgrid
Sendgrid is a closed-source email service. According to their website: Get your emails to the inbox—where they belong
SMTP2GO
SMTP2GO is a closed-source email service. Their official description reads: Like a first-class courier, for email
MessageBird
MessageBird is a closed-source email service. Its description from its website is: Omnichannel automation platform for APIs, service & marketing
Mailtrap
Mailtrap is a closed-source email service. Its description from its website is: Email Delivery Platform that delivers just in time. Great for businesses and individuals
Mailjet
Mailjet is a closed-source email service. According to their website: Effortlessly create and deploy marketing and transactional emails in one place
Mailgun
Mailgun is a closed-source email service. Their website says: Flexible, scalable, and results driven email sending platform
MailerSend
MailerSend is a closed-source email service. Their official description reads: Intuitive email API and SMTP
HubSpot
HubSpot is a closed-source email service. Its description from its website is: Grow better with HubSpot
Elastic Email
Elastic Email is a closed-source email service. Its description from its website is: Take your email marketing and email delivery to the next level
Customer.io
Customer.io is a closed-source email service. According to their website: Send messages people actually want to receive using real-time customer data
Brevo
Brevo is a closed-source email service. Their official description reads: The most approachable CRM to cultivate lasting customer relationships across Email, SMS, Chat and more
Amazon Simple Email Service (SES)
Amazon Simple Email Service (SES) is a closed-source email service. Their website says: Get reliable, scalable email to communicate with customers at the lowest industry prices
Mandrill
Mandrill is a closed-source email service. Its description from its website is: Reach inboxes when it matters most
Mailchimp
Mailchimp is a closed-source email service. Their website says: Turn Emails into Revenue
Intercom
Intercom is a closed-source email service. Their official description reads: The only AI customer service solution you need
