Best SMTP Services for Courier

Email is the backbone of your customer engagement. The Twilio SendGrid Email API is the email service trusted by developers and marketers for time-savings, scalability, and delivery expertise. Our flexible Email API and proprietary Mail Transfer Agent (MTA), intuitive console, powerful features, and email experts make it easy to ensure all your email gets delivered in seconds and without interruption. Monitor engagement data and optimize deliverability with our Deliverability Insights dashboard. Whether you’re sending 100 emails or 100 billion, SendGrid is built to scale. Integrate with our RESTful APIs and SMTP in minutes, with sample code libraries available in 7 languages, interactive docs, templates, and more.

Bird (formerly MessageBird) is the next-generation CRM for Marketing, Sales, and Payments, powering over 5 trillion annual messages across Email, SMS, and WhatsApp. Leading brands grow cost-efficiently with Bird through personalized interactions on Email, SMS, and WhatsApp. The world's most innovative companies build communication solutions using Bird's applications and APIs. Get started today and talk to your customers over any channel, for any use case, anywhere in the world. Marketing messages, push notifications, order updates, delivery alerts and more. Operational bottlenecks slowing your growth? Use automated conversations and workflows to collect critical information up front, reduce manual tasks, implement self-service flows, and route chats to the right agent. Get up and running in minutes on our reliable, auto-scaling APIs with extensive documentations, complete API references and intuitive SDKs.

Amazon Simple Email Service (SES) is a cost-effective, flexible, and scalable email service that enables developers to send mail from within any application. You can configure Amazon SES quickly to support several email use cases, including transactional, marketing, or mass email communications. Amazon SES's flexible IP deployment and email authentication options help drive higher deliverability and protect sender reputation, while sending analytics measure the impact of each email. With Amazon SES, you can send email securely, globally, and at scale. Using either the Amazon SES console, APIs, or SMTP, you can configure email sending in minutes. Amazon SES also supports email receiving, enabling you to interact with your customers at scale. Regardless of use case or sending volume, you only pay for what you use with Amazon SES.

MailerSend is a transactional email and SMS service designed for developers to work faster and smarter. A drag & drop builder and dynamic templates enable anyone at any skill level to create personalized transactional emails, while our SMS templates help you create professional transactional SMS messages. MailerSend’s advanced infrastructure scales with your sendings, while the latest security protocols protect your sender reputation. Plus, you can integrate your email sending and tracking in your apps using SMTP or a flexible email API. Built by deliverability experts, and with the inbuilt email verification tool, you can rest easy knowing your messages will be delivered and avoid spam folders, while dedicated IPs are available for high-volume senders. Plus, inbound routing enables your customers to interact with your messages, sparking conversations and increasing engagement. Get started for FREE with 500 emails, then upgrade for as little as $7/month for up to 5000 emails.

Transactional emails: Reach inboxes when it matters most. Deliver fast, personalized transactional emails using API or SMTP. Get the benefits of our experience sending billions of emails globally. Send personalized transactional emails that reach inboxes, not spam folders. Customize your analytics with pre-built dashboards, export API, and more. Read documentation guides, or contact our award-winning Support team for help. Use custom tagging, whitelabeling, conditional content, and more. Globally distributed infrastructure: Featuring automatic SPAM loop registration and pre-warmed dedicated IPs. Get analytics in multiple ways, plus custom tags, A/B test capabilities, and comparative reports. Utilize white-labelled click tracking, custom reverse DNS, rules engine, custom return path, and sub-accounts. That’s the average time to delivery for top 3 ISPs, sent from our MTAs to the recipient’s email server.

Mailgun is an email automation solution that is suitable for developers. With Mailgun, users are able to access a complete cloud-based email service for tracking, sending, and receiving emails sent via their applications and websites. Mailgun supports several programming languages including Python, Ruby, PHP, Java, and C#. With Mailgun's tracking feature, users are able to track all emails and reduce the chances of getting spam.