Secure transactional email SMTP relay for high volume senders

Send your transactional emails with confidence from your IP addresses and domains - no worries! Serenamail protects your network reputation and maximises email deliverability.

It’s not only your marketing teams that are sending large numbers of emails; your ERP systems or other CRM, SCM or mail servers also generate large volumes of transactional email such as paperless invoices, order forms, alerts, password recoveries, authentication codes, and appointment reminders. Leave the technical challenges to an email deliverability expert!

Maximised email deliverability

IP address and domain reputation protection

High priority routing for transactional emails

Secure SMTP self-care relay

SMTP Relay Features

Overcome the technical challenges related to bulk and large volumes of email campaigns. Serenamail SMTP relay optimises your outgoing email traffic according to the rules of the different inbox providers for carrier-grade performance.

High & stable delivery rate

Alinto’s clean traffic technology, along with our team of deliverability experts, works together to guarantee the highest delivery rates of your emails in your recipient’s inboxes.

Realtime traffic dashboard

Serenamail offers an advanced tracking and analytics interface, providing a real-time overview, log files, and self-care log access, thanks to the ELK stack.

Safety and Security

When sending high volumes of emails, safety and security are essential to protect your company’s domain reputation. Secured authentication, SSL, SPF/DKIM and sending rules are all work together to protect your IP reputation.

Easy scalability and flexibility

Serenamail is available as SaaS and is hosted & operated in our self-operated data centre. Serenamail can also be deployed on-premise or on a private cloud for very large configurations.

Quick answers: Transactional emails and SMTP relay

  • What is a transactional email?

    A transactional email is an automated message sent to a user in response to their online activity. These messages are personalized and typically contain important information relevant to the user’s action, including order confirmations, shipping notifications, password resets, purchase receipts, account updates, and personalized alerts.

  • What is the difference between a transactional email and a marketing email?

    Transactional emails are automated messages sent to individuals following specific actions, like purchases, account changes or password reset request. They provide information needed to complete or confirm a transaction, are personalized, timely, and necessary for user interactions. Marketing emails, however, are designed for promotional purposes. They are sent in bulk to engage groups of users, increase brand awareness, or market services and products. The key difference lies in their intent and trigger: transactional emails are responses to user activities, whereas marketing emails are initiated by the company’s marketing strategies.

  • What are examples of transactional emails?

    Transactional emails are automated messages sent to a user after specific interactions. Common types include:

    • Order Confirmations: Acknowledge a purchase, detailing the transaction.
    • Shipping Notifications: Provide updates on the delivery status of an order.
    • Delivery Confirmations: Informs that the ordered item has been arrived at destination.
    • Password Resets: Offer secure links for resetting account passwords.
    • Account Alerts: Notify of changes or activity in a user’s account.
    • Payment Invoices: Present invoices for services or products purchased.
    • Subscription Renewals: Send reminders about ongoing service subscriptions.
    • Support Tickets: Confirm a user’s request for help or feedback.
    • Double-opt in: Verify that email belongs to the subscriber, preventing spam and improving deliverability.
  • What is an SMTP server?

    A SMTP server is responsible for sending, storing, and receiving emails from one email provider to another. SMTP stands for Simple Mail Transfer Protocol, and it’s the standard technology for sending emails across the internet.

    There are two types of SMTP servers:

    • SMTP servers that manage day-to-day professional or private one-to-on email communication.
    • Dedicated SMTP servers designed for handling high volume emails, such as bulk marketing messages or transactional emails.
  • What is the difference between a SMTP server and an Email server?

    An SMTP server specifically handles the sending of emails by following the Simple Mail Transfer Protocol. An email server, however, plays a broader role, encompassing the SMTP functions as well as additional protocols like POP3 or IMAP, which are used for retrieving and storing emails. While SMTP is dedicated to sending emails, email servers manage the entire lifecycle of emails. This includes storing incoming mail, enabling users to access and organize their emails, and supporting the retrieval of emails across various devices.

    Typically, mail servers incorporate an integrated SMTP server, which is suitable for regular person-to-person email communications. Beyond a certain volume of emails or for specific security reasons (such as maintaining domain integrity or limiting sender IP addresses) a dedicated SMTP server can be employed alongside the email server.

  • When should I use a SMTP relay server?

    An SMTP relay server is recommended when you need to send large volumes of email securely, timely and reliably. It is particularly useful for businesses to ensure their emails reach the recipient’s inbox and not the spam folder. This service is crucial for maintaining a good reputation of your email domain, especially for important communications like transactional emails, marketing campaigns, and customer notifications. By using an SMTP relay, you reduce the risk of being blacklisted by ISPs and improve email deliverability. A SMTP server is your go-to solution, providing the infrastructure to handle both high volumes and the security protocols necessary for safe, effective email communication.

  • Why is it important to protect your domain when sending high transactional email volumes?

    Protecting your domain when sending high transactional email volumes is crucial for maintaining your email reputation. If your domain is perceived as a spam source, it can lead to your emails being blocked or marked as spam (including your company’s day-to-day business emails), impacting the reach and effectiveness of your communications. High email volumes can trigger spam filters, so using SMTP relay services to protect your domain ensures clean traffic and prevents damage to your domain’s reputation. This protection is essential for reliable email delivery and maintaining your business’s professional image.

  • Does Serenamail SMTP relay offer an API?

    Yes, Serenamail SMTP Relay includes a send API.

  • What is a carrier grade service?

    A carrier-grade service refers to a telecommunications service or system that is designed to meet the high standards and requirements of telecommunications carriers or service providers. These services are typically designed to provide high availability, reliability, scalability, and performance to meet the demands of large-scale networks and a large number of users.

Explore beyond Serenamail SMTP relay

Alinto provides a range of email solutions and services for companies looking for independent email solutions.

Cleanmail Antispam & Antivirus

A smart shield to protect your email communication from any risk and threats, including best-in-class email filtering & AI technology.


Business-class mail server for companies seeking for a proven European alternative.

Exchange in Cloud

The world’s most-used email server with the benefits of secure European cloud hosting.

Installation & Deployment

SaaS, on cloud or on-premise, you have the choice! As an experienced software solution and cloud hosting provider, we offer full flexibility and adapt to your priorities.

When you decide to adopt software to manage your company’s email, email deliverability or email security, apart from the choice of software, you also need to decide on either a SaaS, on cloud or an on-premises service. The choice will depend on many factors such as your technical equipment, your constraints in terms of internal resources and know-how, regulatory rules, operating vs capital expenditure etc. The criteria to be considered are multiple. When adopting Alinto email security solutions, all choices are possible. We put our expert team at your disposal to advise on the right choice for you.

  • Installation on premise

    Hardware & 3rd party software architecture: Alinto experts will prepare the suitable Hardware and 3rd party Software architecture in line with your requirements. High availability, redundancy, back up & recovery rules will be aligned with your business targets.

    System set up: Set up of hardware & 3rd party software is under the customer’s responsibility. Alinto’s expert teams will take care of the installation & configuration of Alinto Software.

    System operations: Upon request, Alinto also takes care of the day-to-day operation of the system (via remote access).

  • Installation on cloud

    The private cloud of Alinto is hosted in European Union: France, Switzerland or any other country depending on our customer’s requirements.

    24/7 Monitoring: The infrastructure is monitored 24/7 to guarantee the security and resilience of our customer’s services.

    99,9% network uptime: Replication and interconnection between data centres to guarantee very high network uptime

    Virtual Hosting: All Alinto solutions are available as SaaS ready to use – minimise your infrastructure, migration and maintenance costs

    Dedicated servers: All Alinto services and products are available on dedicated platforms. Upon your choice, they can be installed in the Alinto cloud, in the cloud of one of our European partners or a private/public cloud of your choice.

  • M&S - Maintenance and support

    Maintenance Services: Regular preventive and curative maintenance services are carried out by Alinto experts. Non-service impacting maintenance activities may be carried out during office hours in off-peak periods. Major interventions may take place outside working hours to limit the impact on service availability.

    Support Services: Alinto offers L2 and L3 support services during office hours. Response and resolution times will depend on subscribed SLA (service level agreement).

    Help desk: as part of support services, Alinto experts can be reached by email or phone.

See how Serenamail SMTP relay works

Request your free trial of Serenamail today. Start sending transactional emails and explore all the features of our SMTP mail relay. 

Simply fill out the form, and we will get back to help you get started.

mail relay device

Transactional emails for SMEs, public services and MSPs

SMEs and Public Organizations

Do you need to reach the next level of transactional email volumes? Overcome current limitations and IP reputation issues? Ensure that the growing volumes of transactional emails volumes are securely delivered on time to run your services smoothly?

Managed Service Providers

As an MSP, such as an online booking solution provider, your users expect confirmation, authentication, or reminder emails to arrive promptly in their inbox. To maintain an excellent level of customer experience, you need the ability to act quickly if something goes wrong.

SMTP mail relai desktop

A real-time traffic dashboard

Transactional emails are expected to arrive quickly. Track email deliverability performance in real-time via a simple administration interface and take action if performance falls below expectations.

mail relay meeting

Tailor-made services

Alinto offers ready-to-use and proven email & security solutions that can adapt to each company's need. Our experts accompany each project to create tailor-made solutions for complex environments.

Define routing priorities per usage

Policy elaboration

Sizing of the solution

Success stories

Companies all over Europe use Alinto’s technology and services to manage and secure their email services successfully. Learn how!

Use case – Citizen email service

In Success story,

A number of European local authorities, usually medium and large (…)

View details

Success Story Koln University

In Success story,

The University of Cologne integrates SOGo webmail solution to its (…)

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We would love to hear from you.

Whether you are curious about features, a demo or a free trial —we’re here to answer all your questions.

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