Heysender

What Heysender is

Heysender is a Danish transactional email service that describes itself as a "European email API". It handles the messages an application or online shop sends to one customer at a time after something happens: order confirmations, shipping information, password resets and login details. The homepage speaks to two groups, developers who would rather not spend their time on email plumbing, and support teams that need customers to receive those messages. The company lists an address in Aarhus, Denmark, in its footer and says it draws on more than 20 years in the email industry. Senders reach it in two ways, through an API with official SDKs or through SMTP credentials that an existing system can use, and the pitch rests on three things: getting mail delivered, logs that explain what happened to each message, and support staff you can actually reach.

Getting set up

The homepage promises that you can "Sign up and send your first email within 5 minutes", and the route it shows is short. You request access, then authenticate every call with a pair of credentials, an API key and an API secret, which each SDK example passes when it creates the client. Sending domains are managed through the same API. The code samples create a domain, optionally with a custom selector for its DKIM record, read back whether the domain has been validated, list the domains on the account and delete one that is no longer needed. Next to the API documentation, the site offers DNS tools and a knowledge base.

For SMTP, Heysender works with SMTP users tied to a domain. The examples create an SMTP user for an address on one of the account's domains, and the response returns the login email and a generated password, which is what a web shop, CMS or framework needs in its outgoing mail settings. You can list every SMTP user on a domain, so an account can hold several logins per domain.

Sending through the API

A message is assembled with a builder in each SDK. It takes a sender address and sender name, a subject and an HTML body, then recipients in To, CC and BCC, each with an optional display name. Two further options matter for day-to-day work. Tracking can be switched on or off per message, and messages can carry tags as key and value pairs; the C# sample tags a welcome email with campaign set to welcome-series and segment set to new-users. Custom headers are supported too, shown with an X-Campaign-ID header. When the message is sent, the API returns one response per recipient with a status, a message ID and the recipient address, which gives an application an ID to keep for every copy it sends.

Official SDKs cover six languages: C#, PHP, Python, Ruby, Go and Node.js. The homepage shows the same three tasks in each of them, sending a message, creating a domain and creating an SMTP user, so a team can compare the calls in its own language before it writes any code.

Anonymized sending

One feature stands out for a privacy-minded buyer. The SDK examples show anonymize options on both individual messages and SMTP users, with three values in use: recipient, subject and content. The PHP example anonymizes the content of a message, the Python and Ruby examples the content and the subject, and the Go example the recipient and the content, while the SMTP user examples combine the same values. For a sender whose password resets, account notices and order mails carry personal data, this is a way to limit the personal information kept about each message, and it sits alongside the data protection commitments described below.

Logs and troubleshooting

The log is the feature Heysender puts first after delivery. It gives an overview of your outgoing emails, and when a message has failed, Heysender says it offers an explanation of the error so you can fix the cause and send the email again. The homepage frames this around a familiar support problem: a customer says an order confirmation, shipping information or a password reset never arrived, and the team has no way to find out why. In the company's words, "most transactional email services offer very little or no insight for troubleshooting". Heysender's answer is that a support agent can look the message up, see what went wrong and resend it, instead of resending blindly and hoping for a better result. Its own summary of the service is a high deliverability rate, access to logs and quick support.

Deliverability

Heysender ties its deliverability to experience. The homepage says that, based on more than 20 years in the email industry, the company always follows best practice so it can offer an email service with a high deliverability rate. Around that claim, the site publishes an anti-spam policy, a public system status page and the DNS tools mentioned above, and domain validation with a DKIM selector is part of the API itself. The company blog covers the practical side of staying out of the spam folder: email blacklists and how to avoid them, keeping an email list clean, using subdomains to separate email traffic, phishing, and sender profile validation.

Data location and security

Data protection is a large part of the pitch. The homepage says: "We store all data within the EU and only use european data suppliers." It adds that all data is encrypted using SSL and TLS, and it names GDPR as one of the company's top priorities; the page title itself reads "European & GDPR compliant". Heysender also publishes an ISAE 3000 report, which it presents as part of its efforts to ensure the highest level of data security for customers. The report is linked from the homepage, and the footer links the ISAE 3000 documentation next to a Data Protection Agreement and the terms and conditions.

Support and customers

Support is free, the homepage says, and reachable "by phone, chat or email". Three named customers vouch for the service on the same page. Drope's CTO says the company uses Heysender for login information, where users cannot wait, and values being able to contact support directly instead of filling out a form and waiting. A technical manager at Visma IMS says it chose Heysender as the ESP for its software solutions because of its stability, prompt delivery and GDPR compliance, and describes the support team as always accessible. Playable's CPO calls it a trustworthy and fully GDPR-compliant solution that has made it easier to integrate Playable's platform among its customers. Heysender also runs a partner program and offers branding material for partners.

Plans and pricing

The homepage quotes no prices. Pricing sits on a separate page, and the main calls to action are to get access or to contact the company to learn more.

SMTP or API

Heysender's blog has a post on when each route fits. SMTP, it says, demands one request per email, which makes it slow for a large number of emails, and it is often used for transactional emails such as user information, order confirmations and password resets. The API is described as more flexible and more feature-rich, better suited to bulk sending and to designed marketing emails. Because Heysender offers both, a shop can start with SMTP credentials in its platform's mail settings and move to the API once it wants tags, tracking and anonymize options on each message.

Who it suits

Heysender suits European companies that send transactional email from their own software and care where the data lives: SaaS products sending logins and password resets, web shops sending order and shipping mail, and software vendors like the ones quoted on the homepage. Teams whose support staff field complaints about missing emails get the most from the log and resend workflow, and teams with a data protection officer will value the EU-only storage, the ISAE 3000 report and the anonymize options. Developers get SDKs in six languages, and SMTP covers systems that cannot call an API.

It is a narrower tool than an all-in-one marketing platform. Heysender presents itself as a transactional service, so a sender planning newsletters and drip sequences would pair it with a separate marketing tool. Budget planning also takes a step more than usual, because the homepage leads with getting access and talking to the company rather than with plan prices.