REST API · Finnish company · GDPR-focused

EU Transactional Email API — Operated Under EU Law

A transactional email API operated by Infotech Pioneers Oy — a Finnish company subject to EU law and outside US CLOUD Act jurisdiction. REST, signed webhooks, pre-signed Article 28 DPA. Sandbox key ready on signup, 1,000 free sends.

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Quick Answer

An EU transactional email API sends one-to-one, event-triggered emails (password resets, order confirmations, alerts) from infrastructure operated under EU jurisdiction — important for organisations whose Data Protection Impact Assessment must answer the Schrems II question. NexusProMail is operated by Infotech Pioneers Oy, a Finnish company subject to EU law, with a pre-signed Article 28 DPA, signed-HMAC webhooks and suppression-list enforcement at the API layer. Sandbox API key issued on signup; 1,000 free sends with no credit card.

Key Takeaways

  • Transactional emails are triggered by user actions; marketing emails are sender-initiated — different consent rules apply
  • Always send from a dedicated subdomain (e.g. mail.yourdomain.com) separate from your marketing sending domain
  • Register webhook endpoints to receive real-time events for bounces, complaints, opens and unsubscribes
  • The sandbox API key works immediately on signup — no DNS setup required for initial testing
  • The API enforces suppression automatically — attempting to send to a suppressed address returns a 422 response

Why EU Companies Choose This Transactional API

The transactional API feature set is roughly comparable across all major ESPs. The differences that matter for EU teams are jurisdictional.

Operator under EU law

Infotech Pioneers Oy is a Finnish company subject to EU regulation. The operator’s jurisdiction — not just the data centre — is what GDPR Article 44 and your DPIA care about.

Pre-signed Article 28 DPA

Every paid plan includes a pre-signed Data Processing Agreement referencing Article 28 obligations, our current sub-processors and an EU jurisdiction clause. No legal back-and-forth.

Schrems II compatible

No third-country transfer in the processing chain — the Standard Contractual Clauses + Transfer Impact Assessment workflow does not apply. Cleaner DPIA for buyer-side legal review.

EU data residency roadmap

Current AWS region: us-east-1. Migration to eu-west-1 (Ireland) is planned for Q3 2026. All processing today is governed by Finnish law regardless of where it physically runs.

CLOUD Act outside scope

A Finnish company is not subject to US legal compulsion frameworks (CLOUD Act, FISA 702). For sectors that must document this exposure in procurement, this is a meaningful distinction.

Sub-processor transparency

Current sub-processor list is published and the DPA carries change-notice clauses. You see what we change and you can object before it takes effect.

Comparing options? SendGrid EU alternative · Mailgun EU alternative · Resend EU alternative

Quick Start

Send your first email in under 5 minutes

Sign up, copy your sandbox key and make your first API call. The sandbox environment mirrors production — when you go live, only the key changes.

  • Sandbox key available immediately on signup
  • No DNS setup required for initial testing
  • Production key activates after domain verification
  • Same endpoints for sandbox and production
Node.js — send a transactional email
const res = await fetch(
  'https://app.nexuspromail.com/api/v1/api/send',
  {
    method: 'POST',
    headers: {
      'Authorization': 'Bearer YOUR_API_KEY',
      'Content-Type': 'application/json',
    },
    body: JSON.stringify({
      to: 'user@example.com',
      from: 'hello@yourdomain.com',
      subject: 'Your password reset link',
      html: '<p>Click here to reset...</p>',
    }),
  }
)
const data = await res.json()
// { success: true, messageId: 'msg_...' }

Core API Endpoints

POST/v1/api/sendSend a transactional email immediately
POST/v1/api/send/batchSend to multiple recipients in one call
GET/v1/api/contactsList, search and filter contacts
POST/v1/api/contactsAdd or update a contact
DELETE/v1/api/contacts/:idRemove a contact (GDPR erasure)
GET/v1/api/analyticsPull send, open and click data
GET/v1/api/usageCheck sends remaining this cycle
POST/v1/webhooks/endpointsRegister a webhook endpoint
Full API reference with examples →

Everything Included With the API

🔑

Sandbox key on signup

Test in a fully isolated sandbox environment. No DNS changes needed. Switch to production with one key rotation.

🪝

Webhooks for every event

Receive signed webhook calls for sent, delivered, opened, clicked, bounced and complained. Register up to 10 endpoints per account.

🚫

Suppression enforcement

The API checks your suppression list before every send. Unsubscribed and hard-bounced addresses are rejected at the API level, not just filtered.

📊

Per-send analytics

Query open rates, click rates and bounce rates per message ID via the analytics API. No dashboard login required.

🛡️

GDPR-compliant by default

GDPR-focused infrastructure operated under EU law. Suppression enforced. DSAR (erasure) endpoint included. DPA available on request.

Rate limiting by plan

API calls are rate-limited to match your plan's send quota. The usage endpoint lets you check remaining sends programmatically.

API Questions Answered

What is a transactional email API?+
A transactional email API lets your application send emails programmatically — things like password resets, order confirmations, welcome emails and notification alerts — triggered by user actions rather than scheduled campaigns.
How do I get started with the NexusProMail API?+
Sign up for a free account and your sandbox API key is ready immediately. No credit card required. The sandbox gives you 1,000 free sends to test with before going live.
What languages does NexusProMail support?+
The REST API works with any language that can make HTTP requests. We provide code examples for Node.js, Python and PHP, plus Postman collection for testing.
Does the API support webhooks?+
Yes. You can register webhook endpoints to receive real-time events for opens, clicks, bounces, complaints and unsubscribes. Webhooks are signed so you can verify authenticity.
What is the difference between transactional and marketing email in NexusProMail?+
Transactional emails (via API) are one-to-one messages triggered by user actions. Marketing emails are bulk campaigns sent to contact lists. NexusProMail supports both from the same account and the same sending domain.
Is the API GDPR-compliant?+
Yes. The API enforces suppression lists automatically — if a contact has unsubscribed or is suppressed, the API will reject the send for that address. All data is processed under EU law. A DPA is available on request.

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Also read: API integration guide · Email deliverability · Domain warming · GDPR compliance