Managed Mail Relay Service

Secure, sovereign outbound email relay on UK infrastructure

Managed Mail Relay Service

Defended Solutions provides a hosted, highly available outbound email relay platform for organisations that cannot or should not route automated email through internal or customer-owned infrastructure. Built exclusively on UK-based, Defended Solutions-owned systems, the service ensures compliant, reliable email delivery with no dependency on AWS, Azure, Google Cloud, or any third-party provider, and no data leaving the United Kingdom.

Built for Sovereign Email Requirements

The Managed Mail Relay Service is designed for organisations whose software systems generate automated email, including meeting notifications, system alerts, and application-generated correspondence, where routing through a commercial provider or internal infrastructure is not viable or appropriate.

It is particularly relevant where:

  • Data sovereignty requirements prohibit the use of third-party relay services such as Microsoft 365, Google Workspace, or Mimecast

  • Network architecture or security policy prevents outbound email from traversing the public internet via commercial platforms

  • Procurement or compliance obligations require all email infrastructure to be hosted on UK sovereign systems

  • An existing internal mail relay is being decommissioned or is unavailable in a new environment

Choosing the Right Mail Relay for Sovereign Environments

Many organisations handling sensitive or operationally critical data already rely on commercial mail relay services such as Microsoft 365, Google Workspace, or Mimecast for their standard email needs. Where sovereign requirements apply, however, these platforms present challenges that are difficult to mitigate: data processed outside UK jurisdiction, infrastructure owned and operated by foreign-headquartered providers, and limited visibility into where email content traverses.

The Defended Solutions Managed Mail Relay Service is built specifically for environments where those constraints are not acceptable.

FEATURE STANDARD COMMERCIAL RELAY SELF-HOSTED RELAY DEFENDED SOLUTIONS MANAGED RELAY
Infrastructure Ownership Third-party provider Customer-owned Defended Solutions-owned
Data Residency Global or Regional Varies Strictly UK-Based
Sovereignty None Partial Full UK Sovereign
DNS Management (SPF, DKIM, DMARC) Self-managed Self-managed Managed by Defended Solutions
High Availability Provider-dependent Customer-managed Multi-location, automated failover
Encryption in Transit Varies Customer-managed TLS 1.2+ enforced
Third-Party Cloud Dependency Yes No No
24/7 Monitoring Provider-dependent Customer-managed Included
Suitable for UK Sovereign Requirements No Potentially Yes

Organisations requiring a needs analysis or further technical detail prior to procurement are welcome to contact Defended Solutions directly. All enquiries are handled in confidence.

What’s Included with Sovereign Mail Relay Services

The Managed Mail Relay Service is delivered on Defended Solutions-owned UK infrastructure and managed end to end by the Defended Solutions team. The following capabilities are included as standard across all service tiers.

UK Sovereign Infrastructure

All relay nodes owned and operated by Defended Solutions on UK-based systems, with no dependency on AWS, Azure, or Google Cloud.

High Availability

Multi-location deployment across UK data centres with automated failover, ensuring continuous email delivery with no single point of failure.

Encrypted in Transit

TLS 1.2 or higher enforced on all SMTP submission connections. Older protocols are rejected as standard.

Dedicated Relay Configuration

Each customer receives a dedicated relay endpoint with no shared sending pools or cross-customer routing.

DNS Record Management

SPF, DKIM, and DMARC configuration managed by Defended Solutions, reducing spoofing and impersonation risk.

24/7 Infrastructure Monitoring

Automated monitoring and alerting for relay health and delivery failures, with incident response managed by the Defended Solutions service desk.

The service is available across three pricing tiers scaled by monthly email volume. Scroll down to view options or get in touch to discuss your requirements.

The Managed Mail Relay Service is available in three tiers, scaled by monthly outbound email volume. All tiers include the same infrastructure, security, and DNS configuration. Customers may upgrade between tiers at any point during the contract term with 30 days written notice.

Service Tiers

Tier 1
£100/month
ex. VAT
  • Up to 10,000 emails/month
  • £10.00 per 1,000 emails
  • 12-month contract
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Tier 3
£325/month
ex. VAT
  • Up to 50,000 emails/month
  • £6.50 per 1,000 emails
  • 12-month contract
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All prices exclude VAT. Usage above defined tier volumes is costed upon application.

Onboarding is delivered remotely and is included within all service tier fees. The process is designed to be completed within a half-day session and covers everything required to bring the service into production.

Getting Started

1

Requirements Capture

Confirmed sending domains, application SMTP configuration, and expected email volume.

2

Relay Configuration

Dedicated relay endpoint provisioned, with authentication credentials and connection details provided.

3

DNS Configuration

SPF, DKIM, and DMARC record values provided for implementation by the customer's DNS administrator.

4

Integration Testing

Relay connectivity confirmed and test email delivery validated end to end.

5

Handover

Service credentials, monitoring access, and escalation contacts delivered to the customer.

To discuss onboarding timelines or request a service overview, contact the Defended Solutions team directly.

Delivered on UK Sovereign Infrastructure

The Sovereign Mail Relay Service runs exclusively on Defended Solutions-owned UK systems, with no dependency on third-party cloud providers. The service is delivered in accordance with ISO 27001, ISO 9001, and Cyber Essentials Plus accreditations.

ISO 27001
ISO 9001
G-Cloud 14
Cyber Essentials Plus

All engagements are led by UK-resident, National Security Vetted (SC/DV) personnel.

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Contact us about Sovereign Mail Relay Services today