Email on Your Domain for Assistants: Security, Setup, and Benefits

Introduction

Business professionals increasingly rely on assistants to manage executive correspondence, scheduling, and client communication. Using email on your domain for assistants — rather than giving them access to an executive's personal account or relying on generic third-party addresses — strengthens security, preserves branding, and creates auditable delegation. This article outlines why domain-based assistant email matters, the security protections to apply, step-by-step setup guidance, operational best practices, and clear key takeaways for implementation.

Why use email on your domain for assistants?

There are multiple, business-driven reasons to host assistant email on your corporate domain rather than using personal or generic external accounts. Key benefits include stronger brand consistency, centralized policy enforcement, and clearer ownership of records for compliance and eDiscovery.

Benefits at a glance:

• Brand and trust: Messages sent from your domain carry your organization’s brand and are more recognizable to partners and clients.
• Security and deliverability: Proper DNS and authentication reduce spoofing and improve inbox placement.
• Governance and compliance: Domain accounts are easier to audit, retain, and include in discovery processes.
• Operational efficiency: Centralized account management speeds onboarding/offboarding and policy application.

Security: Threats and protections

Delegated assistant access introduces specific security considerations: credential compromise, accidental data exposure, and misuse of executive privileges. Mitigation requires layered controls that combine email authentication, identity protection, and access governance.

Core protections to implement:

1. Authentication protocols — implement SPF, DKIM, and DMARC on the domain to prevent spoofing and improve delivery (see RFC 7208 for SPF and RFC 6376 for DKIM; DMARC guidance is widely documented in industry sources).
2. Strong identity controls — require unique user accounts, enforce strong passwords or passkeys, and enable multi-factor authentication (MFA/2FA) for all assistant accounts.
3. Least privilege and delegation — avoid sharing executive credentials; instead use delegated mailbox access or role-based addresses with scoped permissions.
4. Monitoring and alerting — enable logging for mailbox access, set alerts for unusual sign-ins, and review sending patterns.
5. Device management — require device encryption, up-to-date OS/software, and mobile device management (MDM) for any device used to access corporate email.

Setup: Step-by-step guide for domain email provisioning

This section provides a practical, repeatable setup checklist for IT and security teams to provision domain email for assistants while minimizing risk and friction.

1. Decide account model
• Role-based address (e.g., assistant@company.com): good for shared access and human handoffs; consider mailbox delegation patterns and auditability.
• Individual assistant account with role label (e.g., jane.doe.assistant@company.com): better accountability and per-user MFA.
2. Choose an email hosting provider
• Select a provider that supports enterprise authentication, SSO, logging, and compliance features (e.g., major cloud email providers or secure hosted Exchange).
3. Configure DNS and authentication
1. Add appropriate MX records for the chosen provider.
2. Publish SPF records to authorize sending servers for the domain.
3. Deploy DKIM: generate keys via your provider and publish the public key in DNS.
4. Enforce DMARC with a monitoring policy (p=none) initially, then move to quarantine or reject as telemetry improves.
4. Provision accounts and access controls
• Create unique assistant accounts rather than sharing credentials.
• Apply role-based access controls (RBAC) and mailbox delegation instead of full credential sharing.
• Enable SSO integration with your identity provider and require MFA for all assistant access.
5. Document onboarding and offboarding
1. Include steps: account creation, device enrollment, security training, and confirmation of delegated mailbox permissions.
2. Offboarding must include immediate suspension of the assistant account, rotation of any shared secrets, and audit of mailbox activity if required.

Operational best practices

Operational controls reduce risk and keep assistant workflows efficient. These practices should be enforced via policy, automation, and periodic review.

Recommended operational checklist:

1. Least-privilege delegation — grant the minimum mailbox rights required (send-as vs send-on-behalf vs read-only).
2. Regular access reviews — schedule quarterly reviews to confirm which assistants still require access.
3. Audit and retention — ensure email retention policies meet regulatory needs and enable audit logs for access and message flow.
4. Incident response playbook — include steps to isolate compromised assistant accounts and notify stakeholders.
5. Training and phishing simulations — provide role-specific security training and run phishing exercises for assistants.

Key Takeaways

• Use domain-based email for assistants to preserve branding, improve deliverability, and centralize governance.
• Implement SPF, DKIM, and DMARC to reduce spoofing and phishing risk.
• Provision unique user accounts with SSO and MFA; avoid sharing executive credentials.
• Use role-based access controls and clear onboarding/offboarding workflows to reduce exposure.
• Regularly review access, retain logs for compliance, and maintain an incident response playbook.

Frequently Asked Questions

1. Should assistants use a shared mailbox or individual accounts?

Choose based on accountability and workflow: shared (role-based) mailboxes are convenient for handoffs but reduce auditability; individual accounts with delegated access preserve accountability and are recommended when tracking action and compliance matters. Implement RBAC and logging to mitigate risks with shared mailboxes.

2. How do SPF, DKIM, and DMARC work together?

SPF specifies which mail servers can send for your domain, DKIM adds a cryptographic signature to messages, and DMARC instructs receiving systems how to handle messages that fail SPF/DKIM checks. Together they significantly reduce spoofing and improve trust in your domain’s email (see RFC 7208 and RFC 6376 for technical details).

3. Can assistants access executive email without sharing passwords?

Yes — most enterprise email platforms support mailbox delegation or shared mailbox configurations where assistants are granted explicit permissions (read, send-on-behalf, or send-as) without needing the executive’s password. This supports auditing and avoids credential reuse.

4. What are the main compliance considerations?

Retention, eDiscovery, and access auditing are primary considerations. Ensure domain emails for assistants are included in retention policies, searchable for legal holds, and that logs capture who accessed or sent messages on behalf of an executive.

5. How should offboarding be handled for assistants?

Offboarding must be immediate and coordinated: disable or suspend the assistant account, revoke tokens and device access, reassign any delegated mailbox rights, rotate any shared credentials, and review recent activity. Document the process and automate where possible to reduce delays.