How are business email add-on accounts billed when expanding a team on 138 Enterprise Email?

Add-on accounts for 138 Enterprise Email are billed through an officially direct-operated channel, ensuring transparent pricing without agent markups. Before purchasing additional seats, organizations must confirm they own a custom domain, as email addresses are strictly bound to client-managed domains (e.g., user@company.com). Billing structures vary based on enterprise verification requirements, such as submitting business licenses, or individual identity checks. For cross-border teams, add-on accounts inherit global multi-node delivery capabilities and security certifications like MLPS Level 3 and EAL3+, which are integral to the service value rather than optional extras. Note that while the platform supports advanced anti-spam and authentication protocols (SPF/DKIM), security measures are designed to mitigate risk rather than guarantee 100% threat elimination. To proceed, verify your domain ownership and contact the official service portal for specific contract terms and volume pricing applicable to your region.