Migrating Client Twilio Numbers to Agency Sub-Accounts for SaaS Rebilling

When onboarding new clients, you will frequently encounter businesses that already possess an independent Twilio account. While retaining their existing phone numbers is critical for business continuity, operating across separate client-owned accounts creates severe administrative friction. It prevents your agency from utilizing built-in SaaS rebilling features, forcing you to forfeit message markups and manage fragmented billing arrangements outside your primary dashboard.

The cleanest solution to this operational challenge is transferring the client's phone numbers directly into a new sub-account under your agency's master Twilio account. By consolidating telecom management under your parent structure, you regain central control over phone routing, streamline carrier compliance, and activate recurring revenue markups on SMS and telephony usage.

Creating the Dedicated Agency Sub-Account

Before initiating a transfer request with Twilio support, you must establish an isolated container for the client's assets within your master account. Operating individual sub-accounts for every location on your platform ensures strict isolation of usage metrics, webhooks, and billing limits.

1. Log into your primary agency Twilio console with administrator privileges.
2. Navigate to the Account menu or settings menu and select Sub-accounts.
3. Create a new sub-account, naming it clearly after the specific client or business entity.
4. Record the unique Account SID generated for this new sub-account, as this will serve as your Gaining Account SID during the transfer process.

Submitting the Dual Support Transfer Requests

Twilio enforces strict security protocols to prevent unauthorized number hijacking. Moving numbers between distinct parent accounts requires verified approval from both the losing entity and the gaining entity through concurrent support tickets.

You must collect the Losing Account SID from the client's existing setup. If their account is currently linked to HighLevel, this string can be located under Agency Settings within the Twilio management tab next to the location name.

Both parties must then submit explicit instructions to Twilio support detailing the transfer scope:

• Agency Ticket: Submit a request from your master account specifying the client name, losing account email, losing Account SID, gaining sub-account SID, and the exact phone numbers to be moved.
• Client Ticket: Have the client log into their independent Twilio console and submit a corresponding ticket confirming their authorization to release the exact same phone numbers to your account structure.

Relinking Credentials in HighLevel

Once Twilio support processes the internal transfer, the phone numbers will immediately populate inside your newly created agency sub-account. The final phase involves updating the platform integration so automated workflows and sub-account messaging hit the correct API endpoints.

1. Access the newly populated sub-account inside your master Twilio console to locate its specific Account SID and Auth Token.
2. Open your HighLevel agency dashboard and navigate to Agency Settings, followed by the Twilio or Phone Integration section.
3. Locate the target client account in the location list and select the option to modify or update API credentials.
4. Replace the legacy client-owned Account SID and Auth Token with the credentials belonging to your new agency sub-account.
5. Save the configuration and test inbound and outbound messaging from the location's conversations view.

Activating Rebilling and Operational Audits

With credentials successfully updated and numbers hosted under your primary agency architecture, automated usage rebilling can be toggled on within the agency SaaS settings. You can now apply custom multiplier rates to outgoing and incoming text messages, calls, and email services.

After completing the technical migration, perform a thorough operational audit to guarantee uninterrupted service:

• Verify A2P 10DLC Registration Status: Check whether trust center profiles and brand registrations need to be re-linked or resubmitted under the new sub-account container.
• Inspect Webhooks: Confirm that messaging URL handlers and status callback endpoints automatically re-pointed to platform infrastructure upon credential update.
• Confirm Auto-Top-Up Settings: Ensure your agency billing portal has adequate credit limits enabled to handle the consolidated messaging volume before client card rebilling processes.