There is no single answer across suppliers or configurations. Require an end-to-end data map covering the telephone provider, voice platform, model services, integrations, monitoring tools and your own systems.
Retell’s published data map illustrates an important distinction: disabling its persistent storage does not mean no data leaves the service. It states that webhooks can still carry transcripts and recording links, and that selected personal-information redaction occurs after the call. These are Retell-specific documented behaviours, not universal platform characteristics. (retellai.com)
Ask for this evidence:
| Data question | Required answer |
|---|---|
| What is processed? | Audio, text, identifiers, tool inputs, results and derived summaries. |
| Who receives it? | Named services and subprocessors for the chosen configuration. |
| Where does it persist? | Platform storage, webhooks, application logs, CRM and analytics copies. |
| How long is it retained? | Separate periods for each artefact, including backups and diagnostic logs. |
| Can it train models? | Contractual limits covering relevant providers and permitted exceptions. |
| Who can access it? | Roles, authentication, administrative access and support procedures. |
| How is it deleted? | Scope, timing, exceptions and evidence of deletion. |
| What changes after exit? | Export access, remaining copies and continuing obligations. |
Do not accept “zero retention”, “encrypted” or “US hosted” as complete answers to all eight questions. Have security reviewers test the promised configuration and reconcile it with the contract.