Yes. Soracom accounts incur no fees for simply existing, so you can maintain your account without cost even if you do not have any active SIMs or services. This allows you to easily register new SIMs or use services in the future without creating a new account.
To ensure you are not billed, please verify that all services are cancelled. For instructions, refer to the Canceling Services documentation.
If you do not intend to use your Soracom account for an extended period, we recommend enabling Multi-Factor Authentication for additional security.