Disclosed are various examples for enrollment of gateway enrollment for Internet-of-Things (IoT) device management using a client device. In one example, an onboarding token is retrieved using a request for the onboarding token. The request is authenticated based on user credentials. A gateway account is created using a request to create the gateway account that is transmitted to the management service. The request to create the gateway account includes a gateway identifier. The request is authenticated based on the onboarding token. Gateway credentials for the gateway account are relayed from the management service to the gateway. The gateway credentials authenticate communications between the gateway and the management service. The gateway credentials are concealed from users of the client device.