@Tim Braes , AFAIK, there is no defined SLA for Azure VNET. Azure Virtual Network is just a private IP block where all your resources can be deployed for private connectivity and secure those resources within a boundary. Virtual Network itself will never go down or experience outage, All the resources or services associated to the VNet may experience outage when a specific regional datacenter is down.
This is the reason there is no charge for using Azure VNet or data transfer within a VNet, it's free of cost. Standard charges are applicable for resources, such as Virtual Machines (VMs) and other services within VNET boundary. Hence, we don’t have any SLA for Vnet.
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