Hello @John P ,
Welcome to Microsoft Q&A Platform. Thank you for reaching out & hope you are doing well.
I understand that you would like to know if the Azure site to site traffic between Azure and your LAN is billable, and if yes, is it both ingress and egress.
As per Azure VPN gateway pricing page, we do charge for the VPN gateway that connects to on-premises and other virtual networks in Azure. This charge is based on the amount of time that gateway is provisioned and available. And data transfers over the VPN connections to your on-premises sites or the internet in general are charged separately at the regular data transfer rate. So yes, Azure site to site traffic between Azure and your LAN is billable and it is for egress only. Data Transfer In is free of charge.
Please refer : https://azure.microsoft.com/en-in/pricing/details/vpn-gateway/#faq
https://azure.microsoft.com/en-in/pricing/details/bandwidth/
Kindly let us know if the above helps or you need further assistance on this issue.
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