Bring your own IP (BYOIP) to Azure with Custom IP Prefix

When you want to move to Azure, but you want to retain your current public IP addresses, because of IP whitelisting, or te preserve your established IP reputation, you can now move your Public IPv4 Addresses to Azure. Once onboarded, these IPs can be associated with Azure resources, interact with private IPs and VNETs within Azure’s network, and reach external destinations by egressing from Microsoft’s Wide Area Network

Onboarding your ranges to Azure can be done through the Azure portal, Azure PowerShell, Azure CLI, or by using Azure Resource Manager (ARM) templates. In order to bring a public IP range to use on Azure, you must own and have registered the range with a Routing Internet Registry such as ARIN or RIPE. When bringing an IP range to use on Azure, it remains under your ownership, but Microsoft is permitted to advertise it from our Wide Area Network (WAN). When you create a Custom IP Prefix resource for your IP range, Microsoft performs validation steps to verify your ownership of the range and its association with your Azure subscription. Each onboarded range is associated with an Azure region.

Important notes:

• The ability to bring your own IP addresses (BYOIP) to Azure is currently available in all regions.
• The minimum size of an onboarded range is /24 (256 IP addresses).
• Onboarded IPs are put in a Custom IP Prefix resource for management, from which Public IP Prefixes can be derived and utilized across subscriptions.
• You are not charged for the hosting or management of onboarded ranges brought to Azure.

More information: Bring your own IP addresses (BYOIP) to Azure with Custom IP Prefix | Azure Blog and Updates | Microsoft Azure