The cost of data transfer inside and outside Azure has become more and more complicated and confusing in recent years. This is due to various factors, so there are always new services with new prices, new Azure regions are emerging in more and more geographical zones and regular price updates are made by Microsoft. The graphic shown above is intended to clarify the costs for data transmission.
1 – Inside VNet
Data transfer within VNets is free of charge. This applies to services that are located in the same subnet as well as to the transmission from one subnet to another subnet within the same VNet.
2 – Datatransfer between Availabilty Zones
The data transfer between 2 Availability Zones, i.e. separate areas within an Azure Region, is currently free of charge. Services can be distributed to different areas of a region through the Availabitity Zone and are therefore located in different buildings with independent power supply and fire protection. Microsoft plans to charge costs for this data transfer from February 2021. Prices are currently not known.
3 – VNet Peering in the same Region
If data should be transmitted between 2 VNets, peering between the two VNets is required. Incoming and outgoing data traffic must be paid. Currently the price for inbound and outbound traffic in the same region is € 0.009 per GB. So if we transfer 1GB from
VNet-1 pays 0.009 € for the outgoing GB and
VNet-2 0.009 € for the incoming GB.
4 – VNet Peering in different Regions in the same Zone
If the two peering VNets are in different regions, the prices for global peering apply. It is relevant in which zones the regions with the VNets are located. The regions West Europe and North Europe can both be found in Zone 1. For Zone 1 the price is currently € 0.03 for each incoming and outgoing GB. Therefore if 1GB leaves
VNet-1 it costs € 0.03 and
VNet-3 pays € 0.03 for the incoming GB.
5 – VNet Peering in different Regions in different Zones
If the regions are in different zones, for example West Europe from Zone 1 and East Asia from Zone 2, the zone prices apply for the corresponding data flow direction. Currently, each incoming/outgoing GB in Zone 1 costs € 0.03. In Zone 2, each incoming/outgoing GB costs € 0.076. Therefore if 1GB leaves West Europe,
VNet-2 pays € 0.03 in peering costs. The costs for this incoming GB in
VNet-4 in East Asia costs € 0.076.
6 – incoming and outgoing Internet traffic
Incoming data traffic to an Azure region is free of charge. The price for outgoing traffic depends on the amount of data and differs again according to the respective zone. West Europe is in Zone 1, which defines a price of € 0.074 for each outgoing GB, but only if between 5GB and 10TB have been transferred so far.
If an Azure Region (West Europe) is accessed via the Internet from another Azure Region (North Europe), the corresponding outgoing costs must be paid. The corresponding answer from the North Europe region is also sent via the Internet and is therefore subject to a charge. VNet peering would be much cheaper.
7 – ExpressRoute in Service Provider Model
An ExpressRoute connects an on-premises location with an Azure region in various ways. Incoming data traffic is also free of charge here. The outgoing data traffic is again dependent on the respective zone. The outgoing data from West Europe to the on-premises location therefore cause a price of € 0.022 per GB.