Azure Load Balancer SKUs

Azure Load Balancer has two SKUs.

SKU comparison

Azure Load Balancer has 3 SKUs - Basic, Standard, and Gateway. Each SKU is catered towards a specific scenario and have differences in scale, features, and pricing.

To compare and understand the differences between Basic and Standard SKU, see the following table. For more information, see Azure Standard Load Balancer overview. For information on Gateway SKU - catered for third-party network virtual appliances (NVAs) currently in preview, see Gateway Load Balancer overview

Note

Microsoft recommends Standard load balancer. Standalone VMs, availability sets, and virtual machine scale sets can be connected to only one SKU, never both. Load balancer and the public IP address SKU must match when you use them with public IP addresses. Load balancer and public IP SKUs aren't mutable.

Standard Load Balancer Basic Load Balancer
Scenario Equipped for load-balancing network layer traffic when high performance and ultra-low latency is needed. Routes traffic within and across regions, and to availability zones for high resiliency. Equipped for small-scale applications that don't need high availability or redundancy. Not compatible with availability zones.
Backend type IP based, NIC based NIC based
Protocol TCP, UDP TCP, UDP
Frontend IP Configurations Supports up to 600 configurations Supports up to 200 configurations
Backend pool size Supports up to 1000 instances Supports up to 300 instances
Backend pool endpoints Any virtual machines or virtual machine scale sets in a single virtual network Virtual machines in a single availability set or virtual machine scale set
Health probes TCP, HTTP, HTTPS TCP, HTTP
Health probe down behavior TCP connections stay alive on an instance probe down and on all probes down. TCP connections stay alive on an instance probe down. All TCP connections end when all probes are down.
Availability Zones Zone-redundant and zonal frontends for inbound and outbound traffic Not available
Diagnostics Azure Monitor multi-dimensional metrics Not supported
HA Ports Available for Internal Load Balancer Not available
Secure by default Closed to inbound flows unless allowed by a network security group. Internal traffic from the virtual network to the internal load balancer is allowed. Open by default. Network security group optional.
Outbound Rules Declarative outbound NAT configuration Not available
TCP Reset on Idle Available on any rule Not available
Multiple front ends Inbound and outbound Inbound only
Management Operations Most operations < 30 seconds 60-90+ seconds typical
SLA 99.99% Not available
Global VNet Peering Support Standard ILB is supported via Global VNet Peering Not supported
NAT Gateway Support Both Standard ILB and Standard Public LB are supported via Nat Gateway Not supported
Private Link Support Standard ILB is supported via Private Link Not supported
Cross-regional load balancing (Preview) Standard Public LB is supported via Cross-region LB Not supported

For more information, see Load balancer limits. For Standard Load Balancer details, see overview, pricing, and SLA.

Limitations

  • You can upgrade Load Balancer SKUs.
  • A standalone virtual machine resource, availability set resource, or virtual machine scale set resource can reference one SKU, never both.
  • Move operations:
    • Resource group move operations (within same subscription) are supported for Standard Load Balancer and Standard Public IP.
    • Subscription group move operations are not supported for Standard Load Balancer and Standard Public IP resources.

Next steps