What are service-level agreements (SLAs)?

January 17, 2021

1 min read

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A service-level agreement (SLA) is a formal agreement between a service company and the customer. For Azure, this agreement defines the performance standards that Microsoft commits to for you, the customer.

Here’s a table to give you a sense of how total downtime decreases as the SLA percentage increases from 99 percent to 99.999 percent:

SLA percentage	Downtime per week	Downtime per month	Downtime per year
99	1.68 hours	7.2 hours	3.65 days
99.9	10.1 minutes	43.2 minutes	8.76 hours
99.95	5 minutes	21.6 minutes	4.38 hours
99.99	1.01 minutes	4.32 minutes	52.56 minutes
99.999	6 seconds	25.9 seconds	5.26 minutes

What are service credits?

A service credit is the percentage of the fees you paid that are credited back to you according to the claim approval process.

An SLA describes how Microsoft responds when an Azure service fails to perform to its specification. For example, you might receive a discount on your Azure bill as compensation when a service fails to perform according to its SLA.

Free products typically don’t have an SLA.

Azure status provides a global view of the health of Azure services and regions. If you suspect there’s an outage, this is often a good place to start your investigation.

SLA for Virtual Machines

For all Virtual Machines that have two or more instances deployed across two or more Availability Zones in the same Azure region, we guarantee you will have Virtual Machine Connectivity to at least one instance at least 99.99% of the time.
For all Virtual Machines that have two or more instances deployed in the same Availability Set, we guarantee you will have Virtual Machine Connectivity to at least one instance at least 99.95% of the time.
For any Single Instance Virtual Machine using premium storage for all Operating System Disks and Data Disks, we guarantee you will have Virtual Machine Connectivity of at least 99.9%.