Glossary · Monitoring

SLA (Service Level Agreement)

A service level agreement is a contract that promises a measurable level of service, such as 99.9% uptime, and defines the remedy when the provider misses it.

Updated October 5, 2026

A service level agreement (SLA) is a formal commitment between a provider and a customer that specifies what service level is promised, how it is measured and what happens if it is not met. Typically the remedy is a service credit, not a cash refund or damages.

Why it matters

An SLA tells you what a vendor will and will not stand behind. The fine print decides its value: the measurement window, what counts as downtime, excluded events and the claim process often matter more than the headline percentage.

Example

A typical clause: "Monthly uptime of 99.9%. If uptime falls below 99.9% but at or above 99.0%, the customer receives a credit of 10% of the monthly fee." At 99.9%, you allow roughly 43 minutes of downtime in a 30-day month. Exact tiers and credits differ by vendor, so read the actual contract.

Common mistakes

  • Assuming the SLA guarantees uptime. It only defines compensation when the target is missed.
  • Missing claim deadlines. Many SLAs require you to file within a limited number of days with evidence.
  • Not checking exclusions such as scheduled maintenance, customer-caused issues or force majeure.
  • Promising customers a stricter SLA than your own upstream providers give you, so you pay credits you cannot recover.

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