SLA (service level agreement)
An SLA is a service level agreement that sets out the quality of a service in measurable terms. Typical items are uptime, first response time and resolution time. It also says what happens if a promise is missed.
What is an SLA?
SLA stands for Service Level Agreement. Instead of a line like "we offer fast support", it contains measurable promises: what share of the month the system stays up, how many hours until someone responds to a fault, and the latest time it will be fixed.
Here is an everyday case. You sign up with a company to maintain your website. The SLA lists two kinds of time. First response time is how long until someone gets back to you after you report a problem. Resolution time is how long until the problem is fixed. An urgent case such as "the site is down" and a small request such as "fix a typo" are not handled in the same time. A good SLA sorts issues by priority and sets a time for each.
Why does it matter?
An SLA makes expectations clear from the start. 99.9 percent uptime sounds perfect, but in a 30-day month it still allows about 43 minutes of downtime. When you read the figures, check which hours are covered, whether planned maintenance counts and what happens if the promise is missed. When comparing offers, use the checklist in how to compare software quotes. We put support times in writing in our maintenance and support agreements.
Frequently asked questions
Are response time and resolution time the same?
No. Response time is how long until someone picks up the issue. Resolution time is how long until it is fixed. An SLA should state both separately.
How much downtime does 99.9 percent uptime allow?
About 43 minutes in a 30-day month. At 99 percent it is about 7 hours and 12 minutes in the same month.
Does a small business need an SLA?
It does not need a long legal document. But it should have in writing who to contact, through which channel, and how quickly an urgent issue gets a response.