SLA (service level agreement)

An SLA says what uptime the host promises, how it's measured, what's excluded, and what you get if it isn't met. The remedy is almost always a service credit, not a cash refund.

A service credit is a discount off a future bill, usually a percentage of the monthly charge for the affected service. Credits rarely cover more than that, and they never cover lost sales.

Example: a host's SLA promises 99.9% uptime a month, and your site is down for several hours one month. Under a typical SLA you'd get a percentage off the next bill for that service, but only if you claim within the deadline and the outage wasn't excluded, such as planned maintenance.

You usually have to claim the credit yourself, within a deadline, with your own evidence of the outage.

What it means for your price: a service credit is usually capped at what you pay for the service, so on cheap hosting it's worth very little. If downtime would cost you real money, weigh the host's track record and support more than the percentage in its SLA.

How to check yours: search the host's legal or terms pages for 'service level agreement'. Look for the uptime figure, the exclusions, the credit amount and how to claim.