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Last updated: 2026-03-16

What is SLA (Service Level Agreement)?

Definition

An SLA (Service Level Agreement) is a formal commitment from your hosting provider guaranteeing specific service levels, most commonly uptime (e.g., 99.9%). If the provider fails to meet these guarantees, customers typically receive service credits as compensation. SLAs set expectations and provide accountability.

Why It Matters

  • Defines the reliability you can expect from your host
  • Provides compensation when services fail to meet standards
  • Indicates provider confidence in their infrastructure
  • Critical for business continuity planning
  • Forms part of contractual obligations

How It Works

SLAs specify measurable targets (usually uptime percentage), measurement methods, exclusions (scheduled maintenance, customer errors), and remedies for failures (service credits). If a host promises 99.9% uptime but delivers 99.5%, customers can claim credits. Credits are typically a percentage of monthly fees, not cash refunds. You usually must request credits within a specified timeframe.

Pros & Cons

Advantages

  • Holds providers accountable for service quality
  • Provides financial compensation for outages
  • Indicates infrastructure quality
  • Sets clear expectations
  • Useful for business compliance requirements

Disadvantages

  • Credits rarely cover actual business losses
  • Many exclusions may apply
  • Claiming credits often requires documentation
  • Not all outages qualify for compensation
  • SLA percentages can be misleading

Common Misconceptions

  • !99.9% uptime means almost no downtime (Still allows 8.7 hours/year)
  • !SLA credits cover business losses (Usually just a percentage of hosting fees)
  • !All downtime is covered (Scheduled maintenance and many issues are excluded)
  • !Higher SLA always means better hosting (Marketing claims vs. actual performance)

Do You Need SLA (Service Level Agreement)? Checklist

Consider sla (service level agreement) if any of these apply to you:

  • You understand what the SLA guarantees (and excludes)
  • You know how to monitor and document outages
  • You understand the credit claim process
  • SLA uptime meets your business requirements
  • You've read the full SLA document, not just marketing claims
  • You have your own monitoring in place

Recommended Hosts for SLA (Service Level Agreement)

Kinsta

99.9% uptime SLA with transparent monitoring

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IONOS

99.99% uptime guarantee on premium plans

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SiteGround

99.9% uptime with proactive monitoring

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Frequently Asked Questions

What does 99.9% uptime really mean?
99.9% uptime allows 8 hours 45 minutes of downtime per year, or about 43 minutes per month. 99.99% allows only 52 minutes per year. 99.95% allows 4 hours 22 minutes per year. Each decimal point matters significantly.
How do I claim SLA credits?
Most hosts require you to open a support ticket within a specific timeframe (often 7-30 days) documenting the outage. You'll need evidence of the downtime and its impact. Credits are applied to future bills, not refunded as cash.
What is excluded from SLA calculations?
Common exclusions: scheduled maintenance, DDoS attacks, customer errors, third-party failures, DNS issues outside their control, and "acts of God." Read the full SLA document for complete exclusions.
Are SLA guarantees meaningful?
Quality hosts honour their SLAs and credits provide some accountability. However, credits rarely cover actual business losses from downtime. Use SLAs as one indicator of provider quality, but also check real-world reviews and independent monitoring.
How do I monitor uptime?
Use independent monitoring services like UptimeRobot (free), Pingdom, or StatusCake. They check your site regularly and alert you to outages. This provides evidence for SLA claims and helps you understand actual performance.
What SLA should I look for?
For business sites, 99.9% is the minimum standard. E-commerce and critical applications may need 99.95% or 99.99%. Remember: actual performance matters more than SLA numbers. Check independent reviews for real uptime data.
Can I negotiate SLA terms?
Standard shared hosting SLAs are non-negotiable. Enterprise and dedicated server customers may negotiate custom terms. VPS and cloud customers sometimes have options for enhanced SLAs at additional cost.

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