- Every email host advertises an uptime percentage.
- Here is what those numbers actually mean in hours of downtime, and what the SLA fine print usually leaves out.
Nearly every email hosting provider advertises "99.9% uptime" — but few explain what that guarantee actually covers, or what happens when it is missed. Understanding the real numbers helps you evaluate providers honestly.
What Uptime Percentages Mean in Practice
| Uptime | Downtime per year |
|---|---|
| 99% | ~3.65 days |
| 99.9% | ~8.76 hours |
| 99.95% | ~4.38 hours |
| 99.99% | ~52.6 minutes |
What SLAs Usually Do Not Cover
- Scheduled maintenance: often excluded from the uptime calculation entirely.
- Third-party outages: if your DNS provider or upstream connectivity fails, the email host may not count it against their number.
- Compensation is usually service credit, not cash: a percentage of your bill, not compensation for lost business.
- Claim process burden: many SLAs require the customer to actively file and document a claim within a tight window — a passive guarantee rarely pays out itself.
Questions Worth Asking a Provider
- Is the uptime figure measured for the whole platform or per account?
- Does scheduled maintenance count against the SLA?
- What is the actual claim process, and what is the compensation?
- Is there a public status page with historical incident records?
Reading a Provider's Public Status Page Correctly
A status page showing "all systems operational" today tells you almost nothing on its own — the useful information is in the incident history, usually accessible from the same page. Look specifically at how many incidents occurred over the past 6–12 months, how long each took to resolve, and whether the provider posted clear, timely updates during the incident rather than silence followed by a brief "resolved" note. A provider with a handful of well-documented, quickly resolved incidents is generally a stronger signal than one with a suspiciously spotless history, which sometimes simply means incidents were not disclosed rather than that none occurred.
Why Reliability Still Matters Beyond the SLA Number
A high SLA percentage on paper does not guarantee a good experience if outages, even brief ones, happen at predictable bad times (business hours in your timezone) or if support is slow to acknowledge issues. Check independent reviews and status page history, not just the marketed number.
Frequently Asked Questions
Is 99.9% uptime good enough for business email?
For most businesses, yes — under 9 hours of downtime per year is a reasonable, industry-standard baseline.
Should I choose a provider with 99.99% over 99.9%?
The practical difference is small in absolute hours; consider it alongside support quality and price rather than as the sole deciding factor.
Does an SLA guarantee compensation actually covers business losses from downtime?
Almost never — service credits typically refund a portion of your hosting fee, not the value of business disrupted during the outage, which is why choosing a genuinely reliable provider matters more than the compensation terms on paper.
Want email hosting with a transparent uptime record? See our business email plans or ask about our SLA.
How to Track Your Own Uptime Independently
Rather than relying solely on a provider's self-reported figure, a free third-party uptime monitoring tool (the same kind covered in our hosting monitoring guides) can be pointed at your webmail login page or a test mailbox's availability, giving you an independent record to compare against the provider's claims. This is particularly useful groundwork before any SLA claim conversation, since independent, timestamped data is far more persuasive than "it felt down" when discussing service credits with a provider.
