An SLA (Service Level Agreement) is the section of your contract that turns marketing claims into commitments. "Reliable, high-speed internet" means nothing in a dispute; "99.99% uptime with a 4-hour mean time to repair and service credits for misses" is enforceable. If a quote has no real SLA, you're buying best-effort service no matter what the salesperson says.
Uptime / Availability
This is the headline number, usually expressed as a percentage. It sounds abstract until you translate it into actual downtime per year:
- 99.9% ≈ 8.8 hours of downtime per year
- 99.99% ≈ 52 minutes per year
- 99.999% ("five nines") ≈ 5 minutes per year
The jump from 99.9% to 99.99% is large in practice. For a business where an hour offline is expensive, that difference is the whole point of paying for a dedicated circuit.
Mean Time to Repair (MTTR)
Uptime tells you how often things break; MTTR tells you how fast they get fixed. A strong SLA commits to a repair window — often 4 hours for dedicated services — versus the vague "next business day" typical of best-effort broadband. When you're down, MTTR is the number you'll care about most.
Ask directly: "What is your guaranteed mean time to repair, and does the clock start when I report the issue or when you acknowledge it?" The answer separates serious SLAs from decorative ones.
Latency, Jitter, and Packet Loss
For voice and video, raw speed matters less than consistency. Good SLAs commit to maximum latency (often well under 50ms on-net), low jitter, and minimal packet loss. If you run VoIP or heavy video, these targets matter more than another 100 Mbps of throughput.
Service Credits
This is what you actually receive when the carrier misses the SLA — usually a credit calculated from your monthly charge and the length of the outage. Read the formula. Some credits are token amounts that don't begin to cover the cost of being down, and many require you to request the credit within a set window or forfeit it.
The Fine Print That Undercuts SLAs
Watch for exclusions that quietly shrink the guarantee: scheduled maintenance windows, "force majeure," issues with your own equipment, and last-mile carve-outs. A 99.99% SLA with broad exclusions can be weaker than a 99.9% SLA with few. Always read what doesn't count as downtime.
Matching the SLA to the Site
Not every location needs five nines. A back-office might be fine on best-effort broadband, while your primary site, payment systems, or a clinic need a hard SLA. The right approach is to right-size: strong SLAs where downtime costs real money, lighter service where it doesn't. This is exactly the tradeoff dedicated internet access is built for, and where comparing carriers side by side pays off.
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