Understanding a Business Internet SLA Before You Sign

When comparing business internet plans, the SLA, service level agreement, is often reduced to a single figure in the brochure: 99%, 99.5%, 99.9%. The figures sound similar. The difference in lost working hours is not.

The SLA is the part of the contract that sets out what the provider promises, how it is measured, and what happens when the promise is broken. Reading it before signing is far easier than arguing about it after an outage.

Reading the availability figure

Availability states what share of the time the service is promised to run. The rest is downtime allowed without counting as a breach. Calculated for a 30-day month and a 365-day year:

The formula is simple: (100% minus the SLA figure) multiplied by the number of minutes in the period. A 30-day month has 43,200 minutes, so 0.5% of it is 216 minutes, or 3 hours 36 minutes.

Check the measurement period. 99.5% per year allows a single 40-hour outage without breach, while 99.5% per month does not. Also check whether availability is counted around the clock or only during business hours; the two give very different results for a business open in the evening.

Dedicated, broadband, and "up to"

An SLA figure only means something if you know what kind of service it covers.

• Dedicated internet means capacity reserved for you, with download and upload speeds that are usually symmetrical and guaranteed. 50 Mbps means 50 Mbps even at peak times.
• "Up to" broadband means the maximum speed under the best conditions. The line is shared with other customers, so speed can drop at busy times without counting as a fault.
• Business broadband sits in between: often faster support and an availability SLA, but the speed is still "up to".

On an "up to" plan, internet that is very slow but still up is often not counted as downtime. Ask whether the SLA also covers speed, latency, or packet loss, and how they are measured. The difference between plan types is covered further in the guide to choosing an internet plan for a business.

What doesn't count

The most important part of an SLA is often the exclusions list. Commonly left out of the calculation:

• Announced scheduled maintenance, check how long, how often, and at what hours it may happen.
• Outages due to force majeure such as natural disasters.
• Faults on the customer side: building power, customer-owned equipment, in-building cabling.
• Outages the customer did not report.

That last one is often missed. In many contracts, downtime only starts counting when the customer opens a ticket. A two-hour outage overnight reported in the morning may be recorded as much shorter.

Response time and restoration time

These two figures differ and matter as much as availability.

• Response time: how long until the provider acknowledges a report, for example 30 minutes. Acknowledging is not fixing; an automatic reply or a ticket number can satisfy this promise.
• Restoration time, often called MTTR (mean time to restore or repair): how long until service returns. Check whether this is a binding promise or merely a target, and whether it applies per outage or as an average.

The word "average" matters. An average MTTR of 4 hours still allows a single 10-hour outage if other outages are fixed quickly. A promise that "every outage is restored within 4 hours" is much stronger.

Also note support hours. 24-hour fault support differs from office-hours support, especially for businesses open at night or at weekends.

Compensation

Compensation, often called service credits or restitution, is almost always a bill credit: a percentage of the monthly fee per level of breach, with a cap, often no more than one month's fee. It usually has to be claimed, within a set time after the outage.

When reading the clause, look for:

• The tier table: for example availability just below the promise gives a small credit, rising step by step as availability falls further.
• The cap: the maximum share of the bill that can be credited in one period.
• Claim conditions: through which channel, with what evidence, and how many days after month end.
• Relation to other rights: whether the bill credit is stated to be the sole remedy.

So an SLA is not business insurance. An online shop that loses a day of sales will not receive that day's sales back. An SLA's value lies in the discipline it imposes on the provider, not the money that comes back.

Logging outages yourself as evidence

Claiming compensation is much easier with your own records, rather than relying only on the provider's.

1. Open a ticket every time an outage happens, promptly, through the official channel. Keep the ticket number and the time you reported it.
2. Record start and restore times on a simple sheet: date, time down, time restored, ticket number, symptoms, and what you checked on your side.
3. Make sure the fault isn't on your side. Check power, the equipment's indicator lights, and try connecting directly to the provider's device. The steps are in the guide to first steps when Wi-Fi is completely down.
4. Use automatic monitoring where possible. Many routers log WAN disconnections in their system log, and an external uptime monitoring service can alert you when the office IP address stops responding. This works best if you have a static IP.
5. Keep speed test results if the problem is slowness rather than an outage, with the time and device used, see the guide to checking internet speed.

At month end, compare your records with the provider's report. If they differ widely, records with ticket numbers make a far stronger case than memory.

Questions for the sales rep before signing

• Is it measured per month or per year, around the clock or business hours only?
• Is this service dedicated or "up to" broadband? Is speed guaranteed too?
• What are the exclusions, and how much scheduled maintenance is allowed?
• When does downtime start counting: when the ticket is opened, or when the provider's systems detect it?
• What response and restoration times are promised, and are they binding per outage?
• Does the link from the building to the provider's network have a redundant path, or is it a single cable?
• How is compensation claimed, and by when?
• What are the exit terms if breaches keep recurring?

Get the answers in writing, or make sure they appear in the SLA document. A sales rep's verbal promise does not help when claiming. The last point is often the most valuable: the right to end the contract without penalty after repeated breaches gives you a real choice. Contract termination in general is covered in the guide to cancelling a subscription and contract penalties.

Common mistakes

• Comparing figures without the period. 99.5% per year and 99.5% per month are not the same promise.
• Not opening a ticket. Unreported outages often never get recorded.
• Forgetting to claim. Many credits are not applied automatically and lapse after a deadline.
• Treating a high SLA as a substitute for backup. One cut cable still cuts one cable, however high the figure.

In short

Translate percentages into hours, read the exclusions, separate response time from restoration time, log outages yourself, and do not treat compensation as a replacement for losses. If the internet truly must not go down, a higher SLA is rarely enough, what you need is a backup connection from a different provider, as covered in the guide to backup internet for businesses.

Frequently asked questions