What Internet Uptime Guarantee Do I Need For Business VoIP?

Service uptime is a key factor when considering an Internet Service Provider (ISP). From a hosted VoIP perspective, a reliable internet connection is crucial for your phone system. Lower uptime guarantees mean more potential outages and service disruptions, which can completely cripple your ability to make and receive business calls.

The internet is the backbone of a hosted VoIP phone system. None of the other pieces (i.e. phones, routers, computers) will matter if your internet is not working. And not only that— the other services that hold your business together, not just your phone system, but payment processors, online booking registries, email, web browsers, and customer service interfaces, can all become inaccessible if your internet goes down.

A short internet disruption may be an inconvenience when you're sending an email to a co-worker, but for a call center or security company, even a few seconds of downtime can seriously disrupt business operations. Here's a quick FAQ guide on internet uptime for hosted VoIP.

What are uptime and downtime?

Uptime is the percentage of time that an ISP's internet service is active. Downtime refers to the percentage of time that an internet service is inactive. An ISP can experience both planned or unplanned downtime.

Planned downtime is anticipated by an ISP, and usually happens for technical and maintenance reasons. The ISP will alert all customers before these events occur so adequate preparations can be made. Unplanned downtime arises from an unforeseen event, such as a server failure, natural disaster, or anything that disrupts the network without authorization.

Internet uptime and downtime for hosted VoIP

How is uptime calculated?

uptime percentage = (days of uptime per year/365) * 100

Uptime is expressed as a percentage and is usually measured over a year, but it can be calculated in days, hours, minutes, or seconds as well.

How much internet downtime should I expect?

ISPs typically say that their services achieve uptimes in the range of 99%+. To hit that mark, an ISP must have at least 361.35 days of uptime per year.

Each successive 9 in the uptime percentage is often referred to as a "nine". For example, a 99.999% is marketed as "five nines", and is considered a gold standard in the industry.

With each successive "nine" in an uptime guarantee, there are significant differences in how much downtime a customer can expect. Here are two tables showing the amount of downtime you might experience on a yearly and monthly basis.

Downtime of 99%+ Services (Per Year)

Uptime % Days Hours Minutes Seconds
99% 3.65 87.6 5,256 315,360
99.9% 0.365 8.76 525.6 31,536
99.99% 0.0365 0.876 52.56 3,153.6
99.999% 0.00365 0.0876 5.256 315.36


Downtime of 99%+ Services (Per Month)

Uptime % Days Hours Minutes Seconds
99% 0.304 7.3 438 26,280
99.9% 0.0304 0.73 43.8 2,628
99.99% 0.00304 0.073 4.38 262.8
99.999% 0.000304 0.0073 0.438 26.28


What uptime guarantee do I need to run business VoIP?

The uptime guarantee that's right for your company depends on a number of factors. Mostly, your choice will rely on how integral the internet is to your everyday operations. Here are some questions that can help assess your business needs:

  • Do you have any critical operations that rely on the internet?
  • How does your internet connection impact your product or service delivery and performance?
  • What type of online activities do you need to support?
  • How do your customers reach you, and what is your support availability?

If you use a cloud phone system, internet uptime will have a serious impact on your business. Hosted VoIP requires an active internet connection to make inbound and outbound calls. All your business phone system features, including call queues, voicemail, and call forwarding, depend on an active internet connection. The same goes for all the other internet-based business services you employ. If your business relies heavily on the internet, you should aim to have at least a 99.999% uptime guarantee from your ISP.

To learn more about other business requirements for hosted VoIP, download our free eBook on Everything You Need for Hosted VoIP.

Download the free eBook: Everything You Need for a Hosted Phone System

What's an 'SLA'?

A Service Level Agreement (SLA) is the contract you enter with an ISP when you use its services. The SLA sets the ground rules for your internet service. The SLA expresses in writing the specific expectations of the service relationship, including a minimum uptime percentage that the ISP should meet.

If the ISP is not meeting the minimum uptime percentage, you can use the SLA to request better uptime. If the ISP still can't meet the uptime in the service agreement, you may have cause to opt out of the contract.

However, uptime "guarantees" are not binding. The ISP will not have to refund your money if it does not meet the agreed upon uptime percentage. Typically, ISPs will offer some credit for excessive downtime. Make sure to read the terms and conditions thoroughly to understand what scenarios are covered, and what you need to do in order to receive the compensation.

Woman reading service level agreement (SLA) for internet service

How can I track my internet uptime?

There are certain software solutions and browser plugins that can automatically monitor the responsiveness of your internet. Net Uptime Monitor and various apps from Paessler can track your internet connectivity 24 hours a day. This makes it much easier to see if your ISP is actually meeting the uptime guaranteed by the Service Level Agreement. You can use the data from these uptime logs to contest your internet service if needed.

Does '100 percent' uptime exist?

A few ISPs, especially large ones, claim that they offer 100 percent uptime guarantees. Some commentators have denied the possibility of 100 percent uptime for standard commercial purposes.

ISPs are not immune to natural disasters, DDOS attacks, hackers, and any number of technical issues that can cause hiccups in the service. Due to these variables and more, it is highly unlikely that an ISP can offer true 100% uptime.

Internet Uptime: Keep Your Business Running

When choosing an internet provider, it's important to take into account service uptime in addition to other factors, such as network bandwidth, connectivity, technical features, and cost. The better the uptime guarantee, the less you should have to worry about losing access to critical services and online portals.

Internet uptime is key for hosted VoIP phone services. Without reliable internet, your phone system is more likely to experience disruptions and leave you unable to communicate with customers and prospects. Getting "five nines" of uptime can be expensive, but your decision ultimately rests with how important uninterrupted internet access is to your business.

Topics: SMB Leadership, voip test, ISP, uptime