Ever wonder how it’s possible that we put a man on the moon over 50 years ago, and yet you still can’t seem to maintain a clear phone call today? Yeah, same.

The natural reaction for many of us is to blame the stupid internet for being slow—but in the majority of cases, internet bandwidth is not the problem.

The truth is, for a crystal clear VoIP calling experience, you only need a bandwidth of around 0.15 megabits per second. 

Meanwhile, even the lowest-tier internet plans for homes and businesses generally supply speeds of at least 3 mbps—which is 20 times faster than the requisite 0.15 mbps.

Clearly, something else is the culprit for your choppy calls.

VoIP Bandwidth Requirements in Detail

In order to understand the bigger picture of how bandwidth affects VoIP calls, it’s important to take a closer look at how the calling process works.

What Is Bandwidth?

Technically speaking, bandwidth differs from internet speed, since it’s strictly a measure of how much data can be transferred through your internet system in a given period of time—assuming the system is working flawlessly. Speed, on the other hand, is a measure of how fast the data is actually transferred, given the current working condition of the system.

Practically speaking, internet calling data gets transferred by way of codecs. Codecs can be hardware or software-based, but their function is the same either way—they compress audio and/or voice data to make it more efficient for transmission, and then once the data has been transferred to the other end of the call, they decompress it again.

Codecs can significantly affect call quality. Higher compression leads to fast transfer times with reduced audio quality, whereas lower compression causes slower transfer times with better quality.

Specific Bandwidth Requirements

Since voice calling involves both transmitting and receiving data, you’ll usually want the same minimum bandwidth for both uploads and downloads.

Calculating the necessary bandwidth is a matter of simple arithmetic. Since you need 0.15 mbps for a single call, then a small business with 10 employees should scale that up to 1.5 mbps. Likewise, an enterprise with 100 employees working in the same office building should aim for 15 mbps just for calls.

That said, no one wants to run the risk of maxing out their total available bandwidth. Standard practice for both business and home internet is to calculate how much bandwidth is needed at maximum usage, and then add a 20-30% safety margin on top of that, just in case.

Finally, for the most accurate bandwidth estimate, it helps to check the requirements listed for your specific device, whether it’s a mobile phone or even a softphone application on a desktop computer. For example, a softphone used for video conferencing will require a bandwidth of around 3 mbps, compared to the only 0.15 mbps required by most audio-based VoIP providers.

How Do You Know How Much Bandwidth You Have?

By far, the easiest and fastest way to check your available bandwidth is to run a VoIP speed test. These can be as simple as clicking a button and then waiting around 30 seconds for your results.

Perhaps the most accurate way to test your full bandwidth potential is by checking directly with your internet service provider (ISP). Nowadays most providers will have a dedicated app or internet portal where you can check your current and total potential bandwidth, or run a specific VoIP quality test.

One of the benefits to checking current available bandwidth (which you might call internet speed) as opposed to total potential bandwidth, is that you’ll get an accurate picture of how much bandwidth is actually available for use at a given moment rather than an arbitrary, best-case scenario number.

It’s important to remember that any network activity—including employees scrolling through moon landing TikToks in the bathroom—will decrease the remaining bandwidth available for VoIP calls. This is another reason why a 20-30% safety margin on top of maximum foreseeable bandwidth needs is essential for any internet system.

For Most Businesses, Bandwidth Isn’t the Issue

Since almost every internet service plan includes more than enough bandwidth for VoIP calls, the problem with poor calling quality usually lies elsewhere.


Often referred to as ping or delay, latency is the time it takes for data to travel from you to the person you’re calling, and vice versa. High latency is the reason for those random lags in communication where people accidentally talk over each other, making conversations nearly impossible to hold naturally.

Packet Loss

With VoIP technology, data is transferred wirelessly in small units called packets. Packet loss is when these data packets don’t manage to reach their destination, for one reason or another. Quite obviously, this can lead to annoying gaps in conversation, making calls sound choppy and/or disjointed.


With VoIP calling, certain data packets can sometimes travel faster than others, resulting in janky audio that seems sped up or off-time. This is called jitter, and it’s one of the biggest culprits for unnatural-sounding conversation.

Quality of Service Settings

Generally speaking, internet connections can be adjusted to prioritize certain types of data transfer over others. If your internet quality of service settings don’t have VoIP data as the top priority, your calls might be breaking up even if you have plenty of bandwidth to go around.

Internet Service Provider Performance

Finally, if you cheaped out and went with the lowest-priced ISP in your area, there’s a chance your low-quality calls are due to outages and unreliable connections on the side of your bargain bin ISP.

When Bandwidth Requirements Could Be the Culprit

It may sound redundant, but bandwidth-related VoIP call quality issues can only happen when the usage exceeds total available bandwidth. Fortunately, this problem is usually pretty easy to identify.

High Concurrent Internet Usage

The most common scenario is when multiple employees or users are all using the internet at the same time. Sure, maybe your ISP provides you a bandwidth of 20 mbps and your VoIP call only needs 0.15 mbps, but that won’t matter if someone in the next room is streaming X-Men movies with Magneto and Wolverine in 4K.

Bad Cell Service

Another scenario where bandwidth requirements can cause problems is when you’re in low coverage areas and have little or no signal. In these situations—which are more frequent in remote working environments—choppy calls are usually the result of your VoIP requiring more bandwidth than what is currently available.

How To Stay Prepared

Inadequate bandwidth can sneak up on you, but there are a few things you can do to reduce the amount of times you get caught off guard.

  • Check your previous month’s usage history through your ISP in order to keep an eye on data trends and plan ahead for how much bandwidth you’ll need in the future.
  • If your data usage is nearing your current bandwidth limits, upgrade to a better plan so you can maintain a 20-30% buffer.
  • Consider doing what many large enterprises do, which is putting all VoIP phones on their own separate networks in order to eliminate congestion from non-VoIP sources.

Final Thoughts

While your bandwidth can sometimes be problematic if you’re dealing with high concurrent internet usage or abnormally slow cell service, choppy VoIP calls are usually caused by something else. Keep an eye on all the other factors in play before you start blaming your bandwidth.