How fast does my broadband need to be for VoIP?

Businesses and residential users are now moving away from traditional phone systems, replacing them with IP-based services such as SIP Trunks and Hosted PBXs. Whether it’s WhatsApp in your home or a Cloud-based PBX, the available bandwidth will determine how many concurrent calls you can make.

Please note: If you have other data usage on the network, you will need to factor this in.

Number of concurrent calls  Minimum required bandwidth Recommended speed
1 85 Kbps up and down 1 Mbps up and down
2 174 Kbps up and down 1 Mbps up and down
3 384 Kbps up and down 3 Mbps up and down
8 696 Kbps up and down 5 Mbps up and down
12 1 Mbps up and down 10 Mbps up and down

Your broadband speed requirement for VoIP depends on the number of concurrent calls you plan to use. The table above highlights the typical speed of using a dedicated broadband connection for voice. It’s important to note, that this is the speed required purely for voice usage.

Important considerations for VoIP

  1. What is my current broadband speed?
  2. What type of service does my ISP provide?
  3. What other services and applications on my network consume large chunks of bandwidth?

How do I check my broadband speed?

Many websites allow you to check your broadband speed. One that we would recommend is the dedicated speed test website www.speedtest.net.

Once you have arrived on the website, you must give consent and hit the “Go” button.

You will then receive three measurements.

  • Ping
  • Download
  • Upload

Please take note of both the download and upload speeds.

Calculating the bandwidth needed for VoIP

Once you’ve checked your broadband speed, it’s time to look at your Internet Service Provider (ISP). Some providers will promise a sustained speed, while others will provide an “up to” service.

  • When a provider can promise a sustained speed, setting 100Kpbs aside per line, will be sufficient for VoIP.
  • For a provider with no promised speed, setting a safety margin will be necessary. Eight concurrent calls would require 800Kbps (8 x 100 Kbps). It would then be wise to allow another 3Mbps (up and down). to allow for any drop-in service speed.

Monitor your network-wide bandwidth use

To track bandwidth usage across the network, this will need to be done at the router level. Most modern routers will have a traffic monitoring panel within the dashboard, login and see if you can find a tab labelled “monitoring” within the User interface (UI). Failing this, your ISP will most likely have a portal that can track your overall bandwidth use.