Is my network VoIP ready? How much bandwidth do I need?

VoIP calls typically require 24kbps to 90kbps of bandwidth (200kbps is ideal), but video calling and conferencing can require 3 to 20 times more bandwidth. While planning for your network, estimate how many simultaneous calls your organization expects to have at any given time and multiply those calls by 200 kbps.

Our average customer has about 10% of the organization on the phone at any given time. As an example, if you have 20 employees and anticipate 2 simultaneous calls at any given time, the network would ideally have 2*200kbps, or 400kbps of bandwidth dedicated to VoIP calls. Note that if your company heavily utilizes your network for bandwidth-intensive activities such as streaming video, you should account for that traffic as well. No need for a QoS device; we simply suggest you account for your bandwidth needs.

This VoIP Test is a general approximation of the quality of your VoIP connection. It does not test whether there are any active issues with your router that are impairing the quality of your connection.

Firewalls can complicate communications over a VoIP network. Firewalls sometimes perform Network Address Translation (NAT), a process OnSIP already takes care of with a “server-side” solution. We do not recommend disabling NAT traversal technologies, because of security concerns. But multiple NATs, SIP ALGs, SIP helpers, and any process that inspects packets can disrupt the quality of your call. We also do not recommend securing traffic by port range, but we do encourage users to open the router to our IP blocks for UDP traffic only, since the port for every call for audio will vary.

Download our full guide to VoIP readiness. 


How do I keep my existing telephone number?

OnSIP has extensive experience in porting phone numbers for a decade. Porting a number to OnSIP takes anywhere from 10 business days to 6 weeks, depending on your previous carrier. To begin the porting process, login to the OnSIP Admin Portal and select 'Port an outside number into OnSIP' under 'Phone Numbers'.

Check the portability of your phone number here. We try to work with all telephone service providers. However, certain local or regional guidelines may preclude your current provider from releasing your number.

Porting costs $15 per number. While you wait for your number to port, we can offer you a temporary OnSIP phone number to forward your calls to so your customers can still reach you at your existing phone number.


How do I get a new phone number?

We have phone numbers available for OnSIP customers in almost every region of the United States. An updated list of these numbers can be found on our phone number availability page. We also offer vanity numbers.


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How do I enable international calling?

OnSIP customers can make calls to anywhere in the world. Our standard calling area covers over 20 countries. To make calls to extended calling areas, you'll just need to submit an Extended Calling Area form. Here's how:

  1. Login to the OnSIP Admin Portal
  2. Click on 'Account' in the navigation
  3. Select 'Enable international dialing' under 'Support'
  4. Download and complete the form.
  5. Email the form to or fax it to 215.754.4477

Once we receive the completed form, we will enable all international calling on your account.


What phone should I use with OnSIP?

OnSIP is Bring-Your-Own-Device, meaning any standard SIP phone will work with our service. And unlike some VoIP providers, we don't lock phones with proprietary software. Visit OnSIP's Phone Central to read about VoIP phone reviews, phone promotions, and how to purchase new phones.  


What is your standard calling area?

OnSIP's standard calling area includes the lower 48 states in the US and 20+ countries. The standard calling rate is 2.9 cents per minute. All extension dialing and other internal calls are free!


How do I attend the Getting Started Webinar?

OnSIP hosts an interactive webinar every Thursday at 12pm ET / 9am PT for new customers and those who simply want to see how it all works. The webinar is about 30 minutes and is followed by Q&A. Click here to get a webinar invitation


Is your network VoIP ready?

Try our network test
Are there any contracts to sign or long-term commitments you’re not telling me about?

You can cancel at any time, without ever having to worry about penalties.


How does the 30-day free trial work?

If you decide to cancel your service within 30 days, you will not be charged for any of our hosted services (voicemail boxes, auto attendants, groups, etc).

Calls to and from the Public Switched Telephone Network are not included in the trial. We accept Visa, Mastercard, and American Express. Please have a valid billing address in the United States.


How many simultaneous calls will my OnSIP phone number support?

All of the phone numbers you get from us (both toll and toll-free) support unlimited simultaneous calls.

You’ll find that this is in stark contrast to competing services that advertise “unlimited inbound calling” but restrict their numbers to just a single call at a time. With OnSIP, your customers will never hear a busy signal.