How to use a SIP Phone with Google Voice

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Google Voice is a great service that allows users to receive a free phone number and easily send or receive calls through the Google Gmail program. However, many users are looking to expand the service’s range, and make calls using their VoIP phones and internet service. Google is not a telephone company, however, so Google Voice calls are typically routed through existing landline or cellphone plans. Fortunately, there are ways to use Google Voice with VoIP calling.

What to Avoid

There are many third-party applications that have worked with Google Voice to send and receive calls through the internet (VoIP). These applications use open messaging protocol XMPP through Google Talk. However, Google has announced that it is disabling the XMPP messaging standard on May 15, 2014. There have been concerns about spam and industry support, and likely concerns about security and the revenue that third-party developers could make off the system. As a result, many popular applications that have been written about extensively will no longer work, including Simonetics, Talkatone, and GrooVe IP.

In addition, several sites claim to provide completely free VoIP calling through Google voice. Unfortunately, these sites are low-quality, not reliable, and often unethical. As a business user of Google voice, it’s important to find a quality low-cost provider.

How to Set Up a SIP Phone to Use Google Voice

To set up Google Voice to make calls with a SIP phone, here are the steps:

1) Add your VoIP phone number to your list of forwarding phones here:

2) Inbound calls to your Google Voice number will now ring to your VoIP phone, allowing you to answer with that device.

3) If you VoIP ISTP allows spoofing caller ID on verified phone numbers for outbound calls, you can cause outbound calls from your VoIP phone to appear to be coming from Google Voice. This way, your Google Voice number is the number that callers see and will respond to.

4) If you VoIP ISTP doesn’t have caller ID spoofing, consider getting a number from a service such as Callcentric. Add that to your list of forwarding phones instead of your original VoIP number, and provision your VoIP phone with the new number. If that isn’t possible on your VoIP device, you may want to purchase an Obi device and use that instead of your current SIP phone.

5) This setup allows you to send and receive calls using your SIP phone or device, and allows you to use important Google Voice features such as number blocking and voicemail over email.


Benefits to Using Google Voice with a SIP Phone

There are many benefits to using Google Voice with your SIP phone. First, you will have access to incoming calls on multiple devices, and you can configure which phones ring for incoming calls. The number isn’t dependent on which device you have, which gives your business a lot of flexibility.

In addition, Google Voice gives you the ability to configure how and when calls flow to other phone numbers. You can route calls to a work number during business hours, and a different number during off hours. You can also have customized ring tones and voicemail greetings depending on who the caller is. This gives your business an amazing ability to deliver a personalized touch to key clients.

Google Voice also provides the capability to screen callers, so that they have to state their name before you decide whether or not to answer. This can boost productivity and help you screen unwanted calls, even if caller id says “unknown number”. You can block particular callers, and receive voicemail via email.

All of these features of Google Voice work seamlessly with the benefits you gain from VoIP telephone service when you are able to link Google Voice and your SIP phone. You are able to get the best of all worlds, and handle your business calls and voicemails according to any preference.

Girl in Grass, Using a SIP Phone with Google

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Although recent changes to Google Voice have changed what applications are available to route Google Voice calls through SIP phones, it is still possible to use your Google Voice number and features in conjunction with your VoIP telephony. With a few simple steps, incoming and outgoing calls will use your Google Voice number, giving your business the benefits of the Google service along with the cost savings of VoIP telephony.