Using SIP.US, I was able to lower my monthly phone costs by 10s of thousands of dollars per month.

I had poor results transitioning from POTS/ISDN to SIP with another provider. SIP.US made the port much simpler and handled the interaction with an uncooperative telco. The website management capability is outstanding. Updating e911 data as people move locations is as simple as entering the info and clicking SAVE. The support portal is easy to use and very responsive. Detailed billing is easy to view.

The one are that could be improved is notifications when you exceed trunk capacity. Rather than a notice that you exceeded it at some time in the past month, I'd like something closer to real-time notification with time/date to allow me to better adjust my trunk requirements.

When I happened across SIP.US in a google search on the weekend when our physical phone system crashed and we had to build a virtual one quickly and get it up and running before Monday, I had never used SIP trunks before. I had not used them because I was unsure of the technology and worried about call quality, the phone company always wanted to bring in a separate circuit to run SIP trunks (more bureaucracy and red tape). SIP.US was fast and easy to get going and JUST WORKS! We enjoy great call quality with SIP.US and have the flexibility to add and remove phone numbers and trunks at will. We can respond to market conditions instantly scaling up or down at will. I wish I would not have waited so long to give this service a try it really does change the way that we think about voice service. I suggest using the free trial and just giving it a shot, once you sign in and see the portal and all that you can do INSTANTLY you will be hooked.

SIP.US is very quick and easy to set up and use. I set it up at around 10pm on a weekend when our phone system had died and we had to recreate a virtual one that could not connect to our existing PRI. Without talking to anyone I had a SIP trunk up and taking calls in less than half an hour without having any previous SIP trunk experience. The next day (on a weekend!) I received a call from the executives at SIP.US to make sure I had everything that I needed. The support team proceeded to help us get all of our numbers ported as quickly as possible (you can do this from the web portal but they were just being nice.) Once I understood the ease of use (no calling and waiting for the phone company to wait through their bureaucracy), reliability and clarity of using SIP trunks through SIP.US I could no longer imagine relying on a traditional phone company for phone service. SIP.US is a game changer, we have never looked back. SIP.US is how phone service should be.

I have not found anything to dislike. SIP.US does what it says it is going to do and keeps on doing it. Full control of my phone service from a web browser, what's not to like?

I enabled sms feature I think from start on this year and I am unable to use till today, I have opened a ticket from that time and ticket is still open but no resolution. after weeks one line appear that we are working on it so I stopped asking and started a parallel service Ringcentral and in future we may move ourselves to Ringcentral coz nobody can wait for years.

Yes calls are working fine. we are using from multiple years and happy with call quality.

I enabled sms feature I think from start on this year and I am unable to use till today, I have opened a ticket from that time and ticket is still open but no resolution. after weeks one line appear that we are working on it so I stopped asking and started a parallel service Ringcentral and in future we may move ourselves to Ringcentral coz nobody can wait for years.

SIP.us allowed me to be operational on multiple platforms. Integration is simple, number selection is good, and implementation is fast. I had a client that needed to LNP 100 DID's and get services up quickly...SIP.us team had me up and working within 2 hours. The numbers were ported very quickly with no issues.

It's easy to use and it gets the job done. I've been using the service for over 4 years and it's been fantastic. I use it with X-Lite, Cisco CME, Kerio, Cisco phones converted to SIP, GrandStream, etc. The documentation around setup is easy to follow. I'm a consultant and i travel all over and i'm able to connect where ever i go.

I've had a few issues with address validation when setting up billing...but i made a phone call and support resolved it over the phone. I haven't had any issues with service.

Have been connected to SIP.US for many years. They've updated the web site to make it even friendlier and self-service is a snap. The only issues I've run into were local to my network & ISP but the support team was able to provide enough clues as to likely cause that I was able to get things up and running.

I have a home lab with a couple of Asterisk servers. Provisioning trunks & numbers is a breeze. I do contract work for businesses in London & Auckland and setting up a local DID is super helpful. Since my usage is quite variable I really appreciate the prepaid pay for what you use plans.

Haven'r run into any snags. I would appreciate SMS options for significantly less cost (although I haven't looked into this in a while).