Easy setup with 3CX hosted in the cloud and provides a cost effective Cloud phone system

Once it is setup which is really easy and great guides on the website it just works and we've had no issues.

Nothing really. Everything just works and we've had no issues

Overall experience has been good. The major thing I wish they had is a 24/7 phone number that I could pick up the phone and call for tech support. When we do cutovers and new projects it's usually done after hours or on a weekend to avoid cutting into business hours, so having support 24/7 would be hugely important to tech people like me.

Service is outstanding, don't have to deal much with dropped calls or latency issues. The web interface is intuitive and easy to use, and most importantly the support is pretty good (email/ticket only though, really wish they offered more support over phone)

I don't think they have phone support that you can call in normal, if they do please let me know and I'll modify this review. Only other drawback is cost is a tad higher than some others out there. But SIP.US is pretty easy and reliable.

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.

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?

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.