I don't experience with Teams from an admin perspective but i have demo'd Webex calling. Nice system but phones are proprietary (ie cisco only no 3rd party phones), you will need a vendor to manage some aspect of it for you. I do like how easy it is to use and integrates with their conference service as well. Client is cross platform so Android/Windows/iOS have all the same look.

While I don't deal much on the sales side, so I have no clue on the pricing, make sure you compare both to the features you're expecting. WebEx (formerly webex teams) is missing a lot of features that were previously included with UC one (the app it's replacing) There is a roadmap plan for the next 2 years of all the features to be implemented, just not all are in there yet. Just something to keep in mind.

Disclosure: Enterprise VoIP Broker It really depends on your company's size, requirements & geography. For instance, if your company is mid-size or larger, in the US, or Canada, using Teams a ton, has E5 licensing, and basic feature requirements, then Teams Phone is a great option. Add any differentiation to the above sentence, and things start to change. Webex Cloud isn't one of my favorites, to compare to Teams, though. There are many other solutions that do a much better job for a non-Teams cloud PBX.

I have a myriad of VoIP systems at various businesses my company owns/operates. ShoreTel Sky (Mitel whatever), Vonage (eew), some weird hosted thing I have no control over (Zultys I think), On-Prem Call Manager with PRI's as well as SIP trunks, CenturyLink Hosted VoIP, and finally WebEx Calling. I have extensive experience with all of them, and I will say that by far WebEx calling has been the most reliable and easiest to manage. So much so that I am in the process of migrating every one of our sites to this service as contracts expire, etc. It is (weirdly, because Cisco) the most straightforward with respect to pricing, has call center features, a web-based receptionist client (operator console, whatever), integrates with Azure AD for SSO, and on. A couple weeks ago when most VoIP carriers in the country were having issues, WebEx Calling had none (that were reported to me). It is not perfect (none are), but I really recommend at least giving it a try.

Webex Calling still has more features than MS Teams Phone System. Webex Calling can be managed much easier than some of the MS Teams Phone System side that requires PowerShell commands for some items still. Webex Calling has REST API's available whereas MS Teams Phone System does not. Both have their own calling plans or do bring your own carrier. Webex Calling currently has more carrier options directly connected already. Webex Calling has Webex Contact Center you can easily add-on as well whereas Microsoft doesn't have a contact center and would have to be integrated separately. Webex Calling is cheaper than going E5 if not already on E5. Microsoft has abandoned every phone system/calling platform they've ever made so it's hard to see that they won't do the same thing again. Webex One (their big annual conference) is next week so it's worth joining to see the new Webex Calling features being announced.

Both platforms have their pros and cons, but the number one thing I can recommend is PICK JUST ONE. I have been involved with multiple entities that would use Webex for conferencing and Teams for chat/IM. Supporting several platforms and their licensing costs becomes very problematic with overlap in features.

Surprised no-one mentioned codecs on this thread so far. My companies want full capabilities, for both in the office and on the go telecommuting. MS Teams uses a mandated HD codec with a heavy payload so it doesn't fair well with low bandwidth situations and overhead jitter when used on victuals with softphones. IMO best to choose by cost and codec manipulation. No real worries with G.729 low bandwith and full quality, or the missing T.38 (g.711) Modem support as well.

I think the biggest driver would be whether you're already an O365 shop - if so, it makes little sense to not use MS Teams.

We're moving to Webex Cloud calling and chose it over MS Teams. The biggest issue we had with MS Teams, and most of us would have preferred to use them since we're an O365 shop, is that the sales team couldn't answer questions we had about reliability and uptime. It didn't give management the warmest of feelings.

I used WebEx Teams for some time and then changed to a company using MS Teams. I HONESTLY cant give you a big difference in the VOIP system. They seem similar, just a different GUI. All VOIP systems have occasional issues but I could not truthfully give you much more than that. Have not used MS Teams more than 3-4 months versus WebEx for years.

We evaluated Teams and Webex; planning to use the winner to both replace a traditional PBX telephone system, and also add messaging, collaboration, meetings and webinars. We do not already use O365 or other MS cloud products; everything is on prem. Ended up deploying Webex in April 2020, coinciding with covid lockdown. Happy with the choice. The overall feature set across Webex has everything we need, and users enjoy it. Cisco obviously has deep understanding of call centers, but using the Calling features as presented in Webex (without Cisco Call Center, or whatever that product area is called) was a little rough at first; has been improving along with the rest of Webex since we've been using it.

Did you consider Zoom Phone?

Something like Ring Central isn't an option? I like Ring Central a lot for VOIP. It also has video conferencing, etc, though their video doesn't support as many clients as Zoom/Google/Webex which drops my overall score.

Webex cloud calling support is crap. If you can manage without support, they won't be much different then any other system. If you have Teams, I would just use Teams because it will be cheaper and a lot less training. VOIP is VOIP, most of the SIP trunks go through a few providers. All of them will have issues at some point. Find something easy that works for the business, and you can tolerate supporting.

If all you care about is VoIP they're going to be about the same in terms of basic features: dial tone, basic call routing, voicemail, etc. are going to be practically the same for both. How about reliability? MS only promises 99.9% uptime, while Webex promises 99.99% uptime. This is the difference between 45 minutes and 5 minutes of downtime per month. Of course this depends on how reliable your Internet connection is for either service, but Webex offers a better SLA. Need endpoints other than softphones? Webex supports several Cisco handsets from simple 1 line IP/DECT phones to video phones with expansion modules and ATA adapters for analog. They also have a ton of desktop and room devices from 24" to dual 85" monsters. MS supports a handful of devices from several vendors, but if you have issues with them then you get to play the blame game between MS and the vendor. Meetings? I work with customers who use both Webex and MS Teams, and generally people are happier with the Webex Meeting experience. Webex has a lot more experience with online meetings than MS and I feel their interface is easier to use; I even use Webex to do video calls with family members because it's so easy to get them connected. Webex has thousands of 3rd party integrations, including integrations with MS products. Got Sharepoint/OneDrive? Webex can integrate just as well as MS Teams. Webex has better interop with other SIP services because they use industry standards instead of whatever MS did to their SIP stack.

My opinion is that it's 2021 and there should be a client that can work across all of these services similar to how Trillian worked back in the day.

Strictly meetings, use webex meet. Made the same mistake, was easier to get into a meeting with meet vs regular webex app.