Best Enterprise Phone System 2025

Looking for an enterprise phone system that balances cost, scalability, and functionality? After assessing the top VoIP phone systems for enterprises in 2025, RingCentral Ultra takes the top spot with unrivaled call management features such as custom call routing, industry-leading CRM integration options, and a full suite of communication tools from SMS to e-fax.

Zoom Regional Unlimited and Zoom Global Select offer some of the most cost-effective plans, with unlimited calling for just $15 and $20 per user per month, respectively. For international businesses, 8×8 Work leads the way, providing unlimited calling to 48 countries.

Of course, the best choice depends on your business needs. In this guide, we’ll break down the key strengths, weaknesses, and pricing details of each provider to help you find the right enterprise phone system for your company.

The Best Enterprise Phone Solutions in 2025

Before we get into each of our enterprise phone solution reviews, here is a topline comparison between our leading seven picks.

1. RingCentral Ultra: Best Enterprise Phone System Overall

Simply put, RingCentral Ultra is the best choice for large enterprises needing a fully integrated, feature-rich VoIP system.

It scored perfectly in our latest research of the top enterprise phone plans for categories including call management, software integrations, and communication channels. That’s down to offering features like advanced call routing, voicemail transcription, and an industry-leading number of CRM and helpdesk integrations. However, it isn’t the cheapest option out there. Here’s what you need to know at a glance.

Why do we recommend RingCentral Ultra for enterprises?

Earning a perfect score across several of our research criteria, there are plenty of reasons why RingCentral Ultra is well worth recommending to enterprises.

For starters, RingCentral Ultra leads the pack with call management features like customizable call routing, virtual receptionist, and call queuing. It has the native ability to add customizable hold music, too, for your monthly cost, unlike Ooma Office Pro Plus which requires you to buy an add-on. Zoom Global Select and Zoom Regional Unlimited also scored a maximum in this section, but they do lack RingCentral’s advanced analytics for calling data or integration with as wide of an extent of CRM platforms to store data.

Relatedly, RingCentral Ultra has superb training features for staff with call recording, call monitoring, call barging, call whisper, and analytics all included, whereas Ooma Office Pro Plus and GoTo Connect Phone System charge extra for some of these.

RingCentral Ultra also topped the scale with software integrations. CRMs like Salesforce, helpdesk tools, and calendars like Gmail and Outlook are all covered as part of RingCentral’s 300+ native app integrations. When looking at the competitors, we can see the likes of Vonage Advanced and Ooma Office Pro Plus lag behind with fewer supported platforms.

RingCentral Ultra has all major communication options too—team messaging, SMS, call conferencing, video conferencing, and e-fax. It’s worth noting that most provider plans listed here match RingCentral Ultra in channel extent, besides Zoom Global Select which lacks SMS and e-faxing abilities.

Add in strong security measures, 24/7 support, and uptime guarantees — all three of which most competitors supply, but still worth stating all the same — and we think RingCentral Ultra is a reliable choice for most enterprises, but especially large businesses handling high call volumes and with complex internal communication requirements.

What could be improved about RingCentral Ultra for enterprise businesses?

A potential key issue for enterprises will be RingCentral Ultra’s higher cost per user compared to some of the competition. At $35 per user, per month, it is more expensive than Ooma Office Pro Plus ($29.95) and Zoom Regional Unlimited ($15), which might be better for businesses prioritizing affordability.

We’d argue that you get significantly more robust integrations and features for the money than both of Zoom’s phone plans. Ultimately, RingCentral Ultra may just be outside your budget or not worth risking if you are a cost-sensitive enterprise.

Elsewhere, you could find wider hardware compatibility with alternative providers. We found that RingCentral-certified devices are fewer compared to Vonage and GoTo Connect, though this may vary depending on the specific desk phone brands you need. It’s also worth mentioning that you don’t necessarily need any hardware since all providers on this page have desktop and mobile apps to use for calling instead.

2. 8×8 Work: Best for International Enterprise Communications

For large enterprises with international operations, we strongly believe you have no better choice than 8×8 Work.

Bringing unlimited calling to 48 countries to the table, and closely competing with RingCentral Ultra in areas like call management and integrations, companies with a global customer base will be well served by its comprehensive offering. Here’s why it may (or may not) be the enterprise phone system for your team.

Why do we recommend 8×8 Work for enterprises?

Where 8×8 Work shines brightest is global reach. With unlimited international calling to up to 48 countries, it is ideal for businesses with international clients.

Most other providers, like RingCentral Ultra and Zoom Regional Unlimited, focus on domestic markets and require you to either pay a per-minute rate for overseas calls or purchase an add-on per month for unlimited international minutes. With 8×8 Work, you’ll have this international outlook, and all associated costs, already baked in.

It’s also a solid contender for your enterprise phone system in other ways, too. 8×8 Work has extensive communication channels, bettering both Zoom plans which lack e-fax, and the Global Select plan specifically which also doesn’t allow for SMS abilities.

Tied with RingCentral, 8×8 Work offers comprehensive software integrations with major CRM platforms like Salesforce, Zendesk, and HubSpot. Unlike Ooma Office Pro Plus, 8×8 Work doesn’t limit integrations to paid add-ons, either.

As with most provider plans on this page, you have all the communication channels we looked for as part of 8×8 Work’s package, including SMS, e-fax, and call conferencing. Notably, 8×8 Work allows for up to 200 participants per video conferencing meeting, which is the second highest after Zoom’s 500-participant maximum.

What could be improved about 8×8 Work for enterprise businesses?

8×8 Work is slightly behind all other provider plans on this page for call management features, though that’s only because each of our top seven were high scorers in this area. 8×8 Work only misses out on voicemail/automatic screening tools, which is the only difference between its calling features and the alternatives, according to our research. In other words, unless this is a necessity, you might not notice this lacking. But it is a missing feature all the same.

8×8 Work also supports fewer hardware brands than GoTo Connect, Vonage, or RingCentral, only linking up with four desk phone brands we tested.

A final, key difficulty with 8×8 Work is that it uses private pricing. We can’t be sure of the exact costs you will face, since these will vary depending on the features you require and your user count. Still, this can be a benefit for large enterprises, since the more staff you have the cheaper price you could get, in contrast to Vonage Advanced’s flat $39.99 per user, per month price point, which is less flexible.

3. Zoom Regional Unlimited: Best Budget Enterprise Phone System

Zoom Regional Unlimited is the most cost-effective VoIP solution for large US-based enterprises, offering a strong balance of price, call management, and communication features.

As you might expect, it integrates seamlessly with Zoom’s video conferencing tools, making it a great internal communication tool for hybrid or remote teams. While also scoring highly for call handling and security, it lacks strong CRM integrations and advanced analytics, making it less suitable for sales and customer support operations. Read our quick summary below before diving into exactly what Zoom’s Regional Unlimited package offers.

Why do we recommend Zoom Regional Unlimited for enterprises?

At $15 per user, per month, the Zoom Regional Unlimited plan is the most cost-effective option for all business enterprises, ahead of Zoom Global Select ($20) and Ooma Office Pro Plus ($29.95). When you compare it to the pricing of RingCentral Ultra ($35) or Vonage Advanced ($39.99), the cost savings are clear.

But to illustrate my point, here’s a quick calculation for a 100-person organization. RingCentral Ultra will cost $42,000 per year ($3,500 × 12) while Zoom Regional Unlimited will cost just $18,000 per year ($1,500 × 12). That’s a potential saving of $24,000 per year.

For that lower price, what do you get? Zoom matches RingCentral Ultra for its widest extent of call management features, featuring a virtual receptionist, voicemail transcription, and custom routing. That’s the same functionality but at a fraction of the price.

It doesn’t match RingCentral Ultra’s extent of communication channels, however, since it lacks e-fax functionality. But all else is covered, including SMS messaging and team chat, so if your business doesn’t need this very specific tool you’ll still find Zoom has a wide array of comms options.

Especially since it offers seamless integration with Zoom Meetings to provide best-in-class video conferencing, with support for up to 500 participants per meeting, unmatched by all other competitors on this page. During video and voice calls you have nifty tools at your disposal too, such as giving reactions or making notes as seen below.

What could be improved about Zoom Regional Unlimited for enterprise businesses?

Where Zoom Regional Unlimited primarily falls short compared to the higher cost plans like RingCentral Ultra is in its analytics and CRM integrations. Far fewer CRM and helpdesk integrations than most competitor plans listed here means you’ll need to check whether the tools you use are fitted for use with Zoom Phone. If they aren’t, you can either look elsewhere (RingCentral or 8×8 have the widest options) or adapt to fit Zoom’s integration selection.

It’s also notable that Zoom doesn’t offer email-based customer support, nor could we find evidence that it caters to onboarding support. If you are a large team and don’t have the time to train all your staff this could be an inconvenience. You’ll find both with RingCentral Ultra, for instance.

4. Zoom Global Select: Best Enterprise Phone System for International Expansion

Should your team need to make phone calls as if you are located in a different country, then none of the enterprise phone systems is up to the task. Except one: Zoom Global Select.

The package allows you to pick a location for your unlimited calling outside of the US & Canada for a still affordable price of $20 per user. It maintains the vast majority of Zoom’s Regional Unlimited plan features, including the ability to use Zoom’s renowned video conferencing capabilities, but still sees it fall behind our top two for CRM integrations and analytics. Below is a summary of its features before we get into the specifics.

Why do we recommend Zoom Global Select for enterprises?

As stated above, what sets Zoom Global Select apart from the other phone system plans for enterprises is that you can opt for unlimited domestic calling in one of 49 countries outside of the US and Canada.

After picking your local country, you’ll receive local numbers to use so that you can call across the country’s local PTSN network. You can call from anywhere in the world without any additional costs. This betters all other plans since even 8×8 Work doesn’t allow this functionality.

Other than that, Zoom Global Select is almost identical to Zoom Regional Unlimited. You still have the largest amount of call management and training features out of the providers we’ve researched. That list includes call whisper, monitoring, and barge functions that are missing from Ooma Office Pro Plus.

It also supports up to 500 participants per video call, matching RingCentral Ultra and exceeding 8×8 Work (200 participants), as part of a sleek interface that we found very simple to use in our testing of the Zoom One platform. For large businesses with staff numbering in the several hundreds, this could be crucial functionality so that you can all remain on the same page, rather than have to split off into separate calls.

And, while a little more than the Regional Unlimited plan ($15), Zoom Global Select is still just $20 per user. That’s far cheaper than the likes of Vonage Advanced ($39.99).

What could be improved about Zoom Global Select for enterprise businesses?

What is different about Zoom Global Select to the Regional Unlimited plan is that, while you still have communication features for channels like team chat and video calling, you lose out on included SMS capabilities for the majority of nations. Unlike RingCentral Ultra and 8×8 Work, which both support e-fax, neither of the Zoom plans support e-faxing.

It is also worth stressing that, while you’ll have unlimited calling in the country of your choosing, calls from that country to others will be subject to variable rates. If you want to have unlimited calling to multiple countries at once rather than have a local phone number abroad, we suggest  8×8 Work’s unlimited international calling to up to 48 countries. If getting Zoom is a must, you can purchase an unlimited international calling add-on to up to 19 countries.

As discussed with Zoom Regional Unlimited, the Zoom platform also has fewer analytics and CRM integration tools to play with compared to RingCentral Ultra or 8×8 Work (although, the likes of Salesforce and HubSpot are covered if you have a big-name integration you need covered). Similarly, there’s a lack of onboarding support, which might be an issue for big teams.

5. Vonage Advanced: Best Enterprise Phone System with Flexible Pricing

If you want a degree of flexibility with your phone system, Vonage Advanced is a strong enterprise phone system.

Fitted with appealing internal communications and CRM integrations, it provides customizable plans that should make it appealing to businesses that don’t want to pay for features they don’t need. However, it does fall a little short in customer support and pricing, as its $39.99 per user plan is the most expensive among major competitors. Here’s what else you should consider in short.

Why do we recommend Vonage Advanced for enterprises?

Compared to its competitors, Vonage Advanced has several appealing characteristics. Our research found it offers reliable call management, tied with all the other top-ranking providers, with customizable call routing and voicemail included by default.

You’ve also got a complete communication suite that includes team messaging, SMS, and call conferencing, as well as a full set of training tools to upskill staff as you coach using monitoring or barging features.

If any of these features aren’t to your liking, opting for its Vonage Advanced plan, the provider allows you to customize the package how you see fit. While some providers allow degrees of customization, for instance, GoTo Connect Phone System and its international calling allowance, the extent offered by Vonage is unrivaled.

What could be improved about Vonage Advanced for enterprise businesses?

At $39.99 per user, per month, Vonage Advanced is one of the most expensive options we researched, especially when compared to either Zoom plan ($15 to $20) or Ooma Office Pro Plus ($29.95).

Vonage also scored the second lowest in our assessment of both software integrations – comparable helpdesk integrations to most plans, but with fewer CRM platform options, no Microsoft Teams integrations and no third-party customer live chat tool integrations – and hardware integrations – just three desk phone brands – of the plans on this page.

6. Ooma Office Pro Plus: Best Enterprise Phone System for Affordable Simplicity

Ooma Office Pro Plus is an excellent choice for enterprises that prioritize ease of use and straightforward call management in an affordable phone system.

Unlike RingCentral Ultra or 8×8 Work, which require extensive customization and onboarding, Ooma offers a streamlined setup with minimal IT involvement. While it doesn’t have the most advanced integrations or widest communication channels, it remains a strong option for enterprises that need a no-fuss, reliable phone system with core VoIP features at an affordable price point.

Why do we recommend Ooma Office Pro Plus for enterprises?

One of the major plus points of Ooma Office Pro Plus from our testing of its software, was how easy to use it is. One participant said: “The thing I enjoyed the most was the simplicity of it. I’ve not used VoIP software before, but I managed to complete all the [user testing] tasks pretty easily.”

We were similarly impressed with how call notifications were clear, with large answer buttons, as well as Ooma’s smooth Google Calendar integration ready to use and access in less than one minute. Plus, we found general setup is simple, compared to the feature-heavy RingCentral Ultra or 8×8 Work, making it suitable for businesses without dedicated IT teams.

That’s down to a more streamlined set of training features and integration options, as we’ll come to, but all the call management and communication channels we looked for are present and correct from call flipping and forwarding to video conferencing, SMS and e-fax.

A small critique about video conferencing would be that our testers found that they could not invite colleagues directly from the platform meeting video meeting and had to send external links. But other than everything worked as we wanted it to, with the in-call interface looking as follows.

Perhaps most important of all, at least when it comes to your bottom line, a monthly cost of $29.95 per user makes Ooma Office Pro Plus an affordable choice for most enterprises. Only the Zoom plans are cheaper than the packages on this page.

What could be improved about Ooma Office Pro Plus for enterprise businesses?

Ooma Office Pro Plus is the only provider plan on this page to not receive perfect scoring for training features. While you receive call barge and call recording capabilities, you don’t get call barge features. You can get call monitoring and call analytics added to your package, but they come at an additional cost.

As such, we wouldn’t recommend this plan for businesses needing to regularly train new employees due to the absence of these coaching tools. You can get all these features included with RingCentral Ultra or either Zoom plan, all within your monthly cost. Plus, the analytics tools of RingCentral are also more advanced.

Ooma also has the worst hardware integration options of all plans on this page, according to our research, with only two desk phone brands being seamlessly compatible. This might vary depending on your required brand and model, so it’s worth checking with Ooma, but it could be an issue if you don’t.

Ooma offers fewer CRM integrations than other provider plans like RingCentral Ultra and 8×8 Work too. It still has middling software compatibility though, with major software like Salesforce and Microsoft Dynamics 365 covered for the most part, so again, your mileage may vary.

7. GoTo Connect Phone System: Best Enterprise Phone System for Hardware Compatibility

Balancing affordability, scalability, and call management features, GoTo Connect Phone System is a well-rounded enterprise VoIP solution.

It is particularly strong in hardware compatibility which makes it an excellent choice for enterprises transitioning from traditional PBX systems. However, compared to the top options on this page, it lacks strong CRM integrations and call analytics, making it less ideal for customer service-heavy businesses. Let’s look at GoTo’s Connect Phone System at a glance.

Why do we recommend GoTo Connect Phone System for enterprises?

Where GoTo Connect Phone System sits above all other providers on this page is for the range of hardware options its software is seamlessly compatible with. Integrating with well over 10 desk phone brands, it is far ahead of the next best (Zoom) in this category, making it a sure-fire pick if you have team members with a range of hardware devices working across variable locations.

While not as comprehensive as the likes of RingCentral Ultra or Zoom Regional Unlimited, GoTo Connect Phone System offers all essential call management features like call routing, call forwarding, and call screening. Plus, while stated to only be part of certain Phone System plans (and therefore we aren’t sure if this is included in your base monthly cost), GoTo also offers unlimited calling to up to 50 countries, beating out 8×8 Work’s potential reach if you opt for this package.

All training tools for coaching like whisper and barge are also in place. And, like almost all providers, you’ve got a full communication suite of team messaging, SMS, call conferencing, video conferencing, and e-fax to use, too. For a price of $26 per user, per month, that is pretty decent functionality in our book.

What could be improved about GoTo Connect Phone System for enterprise businesses?

While hardware integrations are a strong suit, GoTo Connect Phone System has among the worst software integration options of all provider plans discussed here. Like Zoom and Vonage Advanced, it doesn’t integrate with external video conferencing tools.

There’s no customer service live chat support either, and helpdesk support is limited to Salesforce. GoTo does cater to several different CRM software, however, so ultimately it depends on the software you need to be interlinked.

How Did We Compare Enterprise Phone Solution Providers?