Office Phone Systems: 7 Systems Compared With Real Prices

An office phone system gives every person an extension, sends callers to the right desk through a phone menu, and works on desk phones, computers and cell phones. Almost every system sold to small offices today runs in the cloud and is priced per user, per month. Below are seven of them with prices from each company's own site, what each one costs for a 5- and 10-person office, and how to choose.

Office phone systems compared

Prices from each company's own pricing page. Taxes and regulatory fees are extra on every system. Zoom Phone's month-to-month prices are on Zoom Phone pricing.

Every plan's price, side by side

What an office phone system costs for 5 and 10 people

Our math: per-user price times the number of people, at list price before taxes and fees. Grasshopper charges one price per account, so 5 and 10 people cost the same on its Small Business plan, which has unlimited extensions (Grasshopper). Google Voice adds Google Workspace Starter at $7 a user on Google's annual plan ($8.40 flexible). Vonage's lowest price needs a 1-year contract, and its Mobile plan does not support desk phones; with desk phones on Premium, five people cost $104.95 a month on the annual contract (Vonage).

The cheapest line in the chart is not always the cheapest office. Two plans near the bottom leave out something most offices want: Grasshopper sells no desk phones, and Google Voice Starter has no phone menu. If your office needs both a receptionist-style menu and handsets on desks, Zoom Phone is the lowest entry plan in this group that lists both on every plan: $16 a user billed annually or $18 billed monthly. Ooma Office, at $19.95, is the lowest with no contract at all.

The first plan with a phone menu

Because the phone menu is what turns a set of phone numbers into an office system, price the first plan that has one, not the cheapest plan on the page.

Annual vs monthly billing: what committing saves

Our math: the monthly difference for five people times 12. Paying a year ahead saves $600 on RingCentral Core and $360 on Vonage Mobile, but Vonage ties that saving to a contract with early termination fees. Ooma Office has one price, so there is nothing to save and nothing to lose. If your team size may change within a year, monthly billing or a no-contract system is the safer choice.

The seven systems, one by one

Types of office phone systems

"Office phone system" covers three setups. They differ in who runs the equipment and how you pay.

Every system in the comparison above is a cloud system. For how the switching box behind all of these works, see what is a PBX, and for the cloud version specifically, hosted PBX.

Features an office phone needs, by system

From each company's pricing and plan pages. "Not stated" means the company's pricing page does not say.

Office phones: desk, cordless or apps

Every system here includes mobile and desktop apps, so a desk phone is optional. When you do want handsets, check the provider's supported list first, because support varies more than price.

For a wireless business phone system, the simplest route is the mobile app every provider includes. If you need real handsets without cables, DECT systems pair cordless handsets with a base station, and Wi-Fi phones join your existing wireless network. Models, line counts and prices are on VoIP phones; for systems built around many lines on one desk, see multi-line phone systems.

Toll-free numbers and texting for an office

An 800 number is included on some plans and missing from others. Ooma Office includes one free toll-free number with 500 inbound minutes a month; RingCentral includes toll-free minutes by plan (100 minutes on Core, 1,000 on Advanced, 10,000 on Ultra); Nextiva adds a toll-free number on its higher plans (Engage: toll-free number + 2,000 minutes; Scale: + 10,000); Zoom sells extra local or toll-free numbers at $5 a month each (Zoom); Grasshopper offers local, toll-free or vanity numbers (Grasshopper); Google's Voice plan comparison lists local numbers only. For more, see toll-free business numbers.

Grasshopper and Vonage both require registration before business texting. Grasshopper lists the cost openly: $19.50 once and $1.50 a month. Vonage says Campaign Registry fees apply to the mandatory registration for SMS. Ooma includes texting only from Pro, with up to 250 messages a month.

Remote and hybrid offices

Every system here runs on cell phones and computers through its apps, so staff can answer the office number from home. The differences are in meetings and chat: Vonage Premium adds video meetings for up to 200 people and team messaging; Ooma adds video for up to 25 on Pro and up to 100 plus team chat on Pro Plus; Google Voice works inside Gmail and alongside Meet. Hot desking, where staff sign in to a shared desk phone, is listed on Ooma Pro Plus.

How many lines does an office need?

With a cloud system you do not buy "lines" the way you did with copper. You pay for users (sometimes called extensions or lines), and each user can take calls at the same time as the others. The practical count is the number of people who answer calls, plus any shared phones such as a lobby or a break room. Most systems price each of those as a user.

Grasshopper is the exception: it prices the whole account and limits extensions instead. True Solo has 1 extension, Solo Plus has 3, and Small Business has unlimited extensions, with extra numbers at $9 a month each (Grasshopper). Vonage calls its unit a line on annual contracts and an extension on monthly ones; either way it is one unit per person.

Setting up an office phone system

Keeping your number is protected by federal rules. The FCC says simple ports must be processed in one business day and your old company cannot refuse to port your number, even if you owe money (FCC). It also advises not to cancel your existing service before starting service with the new company (FCC). Ooma says porting regular US and Canada numbers is free, and that its phones arrive set up so installation takes about 15 minutes (Ooma).

Moving from a landline or an old phone system

Many offices are switching because their copper lines are going away; the FCC describes the tech transition as moving network infrastructure from copper wire to optical fiber (FCC). Three things keep the move smooth. First, start the port with the new provider and keep the old service running until the number moves. Second, check the old contract: the FCC notes it may contain early termination fees or outstanding balances you must still pay (FCC). Third, if you are replacing an on-site system that makes staff dial 9 for an outside line, make sure the new setup lets anyone dial 911 directly. More on the trade-offs: VoIP vs landline and business landline service.

911 rules every office phone system must meet

Two federal requirements apply directly to office phone systems with several lines.

• Direct dialing (Kari's Law). Anyone must be able to call 911 from any station without first dialing a 9 or any other prefix (47 CFR 9.16).
• Notification. When someone dials 911, the system must alert a central location, on site or off, where someone is likely to see or hear it (FCC). Installers, managers and operators must make sure direct dialing works (FCC).
• Your address on file. VoIP providers must provide 911 as a standard feature, may not let you opt out, and must collect your physical location before service starts (FCC).

Cloud phones need power and internet. Phone companies whose service is not powered by the line must tell new customers about backup power and offer a battery with at least 24 hours of standby (FCC).

Costs beyond the plan price

Office phone systems by office size

Which office phone system to choose

Five mistakes that raise the bill

1. Pricing the plan without the menu. On Google Voice the menu costs $10 more per user than Starter; check which plan carries it on every system.
2. Signing for a year before your headcount settles. Vonage's early termination fees can reach the full contract price.
3. Forgetting texting registration. It is a separate fee on Grasshopper and Vonage, and Ooma's entry plan has no texting.
4. Buying phones the provider does not support. Google Voice works with HP Poly phones; Zoom asks for Zoom Certified phones; Grasshopper supports none.
5. Leaving 911 addresses blank. Providers must collect each location before service starts, and multi-line systems must allow direct 911 dialing.

Questions to ask before you sign

1. Is the phone menu on the plan I am pricing, or only on a higher one?
2. Which desk phone models do you support, and can I bring the ones I own?
3. Is the low price an annual contract, and what does it cost to leave early?
4. What texting registration fees will I pay, and how many texts are included?
5. Is a toll-free number included, and how many minutes come with it?
6. How does 911 notification work on your system, and where do I update each user's address?
7. What happens to calls when our internet or power goes down?

Related: cloud phone systems and the Zoom Phone review.