ChatGPT
Claude
Perplexity
Gemini
Meet your local partner
At a glance
- Ooma Office Pro: $24.95/user/month, no contract; recording, 25-person video, 250 texts/month.
- RingEX Advanced: $25 annual / $35 monthly; automatic recording, CRM integrations, 100-person video.
- Zoom Phone US & CA Unlimited: $16 annual / $18 monthly; includes Workplace Basic (40-minute meetings).
- Checked September 27, 2026.
Compare three actual phone plans
Swipe or scroll sideways to compare all options.
| Feature | Ooma Office Pro | RingCentral RingEX Advanced | Zoom Phone US & CA Unlimited + Workplace Basic |
|---|---|---|---|
| Ten-user monthly equivalent | $249.50 | $250 at annual rate | $160 at annual rate |
| Published service reference | $24.95/user/month | $25/user/month annually; $35 monthly | $16/user/month annually; $18 monthly |
| Domestic calling | Unlimited under plan terms | Unlimited US/Canada under plan terms | Unlimited US/Canada under plan terms |
| Desktop and mobile calling | Included | Included | Included |
| Recording | Included | Automatic recording included | Included |
| CRM distinction | Salesforce integration requires Pro Plus | CRM integrations included at Advanced tier | Salesforce integration listed |
| Included meeting distinction | Up to 25 participants | Up to 100 participants | Workplace Basic: 100 participants, 40-minute meeting limit |
| Main upgrade trigger | Queues or Salesforce: evaluate Pro Plus | More analytics: evaluate Ultra | Longer meetings: Pro Plus bundle, $20.50 annual |
| Buyer fit | Small office with conventional phone needs | Business whose calls feed a CRM workflow | Calling-focused team already comfortable with Zoom |
| Main limitation / extra cost | Salesforce and queues can require Pro Plus; phones and fees extra | $25 rate requires annual billing; monthly term is $35 | Included Basic meetings stop at 40 minutes; longer meetings require another entitlement |
| Best fit (Sigma assessment) | You need desktop calling and recording, with meetings of 25 or fewer | You need automatic recording and the Advanced tier's CRM integrations | You prioritize the lowest listed calling price and can accept Basic meeting limits |
| Official sources | Ooma: Small business phone plans | RingCentral: RingEX plan prices and own-product features (August 2026) RingCentral: RingEX plans and pricing |
Zoom: Zoom Phone plans and pricing Zoom: Zoom Phone product features and package limits |
Sources: Ooma’s live matrix; RingCentral’s own published plan description; Zoom’s current phone pricing and product page. Taxes, hardware and optional services are outside these references. RingCentral’s quoted transaction terms should confirm the published rate.
The lowest rate is not the lowest complete solution
Zoom has the lowest annualized service reference in this table. For ten users its $1,920 annual base is $1,080 below RingEX Advanced at $3,000. The comparison changes if those Zoom users also need a paid meeting bundle or another capability not included in the phone offer.
Ooma Pro is only fifty cents a month below RingEX Advanced for ten users at the listed rates, but Ooma’s monthly reference and RingCentral’s annual rate are different commitments. That near-equal monthly figure should not hide a contract difference. Select the billing term before comparing the total.
If only two employees need advanced call features, establish whether the supplier permits the required license mix. Do not assume every platform lets a small account mix any editions freely. A quote should show the actual paid user count, common-area endpoints and extra numbers separately.
Which differences will employees notice?
A receptionist will notice whether calls can be transferred easily and how unanswered calls are handled. A salesperson will notice whether a call reaches the correct CRM record. A remote employee will notice whether the desktop application, headset and mobile fallback work together. These tasks matter more than the total number of features on a marketing page.
The table points to specific tests. Demonstrate Ooma Pro’s desktop calling and recording. Demonstrate RingEX Advanced’s actual CRM connector, including the fields and permissions your staff need. Demonstrate a Zoom Phone call and then a meeting; the Basic meeting limit is a separate constraint even though both appear in the same application.
Recording and texting deserve their own checks
“Recording included” does not answer retention, storage, access rights or automatic versus manual behavior. Specify which calls should be recorded and who can retrieve them. Confirm the applicable consent requirements with appropriate guidance for your business before enabling recording.
Business texting also has operational conditions. Ooma Pro lists up to 250 messages a month. Other providers have their own allowances and registration requirements. If appointment reminders or customer conversations depend on texting, obtain the supported workflow and complete message charges. Unlimited calling does not establish unlimited SMS.
The fine print outside the user price
Desk phones, headsets, extra numbers, international destinations, toll-free usage and implementation can add cost. A contact-center requirement is also different from an ordinary phone extension. A business that needs sophisticated queues, supervisor tools or detailed agent reporting should compare the relevant edition instead of expecting the cheapest phone tier to provide everything.
For an existing office, check supported phones before deciding they can be reused. Confirm network ports, power delivery and any provisioning work. A low subscription price is less useful if a complete hardware replacement was omitted from the proposal.
Choose from a working demonstration
Use one real incoming-call scenario: a customer calls the main number, hears the greeting, reaches a person, is transferred, and leaves voicemail if no one answers. Then test after-hours behavior and the mobile application. Repeat it on the shortlisted plans using the editions in the table.
Choose Ooma Pro if its office features satisfy that test without a more advanced tier. Choose RingEX Advanced if its integrations and monitoring solve a defined requirement. Choose Zoom Phone if its calling package and meeting limitations fit the team. A clear, demonstrated difference is a better reason to buy than a generic “best overall” badge.
What 25 users cost per year
| Plan | Rate used | 25 users, per year |
|---|---|---|
| Zoom Phone US & CA Unlimited | $16 annual | $4,800 |
| Zoom Phone Pro Plus bundle | $20.50 annual | $6,150 |
| Ooma Office Pro | $24.95 monthly, no contract | $7,485 |
| RingEX Advanced | $25 annual | $7,500 |
| Ooma Office Pro Plus | $29.95 monthly | $8,985 |
Sigma calculations from published rates; before phones, taxes, fees and optional services.
Questions to ask before you buy
- Which features must be in the base tier: recording, CRM integration, queues or meetings?
- Is the price for annual or monthly billing, and what is the contract term?
- Which desk phones or headsets can we reuse?
- What does texting cost, and what registration is required?
- How are numbers ported, and what is the fallback if a port is delayed?
What Hawaiʻi businesses should check
All three are cloud services, so call quality in Hawaiʻi depends on your internet connection and office network more than on the brand. Test from your own office and from staff mobile phones before porting your main number.
Frequently asked questions
Do all three replace internet service?
No. They require a suitable connection and supported endpoints.
Can Sigma compare the complete installation?
Yes. Sigma compares the plan, user count, phones, number porting and transition work in one proposal so the totals are like for like.
Which is cheapest: Ooma, RingCentral or Zoom Phone?
Zoom Phone has the lowest published rate at $16 per user per month billed annually. Its included meetings stop at 40 minutes, so add a meeting license if you need longer calls.
Sources and pricing notes
Prices and specifications checked September 27, 2026 against the providers’ published sources below. Prices are US list or published rates before taxes, fees and equipment unless stated; offers change, so confirm the current terms before you buy.
- Ooma. Small business phone plans
- RingCentral. RingEX plans and pricing
- RingCentral. RingEX plan prices and own-product features (August 2026)
- Zoom. Zoom Phone plans and pricing
- Zoom. Zoom Phone product features and package limits
How Sigma is paid. Sigma is a Hawaiʻi technology advisor. Provider or reseller partners compensate Sigma; product and service prices may include a margin. No procurement fee applies. Standalone consulting is quoted separately.