OnSIP Review 2026: Pricing, Pros, Cons, and Hidden Costs
The $18.95/user headline on OnSIP's pricing page looks great. Then you build out the system. A typical 10-user setup lands around $30-35/user once you add call recording, E911, queueing, and extra numbers. Support is excellent, the month-to-month flexibility is rare in this space, but the mobile app hasn't shipped a production update since October 2023. Let's break down what that actually means for your team.
30-Second Verdict
OnSIP fits small, desk-phone-primary teams that hate contracts. Budget $30-35/user realistically - not the $18.95 on the marketing page. The mobile app is stale (last updated October 2023), so skip this if your team lives on phones. Nextiva or RingCentral handle mobile and integrations better.
What Is OnSIP?
OnSIP is a cloud-based business VoIP platform covering voice, SMS/MMS, video calling, and conferencing. Over 150,000 businesses use it. The pitch: month-to-month contracts, no lock-in, pay for what you use. It's a phone system first - not trying to replace your CRM or become a full UC suite - and it does that job cleanly.
OnSIP Pricing Breakdown
Here's the thing: most teams don't stay at $18.95. There's a free plan for internal SIP-to-SIP calling up to 100 users, but it doesn't include external calling. That makes it useful only for internal comms between SIP devices, not as a real business phone system.
Plan Comparison
| Feature | Unlimited | Basic (Pay-as-You-Go) |
|---|---|---|
| Price | $18.95/user/mo | $49.95/account/mo |
| Min. users | 5 | None |
| Calling | Unlimited minutes | 3.2c/min |
| SMS/MMS | 250/account (1c overage) | 1c/outbound msg |
| Auto attendants | Unlimited | 3 |
| Ring groups | Unlimited | 3 |
| VoIP phones | Included | Not included |
| Music on hold | Enhanced (custom uploads) | Basic (default) |
The Unlimited plan is what most teams want. Basic only makes sense for very low call volume.
Key Add-Ons
From OnSIP's pricing page:
- Call recording: $4.95/user/mo
- E911: $1.80/user/mo
- Enhanced ACD queues: $14.95/user/mo
- Phone numbers: $2.00/mo each
- Porting: $15/DID + $2.00/mo/number
What a 10-User Team Actually Pays
Here's how the Unlimited plan math works for a 10-person team needing call recording, E911, extra numbers, and a single ACD queue for their support line:
- Base: 10 x $18.95 = $189.50
- Call recording: 10 x $4.95 = $49.50
- E911: 10 x $1.80 = $18.00
- ACD queue (2 agents): 2 x $14.95 = $29.90
- 5 extra numbers: 5 x $2.00 = $10.00
Monthly total: $296.90 - or $29.69/user. Add another queue or a few more numbers and you're at $31-35/user. Not outrageous, but a long way from $18.95.
OnSIP Pros: What Works Well
The Capterra rating sits at 4.7/5 across 78 reviews, and support scores a near-perfect 4.9/5. That's not inflated - it's the most consistent praise across every major review platform we checked.
99.99% uptime SLA backed by two data centers in NYC and LA with failover between them. Solid for this price tier. Month-to-month contracts with no annual lock-in make OnSIP worth considering for seasonal businesses or teams still figuring out headcount - a flexibility you rarely see from competitors at this level.
VoIP phones come included on the Unlimited plan, which is real cost savings when outfitting an office. SMS/MMS ships on both plans: 250 messages per account on Unlimited, with 1c overage.
OnSIP's included VoIP phones save you money - but reps still waste hours dialing wrong numbers. Prospeo's 125M+ verified mobile numbers hit a 30% pickup rate, 3x the industry average. Stop paying $30/user/month to ring dead lines.
Fix the data before you optimize the dialer.
OnSIP Cons: Where It Falls Short
We've tested the mobile app on both iOS and Android. The bugs are real. The production version, 1.13.218, dates to October 6, 2023 - over two years without a production update. There are 2.0 test builds in TestFlight and Android beta, but nothing's shipped. A December 2025 G2 review specifically calls out iPhone app bugs and a desktop app needing periodic restarts. For a mobile-first team, this is a dealbreaker.
If you're evaluating other providers because of mobile reliability, start with our breakdown of OnSIP alternatives before you commit.
Beyond the app situation:
- Add-on cost creep is the biggest frustration. Call recording, E911, and extra numbers should be table stakes, not line items.
- Integrations are thinner than platforms like RingCentral. HubSpot and Zendesk are the two most commonly cited, but if your stack is integration-heavy, expect workarounds.
- International calling covers landlines in 21 countries - decent, not great.
- Support runs business hours only for email and chat, while competitors like Nextiva offer 24/7 phone, chat, and email. OnSIP's G2 profile hasn't been active for over a year either, which is a soft signal they aren't investing heavily in competitive positioning.
What Real Users Say
G2 shows 4.1/5 from 28 reviews. Capterra lands at 4.7/5 from 78 reviews. Trustpilot sits at 4.5 from 928 reviews. The pattern is remarkably consistent: support gets praised universally, the mobile app gets criticized almost as often.
If you're comparing review patterns across tools, it helps to look at how other SaaS products hide costs too - see our framework for hidden costs in pricing pages.
One thing worth flagging: a 2021 Sonary review includes a user complaint that "SMS texting isn't a feature yet." That's outdated - OnSIP added SMS/MMS on both plans. Filter for post-2023 reviews when you're doing your own research.
Who Should Use OnSIP?
Use it if you're a 5-15 person team working primarily from desks, you hate contracts, and you value responsive support over feature breadth.
Skip it if your team is mobile-first, needs deep integrations, requires 24/7 support, or makes heavy international calls. And look - if your outbound team's connect rates are the real problem, no phone system swap will fix bad data. Fix the data layer first.
If you're rebuilding your outbound motion, pair better data with better sales prospecting techniques so reps spend time on real buyers.
Alternatives Worth Considering
Nextiva runs about $25-35/user/mo and is the obvious step up: 24/7 support, 99.999% uptime SLA, deeper analytics. For teams that've outgrown OnSIP's feature set, it's the natural move.
If you're also evaluating dialer-first stacks, compare against our list of Dialpad alternatives.
RingCentral starts around $20/user/mo on annual plans and is the integration king - Salesforce, Teams, Slack, and hundreds more. If your workflow depends on connecting tools, this is where you land.
If your team is building a cleaner system of record alongside VoIP, start with contact management software options that won’t fight your calling workflow.
GoTo Connect falls in the $25-35/user/mo range with a simpler admin experience. Good middle ground between OnSIP and RingCentral for teams that want more features without the complexity.
If your real bottleneck isn't the phone system but reaching the right prospects in the first place, that's a data problem. Prospeo operates at that layer - 98% email accuracy across 143M+ verified addresses and a 30% pickup rate on 125M+ verified mobile numbers. Free tier available, no contracts.
To tighten the top of funnel, consider adding data enrichment services so your CRM and dialer stop drifting out of sync.
Switching phone systems won't fix a 5% connect rate. Prospeo delivers 98% accurate emails and verified direct dials at $0.01/lead - less than a single OnSIP add-on. No contracts, just like OnSIP, but for the data layer that actually moves pipeline.
Reps book 35% more meetings when they reach real buyers.
FAQ
Does OnSIP have a free plan?
Yes - free internal SIP-to-SIP calling for up to 100 users with no external calling included. It's only practical for internal communication between SIP devices, not as a standalone business phone system.
Is $18.95/user the real cost?
No. Most teams pay $29-35/user after adding call recording ($4.95), E911 ($1.80), extra numbers ($2.00 each), and ACD queues ($14.95). A 10-user setup typically runs around $297/month total.
What if bad contact data is hurting connect rates more than the phone system?
That's exactly the scenario where swapping VoIP providers won't move the needle. Prospeo verifies emails and mobile numbers before your reps dial, so call blocks reach real people instead of dead lines. The free tier gives you 75 emails/month to test with no credit card required.