Are you using Sipwise?

Meet Kolmisoft, the Sipwise alternative for VoIP providers that want a simpler, more affordable Class 4/5 Softswitch with built-in billing and routing.

 

About these comparison notes

The themes below come from Kolmisoft CRM sales and support notes that mention Sipwise. Individual notes run from 2013 through 2026. We reviewed them for this page in October 2026.

A note from 2017 describes that operator’s experience in 2017. It is not a claim about Sipwise’s product in 2026. Where a year appears next to a point, that is the year of the CRM note.

We paraphrase operator themes here. We do not publish customer names on this page.

 

Company focus

Kolmisoft Sipwise
Kolmisoft focuses on a narrow niche: the development of MOR and M4 softswitches with in-built billing and routing functionality.

This focus helps us cut distractions, develop stable softswitches, and maintain technical support.

 Sipwise focuses on the design, development and integration of carrier-grade, next-generation VoIP platforms.

Sipwise offers Class 5 and Class 4 softswitch solutions with Cloud PBX, WebRTC and mobile app modules.

 

Pricing

Kolmisoft Sipwise
Kolmisoft softswitches are designed for small and medium-sized VoIP providers that need a robust Class 4/5 Softswitch, with billing and routing at a fair price. In our CRM notes (2018–2023), operators who compared commercial Sipwise often described budgets in the tens of thousands of euros (examples cited around €30,000+, and in one 2020 note a commercial license figure around €60,000). That matches how we position Sipwise for providers who can allocate a higher softswitch budget. Exact Sipwise list prices change by edition and modules—confirm with Sipwise.

 

Billing, resellers and subscriptions

Operators who already run Sipwise often come to Kolmisoft when billing and reseller workflows matter as much as the switch.

  • CRM note, July 2024. An operator using Sipwise as the core VoIP system said MOR’s services and subscriptions model looked stronger for reseller-oriented billing, and asked about using MOR only to bill and rebill calls that originated on Sipwise. Kolmisoft’s follow-up was that MOR was not a fit for that billing-only design. This is a workflow mismatch, not proof of a MOR–Sipwise product integration.
  • CRM notes, April–May 2017. An Austrian VoIP provider with about 70 customers on Sipwise wrote that accounting and reseller management were missing, and in a separate German message that a satisfactory billing module and monitoring were lacking. They also said Kolmisoft’s proposed monthly price was too high for a startup. Treat this as 2017 feedback for that deployment, not a 2026 product spec.

What to test with us: reseller hierarchy, services/subscriptions, prepaid, and invoice flows on a Pilot—not a slide claim that “Sipwise has no billing.”

 

Free edition vs commercial cost

Several notes describe teams on a free / open-source Sipwise edition who later hit billing or budget walls.

  • CRM notes, September 2020. A prospect on the free edition wrote that they had never got billing working properly and could not make the commercial edition make sense on price (the same thread mentions on the order of 100–200 seats and under 15 concurrent calls, and a wish to bring more infrastructure in-house). This records that prospect’s configuration and budget experience—not a lab proof that Sipwise billing is defective.
  • CRM note, December 2018. A cloud/ISP prospect who tested Sipwise called pricing “very expansive,” citing many modules and customization costs.
  • CRM notes, January 2022 and January 2023. A prospect with roughly 5,000 users / 200 concurrent calls had looked at Sipwise but wanted a lower-priced path; an internal 2023 meeting note again framed Sipwise as expensive and Kolmisoft as more affordable. That prospect later ran a Kolmisoft pilot and postponed migration—so this is comparison context, not a finished win story.

What to test with us: whether MOR/M4 pricing and in-product billing cover your seat and concurrent-call plan without a module maze.

 

Administration and day-to-day operations

  • CRM note, October 2022. A salesperson summarized a retail telecom prospect: Sipwise felt complicated; MOR looked easier for growth. That is a sales summary, not a verbatim customer quote. The same prospect also needed specific billing rounding and AMR-WB capability from Kolmisoft.
  • CRM note, October 2025. A team on open-source Sipwise looked for an alternative after the company that administered their SBC would no longer support it. Billing sat elsewhere (another PBX), not on Sipwise.

What to test with us: time-to-configure common reseller and routing tasks with your staff, not ours.

 

When a platform change forces a second look

  • CRM note, April 2026. A long-time Sipwise user moved to a new version after a datacenter issue, hit problems during that transition, and asked about Kolmisoft (including API). The note does not name the issues or their severity. Do not read this as “Sipwise is unstable”—read it as a forced upgrade trigger to evaluate options.

 

Balance: why some operators choose or keep Sipwise

A fair comparison includes the other direction.

  • CRM note, March 2023. A long-term MOR user moved their growing residential core to Sipwise C5 Carrier, citing API usage and high availability as reasons to concentrate on one platform. In the same note they praised MOR’s LCR, provider management, call statistics, and support.
  • CRM note, November 2013. After choosing Sipwise (free availability was a factor earlier), one operator said setup was tedious but the platform performed well at about 100 concurrent calls. A March 2014 follow-up then reported trouble assigning a specific provider to an individual customer in their Sipwise setup. That routing point is historical and unverified against today’s Sipwise editions.

Sipwise remains a serious Class 5 / carrier-grade option. Kolmisoft is usually the better fit when integrated billing, reseller workflows, and budget dominate the decision—and when you want a vendor focused on MOR and M4 rather than a broad module catalog.

 

Wondering where to start?

Here are some useful resources: