(2025 market guide and comparison)
TL;DR: If you are an MSP or telco building a profitable voice practice, choose SIP trunking providers that simplify billing, compliance, and migrations. Viirtue ranks #1 for white label SIP trunking and wholesale SIP trunking because it combines a modern quote-to-cash platform with automated usage rating, telecom tax automation, built-in STIR/SHAKEN, and powerful self-service carrier features.
Looking for the best wholesale SIP trunk providers to power your MSP or telecom practice in 2025? SIP trunking remains one of the most profitable ways to deliver voice services, but the right partner makes all the difference. From automated usage rating and telecom tax compliance to STIR/SHAKEN call authentication and POTS replacement, today’s top providers must offer more than just dial tone.
In this guide, we compare the leading wholesale and white label SIP trunking providers and explain why Viirtue ranks #1 for MSPs and telcos that want full brand control, self-service carrier tools, and a modern quote-to-cash platform.
1) What is wholesale and white label SIP trunking?
Wholesale SIP trunking lets carriers, telcos, and MSPs buy voice capacity and phone numbers at scale, then deliver trunks to PBXs, SBCs, and UC platforms with their own pricing and routing logic.
White label SIP trunking adds full branding control so you sell under your own name while the underlying network and compliance are operated by your provider.
2) Why does Wholesale SIP Trunking matter in 2025?
STIR/SHAKEN is table stakes. Caller ID authentication helps prevent spoofing and is now a core requirement.
You need a provider that handles signing for you and keeps up with rule changes.
Copper retirement is accelerating. As carriers decommission copper, analog lines for alarms, elevators, fax, postage machines, and other devices need a plan.
This creates a strong POTS replacement opportunity for MSPs and telcos already delivering trunks.
3) How we evaluated SIP trunking providers:
White label readiness and channel posture
Usage-based rating and automated billing, including telecom tax handling
STIR/SHAKEN implementation and compliance support
Porting tools, E911 options, and day-to-day operations
POTS replacement, alignment, and handoff flexibility
APIs, automation, and documentation quality
Network reliability and geographic reach
4) Rankings: Top wholesale SIP trunk providers for MSPs and telcos
1. Overall winner – Viirtue:
Best for MSPs that want white label sip trunking with turnkey quote to cash, automated usage rating, tax automation, self-service carrier tools, and STIR/SHAKEN handled for you.
- White label focus: Yes
- Usage rating automation: Yes
- Telecom tax automation: Yes
- STIR/SHAKEN handled: Yes
- POTS replacement fit: Strong
- Standout trait: All-in-one quote to cash with self-service carrier tools
2. Telnyx:
Programmable, API-centric approach with strong documentation and global reach.
- White label focus: Partial
- Usage rating automation: Via APIs
- Telecom tax automation: Third party
- STIR/SHAKEN handled: Yes
- POTS replacement fit: Strong
- Standout trait: Programmable global SIP
3. Bandwidth:
Enterprise-friendly footprint with broad numbering and BYOC (Bring Your Own Carrier) options.
- White label focus: Program
- Usage rating automation: Via APIs
- Telecom tax automation: Third party
- STIR/SHAKEN handled: Yes
- POTS replacement fit: Strong
- Standout trait: Tier 1 scale and BYOC
4. Commio (thinQ):
Multi-carrier routing focus and channel-friendly model.
- White label focus: Yes
- Usage rating automation: Via platform
- Telecom tax automation: Third party
- STIR/SHAKEN handled: Yes
- POTS replacement fit: Strong
- Standout trait: Multi-carrier routing
5. Sangoma Wholesale Carrier Services (VoIP Innovations):
Carrier services portfolio for resellers and compliance options.
- White label focus: Yes
- Usage rating automation: Via platform
- Telecom tax automation: Tools available
- STIR/SHAKEN handled: Yes
- POTS replacement fit: Strong
- Standout trait: Wholesale carrier stack
6. Flowroute:
Software-centric routing controls and an established developer audience.
- White label focus: Some
- Usage rating automation: Via APIs
- Telecom tax automation: Third party
- STIR/SHAKEN handled: Yes
- POTS replacement fit: Strong
- Standout trait: Software-centric controls
7. DIDWW:
International numbering depth and two-way SIP.
- White label focus: Some
- Usage rating automation: Via APIs
- Telecom tax automation: Third party
- STIR/SHAKEN handled: Yes
- POTS replacement fit: Strong
- Standout trait: International DID coverage
8. SignalWire:
A developer-forward platform for programmable voice and SIP.
- White label focus: Partial
- Usage rating automation: Via APIs
- Telecom tax automation: Third party
- STIR/SHAKEN handled: Yes
- POTS replacement fit: Strong
- Standout trait: Developer-first
9. Twilio Elastic SIP Trunking:
Mass scale and quick deployment, ideal for app-heavy use cases.
- White label focus: Partial
- Usage rating automation: Via APIs
- Telecom tax automation: Third party
- STIR/SHAKEN handled: Yes
- POTS replacement fit: Strong
- Standout trait: App ecosystem
10. Skyetel and SIPTRUNK:
Accessible programs for smaller MSPs that want a faster start.
- White label focus: Yes
- Usage rating automation: Varies
- Telecom tax automation: Options
- STIR/SHAKEN handled: Yes
- POTS replacement fit: Moderate
- Standout trait: Quick start for MSPs
5) POTS replacement playbook for MSPs and telcos
Why act now
Copper retirement is pulling forward timelines to modernize analog endpoints. This is a high-margin, services-rich project type for MSPs and telcos.
What to replace
Fire and life-safety panels, elevators, fax, security systems, blue light phones, ATMs, POS terminals, postage machines, utility meters, and other single-line devices.
How Viirtue resellers can deliver it
You have three flexible paths depending on device, budget, and the customer’s existing gear:
Replace the analog line with a Class 5 seat
Ideal for postage machines and similar single line devices that benefit from straightforward dial tone and optional features.
Turn up a Viirtue Class 5 seat, attach a small ATA if needed, and you are live.
Use Viirtue’s Class 4 services only, for maximum cost efficiency
When you simply need carrier grade trunking to present dial tone to analog devices at scale, use Viirtue’s Class 4 trunking without the Class 5 feature layer.
Map numbers, routing, and E911 in the portal and keep costs lean.
Handoff as PRI to legacy systems
For sites that must keep an older PBX or security panel interface, hand off dial tone as PRI from a gateway while sourcing trunks and numbers from Viirtue.
This lets you modernize the carrier side now while deferring a full PBX rip and replace.
Packaging tips
Offer a simple monthly price per converted line that includes trunks, device or gateway, LTE failover if required, monitoring, and support.
Bundle with number porting, E911, and compliance documentation.
Use Viirtue’s automation to rate usage, calculate taxes, and invoice under your brand.
6) Viirtue self-service carrier features
Give your team and your MSP partners real control without tickets or long waits.
Provisioning
Activate SIP trunks, channels, DIDs, and E911 in minutes from one portal.
Emergency routing
Set and test emergency failover routes at the trunk or number level so calls keep flowing during outages.
Self-service number ordering
Search and buy numbers by area code, rate center, or vanity patterns. Instantly assign to customers or reserve for projects.
Self-service LNP platform
Create branded LOAs and RespOrg requests, send for e-signature, track carrier updates, and schedule FOC dates.
Self-service CNAM
Update customer CNAM records in seconds from the portal.
These tools cut handling time, reduce back and forth with carrier ops, and help eliminate revenue leakage.
9) Wholesale SIP Trunking FAQs
What is white label SIP trunking and why should MSPs care?
You sell trunks under your own brand while the provider runs the network and compliance. It speeds time to market and preserves your margins.
How many SIP trunks or channels do I need?
Plan for peak concurrent calls, codec bandwidth, and failover. Add headroom for growth.
What is STIR/SHAKEN and do I need it?
Yes. It is caller ID authentication designed to stop spoofing. Your provider should sign calls for you and keep certificates current.
What is POTS replacement?
It is the migration of analog lines from copper to IP or cellular transport. Package gateways or ATAs with trunks and monitoring to replace lines serving alarms, elevators, fax, postage machines, and similar devices.
Does Viirtue handle usage rating and telecom taxes?
Yes. Viirtue’s platform automates usage-based rating, tax calculation, invoicing, and payments under your brand.
Does Viirtue handle STIR/SHAKEN?
Yes. Viirtue signs calls so you do not have to manage call authentication yourself.
Can I hand off as PRI to a legacy PBX?
Yes. Use a gateway to present PRI while sourcing trunks and numbers from Viirtue.
What is Class 4 vs Class 5, in plain terms for MSPs?
Class 4 is the carrier transit layer. Think high-capacity switching and routing of calls between networks. It focuses on trunking, routing policies, least cost routing, and interconnects. It does not include end-user feature sets like voicemail or auto attendants. Use Class 4 when you only need dial tone to a device or a legacy PBX, when you want the leanest cost, or when you plan to hand off as SIP or PRI from a gateway.
Class 5 is the subscriber feature layer. It provides dial tone plus end-user features like voicemail, hunt groups, auto attendants, CNAM updates, call forwarding, and E911 per location. Use Class 5 seats when a single-line device or user needs feature control or when you want to present a full PBX-like experience without a legacy system.
Rule of thumb: devices and simple single-line replacements can run on a Class 5 seat with an ATA. Legacy PBX sites or bulk dial tone at scale can run on Class 4 trunking, with optional PRI handoff from a gateway.
