Answer WhatsApp callson your phone system
Blue Chip SIP for WhatsApp bridges voice calls from the WhatsApp and WhatsApp Business apps on a mobile device into your IP PBX — SIP trunk style. Keep the number customers already know, run inbound through desk phones, softphones, and queues, and place outbound calls WhatsApp-first with automatic landline fallback when needed.
Simultaneous calls on the same WhatsApp number
Regular WhatsApp and WhatsApp Business mobile apps typically handle one call at a time on a number. Blue Chip's SIP bridge lets concurrent calls run on that same WhatsApp number — so more than one customer can reach you at once, with capacity in blocks of 2.
One handset is not a call centre
Customers already call businesses on WhatsApp. The problem is treating that number like a single mobile phone instead of a shared business line.
What breaks today
- Only one person can answer while the handset is busy or offline
- Missed WhatsApp calls with no proper queue or follow-up path
- Sales, support, and reception fighting over the same device
- No clean after-hours greeting or business-hours routing
- Growth limited by how many people can stand near one phone
What changes with a PBX bridge
- WhatsApp voice calls land on your SIP-based IP PBX
- Multiple agents can share one customer-facing WhatsApp number
- Simultaneous calls on the same WhatsApp number — not one-at-a-time like a regular WhatsApp handset
- Desk phones and softphones become first-class answer points
- Outbound calls can try WhatsApp first, then fall back to the regular landline route
- The familiar WhatsApp app stays how customers reach you
Why PBX integration matters
Once WhatsApp calling is presented as a SIP trunk, you can apply the same business voice controls you already trust for ordinary phone calls.
Desk phones & softphones
Ring WhatsApp calls to extensions on desk sets and softphones so the right person can answer without holding the mobile handset.
Shared number, many agents
Keep one WhatsApp number customers already save, while several team members handle inbound volume together.
Queues & overflow
Send busy periods into call queues so callers wait in line instead of bouncing off a single busy mobile.
AI receptionist
Route WhatsApp voice calls to an AI receptionist — or send them to a ring group, call queue, or a direct extension — without a DTMF IVR menu.
Transfer & presence
Blind or attended transfer between agents, with presence so calls go to people who are actually available.
Recording & reporting
Apply call recording, CDR, and reporting policies already configured on your PBX for quality and compliance needs.
Business hours
Open/closed schedules, after-hours announcements, and night service — without leaving a mobile on a desk overnight.
Simultaneous calls on one number
Unlike typical WhatsApp / WhatsApp Business mobile apps that handle one call at a time on a number, the SIP bridge supports concurrent calls on the same WhatsApp number — sized in blocks of 2 simultaneous calls per number.
Outbound WhatsApp auto-sensing
Place outbound calls from your PBX with WhatsApp first. Built-in auto-sensing checks whether the destination is on WhatsApp; if it is not, the call is rejected, or the person is busy, the gateway signals your PBX to use the secondary landline route on your outbound rules.
Works with SIP PBXs
Designed for SIP-based systems such as 3CX, Asterisk/FreePBX, PortSIP, and similar IP PBX platforms.
How the bridge works
A practical setup path for businesses that already use WhatsApp or WhatsApp Business on a mobile device and already run an IP PBX.
Provision the SIP for WhatsApp service
Blue Chip Technologies Ltd. sets up the SIP trunk path sized for the WhatsApp numbers and simultaneous calls your team needs.
Link the WhatsApp / WhatsApp Business app
Connect the mobile app customers already use — typically with a QR code link — so voice calls can be bridged without asking customers to change habits.
Connect to your IP PBX
Present WhatsApp calling to your PBX as a SIP trunk so you can route to a ring group or call queue, a direct extension, or an AI receptionist.
Configure outbound: WhatsApp first, landline second
Point PBX outbound rules at the SIP for WhatsApp trunk first. Auto-sensing detects whether the number is on WhatsApp and places the call there when it is. If the number is not on WhatsApp, the call is rejected, or the person is busy, the gateway tells your PBX to continue on the secondary landline route.
Route the way your business works
Send inbound calls to a ring group or call queue, a direct extension, or an AI receptionist — with business-hours rules and transfers between agents.
Outbound calling with WhatsApp auto-sensing
Inbound is only half the story. Your agents can dial from the PBX and prefer WhatsApp when the destination supports it — without changing how they place a call.
WhatsApp first
Configure the PBX so outbound calls try the SIP for WhatsApp path first. When someone is reachable on WhatsApp, the solution detects that and places the call there automatically.
- Same dialling habit for agents on desk phones and softphones
- Prefer WhatsApp voice when the destination is available on WhatsApp
- Keep your existing PBX outbound rule structure
Automatic landline fallback
Built-in auto-sensing checks whether a number is on WhatsApp. If it is not, or the person rejects the call or is busy, the gateway sends a signal back to your PBX so the call can continue on the secondary landline route configured in your outbound rules.
- No WhatsApp presence → fall through to the landline route
- Rejected or busy on WhatsApp → PBX can try the secondary path
- One outbound policy: WhatsApp first, PSTN second
Deployment options
Flexible hosting to match your requirements
Self-Hosted Solution
Connect your own device to our service and keep control of the WhatsApp account
- Scan a QR code to link WhatsApp to our gateway
- Use your existing WhatsApp or WhatsApp Business number
- Maintain full control of your WhatsApp account
- Real-time call routing to your PBX
- Ideal for businesses wanting direct control
Blue Chip Hosted Gateway
We host the WhatsApp number and manage the gateway on your behalf
- Blue Chip manages the gateway infrastructure
- We handle setup, monitoring, and day-to-day upkeep
- Sized for the numbers and simultaneous calls you need
- Local support within Trinidad & Tobago
- A good fit when you would rather not run the gateway yourself
Technical specifications
Standards-based SIP for reliable integration
Protocol Support
- SIP/SIP-TLS
- WebRTC
- ICE/STUN/TURN
- RTP/SRTP
Audio Codecs
- Opus (16kHz - HD)
- G.722 (16kHz)
- G.711 (8kHz)
- Automatic negotiation
Security
- TLS 1.2/1.3 encryption
- DTLS-SRTP for media
- Trusted SSL certificates
- Signalling and media over encrypted transport
PBX Compatibility
- 3CX
- Asterisk/FreePBX
- PortSIP
- Most SIP-based systems
Built for teams that have outgrown the WhatsApp handset
A strong fit when customers already call you on WhatsApp and you need real multi-agent handling behind that number.
A strong fit when you
Customers already call you on WhatsApp, and a single handset can no longer keep up.
- Already receive customer voice calls on WhatsApp or WhatsApp Business
- Run a SIP-based IP PBX and want WhatsApp calls inside it
- Need simultaneous calls on the same WhatsApp number — not one-at-a-time like a regular WhatsApp app
- Want routing to a ring group or call queue, a direct extension, or an AI receptionist (no DTMF IVR)
- Need transfer, recording, and office-hours control on that traffic
- Want outbound dialling that tries WhatsApp first, then falls back to landline
What you keep
Bridge WhatsApp calling into the phone system your team already knows.
- The WhatsApp number customers already know
- The familiar WhatsApp / WhatsApp Business calling experience for callers
- Your existing PBX investment and agent workflows
- Room to scale simultaneous calls as volume grows (blocks of 2 per number)
- Local Blue Chip support in Trinidad & Tobago
Request a SIP for WhatsApp quote
Tell us how many WhatsApp numbers and simultaneous calls you need on the trunk. A Blue Chip specialist will follow up with a practical quote.
You can associate any number of WhatsApp numbers with the trunk (1, 2, 3...). Simultaneous calls are sized in blocks of 2, with at least 2 concurrent calls per WhatsApp number — for example, 3 numbers means a minimum of 6 concurrent calls, while a single number can request 6, 10, or more, as long as the total is a multiple of 2.