Desk phones
Ring a physical SIP handset directly on one of your numbers — even when SmileLine is unreachable — and understand exactly what that number gives up in return.
A desk phone line moves one of your numbers off SmileLine's call handling and onto a physical SIP handset. Calls go straight from the carrier to the phone on your desk, with SmileLine completely out of the path — so the phone keeps ringing even if SmileLine, or your internet-connected computers, are down.
That independence has a hard trade: SmileLine can no longer see the number's calls at all.
| On a desk phone line | On SmileLine |
|---|---|
| Rings your handset directly, always | Rings your team's devices via SmileLine |
| Works during a SmileLine outage | Depends on SmileLine being reachable |
| No ring groups, menus or opening hours | Full call routing |
| No voicemail, recording or AI receptionist | All included |
| Calls do not appear in call history | Every call on the timeline |
| No screen pop or patient matching | Both built in |
Moving a number to a desk phone is the practice owner's decision and takes effect for every caller. Most practices are better served keeping numbers on SmileLine and adding a backup number — the caller is then forwarded only when SmileLine can't take the call.
Turn a number into a desk phone line
You need the owner role, and the number can't be your outbound caller ID (pick a different caller ID first on Settings → Phone numbers).
Open Settings → Call routing and find the number's card.
Click Move to a desk phone… and confirm. The card switches to the desk-phone panel and shows Setting up for a minute or so.
When the panel shows the line is live, click Reveal SIP credentials. You'll see the three values every handset needs: server, username and password. Each reveal is recorded in the activity log.
Enter those values on your handset — pick your brand below for step-by-step instructions.
The settings every phone needs
Whatever the brand, the registration values are the same:
| Setting | Value |
|---|---|
| SIP server / registrar | sip.telnyx.com |
| Username / auth ID | from Reveal SIP credentials |
| Password | from Reveal SIP credentials |
| Port | 5061 with TLS (preferred) or 5060 with UDP/TCP |
| Registration expiry | 180 seconds |
| Codecs | G.711 A-law, G.711 µ-law, G.722 |
| STUN / ICE | off |
You can register more than one handset with the same credentials — they all ring together. The line carries up to two concurrent calls.
Receiving and making calls
The line starts inbound-only: the handset receives calls immediately, but can't dial out. UK and US law require emergency numbers (999/112/911) to work from any line that can place calls, so outbound activates only after you register the handset's physical address — click Register emergency address… on the number's card. Once the carrier confirms it, the panel shows Two-way and the handset can dial out (domestic numbers only).
If the practice moves, register the new address before relying on the handset for emergency calls — responders are dispatched to the registered address.
If the handset goes offline
Set a Backup number on the same card. If your handsets are unplugged or lose registration, the carrier forwards callers there instead — the same safety net SmileLine-handled numbers get.
Set up your phone
Yealink
T3x, T4x and T5x series IP phones.
Grandstream
GRP26xx series IP phones.
Poly
VVX x50 and Edge E series.
Fanvil
X-series IP phones.
Cisco
68xx and 88xx multiplatform phones.
Cordless (DECT)
Yealink W-series DECT base stations.
Analogue adapter
Keep an existing analogue phone with a Grandstream HT8xx.
Moving back to SmileLine
Click Move back to SmileLine on the number's card. The handset stops ringing, the line's credentials stop working, and SmileLine answers the number again — its routing starts unconfigured, like a newly bought number, so set it up on the same page.