RingCentral is compatible with several popular desk phones across various brands. Here are some of the commonly supported desk phone models:

1. Polycom (now Poly)

• Polycom VVX Series: VVX 300, VVX 400, VVX 500, VVX 600, VVX 1500

• Polycom SoundPoint IP Series (older models)

2. Cisco

• Cisco 8800 Series: 8841, 8851, 8861

• Cisco 7900 Series: 7945, 7965 (with firmware updates)

• Cisco 7800 Series: 7811, 7821, 7841

3. Yealink

• Yealink T4 Series: T41S, T42S, T46S, T48S

• Yealink T5 Series: T54W, T56A, T58A

4. Grandstream

• Grandstream GXP Series: GXP1600, GXP2200, GXP2100, GXP3200

• Grandstream GRP Series: GRP2601, GRP2602, GRP2603

5. Snom

• Snom D7xx Series: D715, D725, D735

• Snom D3xx Series (with compatibility check)

6. Aastra

• Aastra Dialog 4000 Digital Series (older models)

7. Mitel

• Mitel 6900 Series

• Mitel 5300 Series

8. Unify (Siemens)

• OpenStage 40, 60, and 80

9. Avaya

• Avaya 9600 Series

RingCentral also supports certain softphones (desktop and mobile apps) and has native integration with these devices, allowing for VoIP functionality on a computer or mobile device.

Key Points:

• Firmware: Make sure the phone firmware is up-to-date for full compatibility.

• Provisioning: RingCentral provides automatic provisioning for many of these phones, simplifying the setup process.

• Features: The supported features (like voicemail, call forwarding, etc.) may vary by phone model.

If you're looking for a particular model or need assistance with setup, RingCentral’s website has a list of certified phones and guides to help with the installation process.