Choosing an IP phone for an office starts with how each person will use it. Most staff need a basic four-account SIP phone; reception needs BLF keys and a larger display; a manager may want a wireless headset or video. Then come the network questions: PoE power and a Gigabit PC port.
This guide covers the handset, not the PBX, comparing the Fanvil, Grandstream and Cisco models AZEIDK offers under Network and Communication Systems, using official datasheet figures.
Key takeaways
- The number of SIP accounts on a phone is not the number of calls or PBX extensions. Most users need one account.
- Entry phones such as the Fanvil X303 have 10/100 ports, so a PC daisy-chained behind them is capped at 100 Mbps.
- In the X303 range only the X303P is PoE powered. The standard X303 needs a power adapter.
- The Cisco Desk Phone 9800 Series is multiplatform, and its datasheet gives 16 SIP lines on open SIP platforms.
- A DECT system such as the Fanvil W620P serves staff who move around the building: up to 10 handsets and 10 simultaneous calls per base.
In this article
- What is an IP phone and how is it different from a standard phone?
- How many SIP lines does an IP phone need?
- IP phone comparison: Fanvil, Grandstream and Cisco by the numbers
- Does an IP phone need a PoE switch?
- Gigabit ports on the phone: when do you need them?
- Headsets and Bluetooth
- When should you choose a DECT cordless phone instead of a desk phone?
- Meeting rooms and video calls
- Does a Cisco phone work with a Yeastar or Grandstream PBX?
- Common mistakes when buying office IP phones
- Frequently asked questions
- Summary
What is an IP phone and how is it different from a standard phone?
An IP phone (network phone) is a desk set that connects to the data network over an Ethernet cable rather than a copper extension line from the PBX. It registers with the PBX using a SIP account (username and password). SIP is the signalling protocol defined in RFC 3261, published by the IETF in 2002, and it sets up, modifies and ends call sessions.
So a Fanvil or Grandstream phone normally works with any SIP-capable IP PBX. What differs is integration depth (auto provisioning, directory, BLF), so check the PBX vendor’s compatibility list before ordering. Choosing the PBX and sizing extensions is covered in our IP PBX for business guide.
How many SIP lines does an IP phone need?
“12 lines” on a datasheet means the phone can register up to 12 SIP accounts at once, for example a personal and a department extension. It does not mean 12 operator lines.
- Typical staff: one account is enough, so a four-account phone such as the Fanvil X303 or Cisco 9841 covers the need.
- Reception and secretaries: what matters is the number of BLF keys (keys that show colleagues’ extension status and transfer with one press), not the account count.
- Managers and call centre supervisors: several accounts and many keys, such as the Fanvil X6U with 20 SIP lines or the Grandstream GRP2614 with 12 SIP accounts.
BLF keys and DSS screens
Some models label keys on a side screen. The Fanvil X4U has a 2.4-inch second screen with six DSS keys that page up to 30 across 5 pages. The X6U has two side screens with 12 keys that page up to 60. The Grandstream GRP2614 has a 2.4-inch second screen that shows digital BLF keys.
IP phone comparison: Fanvil, Grandstream and Cisco by the numbers
Figures come from official datasheets. “Not stated” means the figure is not published.
| Model | SIP accounts | Display | Network ports | PoE | Wireless | Headset |
|---|---|---|---|---|---|---|
| Fanvil X303 / X303P | 4 | 2.4-inch colour | Dual 10/100 | X303P only | Not stated | RJ9 port |
| Fanvil X4U | 12 | 2.8-inch colour + 2.4-inch DSS screen | Dual Gigabit | Yes | Wi-Fi and Bluetooth via USB dongles | RJ9 with EHS |
| Fanvil X6U | 20 | 4.3-inch colour + two 2.4-inch screens | Dual Gigabit | Yes | Built-in Bluetooth 4.2, Wi-Fi via USB dongle | RJ9 with EHS |
| Grandstream GRP2614 | 12 (4 line keys) | 2.8-inch colour + 2.4-inch | Dual Gigabit | 802.3af | Wi-Fi 6 (hardware 5.0 and later) and Bluetooth | RJ9 with EHS for Plantronics |
| Grandstream GXV3470 (Android 14) | 16 | 7-inch touch + 2 MP camera | Dual Gigabit | 802.3af or 802.3at | Wi-Fi 6 and Bluetooth 5.0 | RJ9 with EHS, 3.5 mm and USB |
| Cisco 9841 / 9851 | 9841: 4 line keys; 9851: up to 16 on open SIP platforms | 3.5-inch greyscale / 3.7-inch colour | Dual Gigabit | Class 2 / Class 3 | Not stated | Not stated |
| Cisco 9861 / 9871 | 16 on open SIP platforms | 5-inch colour / 5-inch touch | Dual Gigabit | Class 3 | Wi-Fi and Bluetooth 5.2 (except no-radio variants) | Not stated |
Brand background is in IP PBX and IP phone brands in Saudi Arabia and further models, such as the Fanvil V67 video phone and the Grandstream GRP2670 touch phone, are listed on the Fanvil, Grandstream and Cisco brand pages.
Does an IP phone need a PoE switch?
Not strictly, but it is the better office option: PoE carries power and data on one cable, so no desk needs an adapter. Under IEEE 802.3af a switch port supplies up to 15.4 W, of which about 12.95 W reaches the device after cable losses. IEEE 802.3at raises the minimum port output to 30 W.
Most desk phones are fine on 802.3af. The Cisco 9841 is Class 2 and the rest of the 9800 Series is Class 3. The Grandstream GXV3470 runs on 802.3af as Class 3 and on 802.3at as Class 4. On the Cisco 9861 and 9871, one key expansion module (KEM) runs on PoE Class 3; up to three KEMs need Power Adapter 3.
How do you size switch power for a batch of phones?
Compare total phone consumption with the switch’s PoE budget, not just the port count. The Fanvil X6U datasheet, for example, gives a maximum PoE consumption of 6.88 W, so by our own estimate (not a manufacturer figure) 24 phones × 6.88 W ≈ 165 W at full load, before any margin or accessories. Some switches reserve power by device class rather than actual draw, so check how your switch allocates it. The method is explained step by step in our PoE switch power budget article, and the same logic applies to phones.
Gigabit ports on the phone: when do you need them?
Every phone in the table has a network port and a PC port, so the PC can sit behind the phone on a single wall outlet.
The catch is that the PC can only run as fast as the phone’s port. The Fanvil X303 and X303P have 10/100 Mbps ports, so a PC behind them stays at 100 Mbps even on a Gigabit switch. For heavy file users, choose a Gigabit phone (Fanvil X4U, Grandstream GRP2614, any Cisco 9800) or a separate data point.
Headsets and Bluetooth
For reception and sales staff a headset is a working tool. There are three connection types:
- RJ9 port: for a corded headset. Found on the X303, X4U, X6U, GRP2614 and GXV3470.
- EHS: lets the user answer and end calls from a wireless headset away from the desk. The X4U and X6U support it with a Poly APD-80 cable or a Fanvil EHS20 cable for Jabra; the GRP2614 and GXV3470 support it with Plantronics headsets.
- Bluetooth: built into the X6U, GRP2614, GXV3470 and Cisco 9861 and 9871, and available on the X4U through a BT20 USB dongle.
When should you choose a DECT cordless phone instead of a desk phone?
Staff who move around a warehouse, showroom or several floors need DECT: a networked base registers with the PBX and cordless handsets connect to it.
The Fanvil W620P is an example. Per its datasheet, one base supports up to 10 handsets, 10 simultaneous calls and 20 SIP accounts. Range is up to 50 m indoors and 300 m outdoors in ideal conditions. The base runs on PoE or a 5 V adapter, and handset talk time reaches 13 hours. Concrete and steel racking cut range, so survey coverage on site before fixing the number of bases. DECT frequency bands differ by region, so order the correct regional variant.
Meeting rooms and video calls
Not every meeting room needs a dedicated device. A desk phone can host a small audio conference: the Fanvil X4U and X6U support 6-way audio conferencing. The Grandstream GXV3470 video phone supports 10-way audio conferencing and 3-way video, which suits a manager’s office or a small meeting room.
For larger meetings, use a PBX conference room rather than one handset; large rooms need dedicated audio in the room design.
Does a Cisco phone work with a Yeastar or Grandstream PBX?
The Cisco Desk Phone 9800 Series datasheet describes the range as multiplatform and lists Webex Calling, Cisco Unified CM, BroadWorks and Asterisk among supported platforms. On open SIP platforms it gives 16 SIP lines, rising to 130 on Cisco Unified CM.
The 9800 Series suits companies on Webex or Unified CM, or standardising network and phones on one brand. With a Yeastar or Grandstream UCM PBX, Fanvil and Grandstream phones are usually easier to auto provision, so confirm compatibility before ordering.
Common mistakes when buying office IP phones
- Buying the standard X303 for a PoE office instead of the X303P.
- Daisy-chaining PCs behind a 10/100 phone in a department that handles large files.
- Sizing the switch by port count alone.
- Giving the receptionist, who transfers most calls, a phone with too few keys.
- Buying wireless headsets without checking the matching EHS cable.
- Installing DECT without a coverage survey.
Frequently asked questions
What is the difference between an IP phone and a PBX?
The PBX manages extensions and outside lines; the phone registers to it with a SIP account. Mixing brands works if both support SIP.
Does every employee need a 12-line phone?
No. Most users work on one SIP account. Larger phones suit reception and supervisors because of their keys and screens.
Can a network phone work without PoE?
Yes, with a power adapter. Some models do not include one in the box: the Fanvil X303 and X4U datasheets list the external supply as optional. Check the datasheet before ordering.
What is the best IP phone for reception?
Pick a phone with side DSS screens and plenty of BLF keys, such as the Fanvil X6U with its two side screens, and add a headset.
Can I use a Cisco phone with a non-Cisco PBX?
Usually, yes. The Cisco 9800 Series datasheet gives 16 lines on open SIP platforms and lists Asterisk among supported platforms. Confirm compatibility with your PBX model before buying.
How many cordless handsets does a Fanvil W620P base support?
Up to 10 handsets and 10 simultaneous calls per base, according to the official datasheet.
Summary
Group staff by how they use the phone, match accounts, keys and screen to each group, then check PoE, switch budget and port speed. The bill of quantities then reflects real use, not the priciest model in the catalogue.
Fitting out a new office or replacing old handsets? Send us your headcount, desk layout, PBX model and current switch, and we will propose suitable phone models with their datasheets. Talk to the AZEIDK team
