Cisco SPA 504G IP phone – Review

The Cisco SPA 504G IP phone is suitable to be used at homes, small businesses and large organizations that require quality branded IP phones from a leading vendor. This phone in particular, is very popular with enterprise organizations and corporate companies who provide IP phones to many of their employees. But home users can also buy this phone and use it with VOIP/SIP service providers, if they are looking for a nice enterprise grade phone that can last long, and has many features. The Cisco SPA 504G IP phone is a mid-level 4-line IP phone at a competitive price.

Video description of the Cisco SPA 504G IP Phone:

You might wonder why four lines are required in an IP phone? If you are a small business (for example), you can register one line with the on-premise/hosted PBX and register the remaining three lines with VOIP/SIP providers and use any of them while making a call (based on the cost/destination, etc). The Cisco SPA 504G IP phone supports HD voice and speaker phone (with on-hook dialing).

There are enough keys (soft keys and hard keys) that enable you to activate many features with the touch of a single button. LED indicators might be useful to identify the status of the call/phone status. There is a message waiting indicator that flashes when a voice mail is waiting for you and there is a 2.5mm headset port to connect to standard headsets, in call centers. There is a phone directory that stores up to hundred phone numbers and when you type a number, it even auto-suggests the possible numbers.  Most of the important telephony features are available in this phone.

Configuration is simple, with its web-based configuration utility and it supports POE (Power Over Ethernet), which enables data and electrical power to be sent over a single (ethernet) cable. Generally, one requires a POE switch or a POE adapter/injector to use this feature, but it simplifies the cabling a lot.

Applications: The Cisco SPA 504G IP/SIP phone can be used at homes, small businesses and large organizations for making phone calls over the IP (Computer) Network. It can be registered with a VOIP/SIP service provider (ITSP) to make/receive cheap overseas calls over the Internet from home or it can be registered as an end-point with on-premise IP PBX/hosted IP PBX to make/receive voice calls for small business/large companies.

Important features of the Cisco SPA 504G IP phone:

  • Monochrome LCD back-lit display (128 x 64 pixels)
  • Four independent lines
  • HD voice with full-duplex speaker phone
  • LED indicators for important phone functions
  • Four soft keys that can be digitally controlled
  • Four back-lit buttons
  • 2 x RJ-45 Ethernet ports (10/100 Mbps) for network connectivity
  • 4-way navigation key for menu navigation
  • Message waiting indicator
  • Separate Buttons for mute, headset, speaker phone, volume, hold, menu settings and voice mail access
  • 2.5 mm headset port
  • 1 – year hardware warranty, 90 day software warranty


  • Support for encrypted voice calls
  • Number auto-completion/Do-Not-Disturb
  • Comfort noise generation (to enable callers to identify that the call is connected, during prolonged silence)
  • Easy to use web-configuration interface
  • Download ring-tones, set different ring-tones for certain users, etc
  • SIP support enables it to work with any PBX/ITSP that supports SIP (open standard voice protocol)
  • Even if the phone is moved to some other data port in the network, it still remembers its profile
  • Two switch ports (present in the IP phone) enable one to connect the cable from the LAN to the phone and the cable from the computer, also to the phone. That way, additional switch ports in the LAN switches are not required for connecting the IP phones
  • High-Definition voice support for quality conversations


  • The back-lit LCD display could have been bigger
  • The phone doesn’t come with a power adapter. Unless you intend to use it with a POE switch/POE adapter/injector, you need to buy a power adapter separately at additional cost. You either buy this power adapter or buy the POE adapter/injector. There is no need to buy both
  • If you need to use the phone as an attendant console with BLF (Busy Lamp Field) indication for the receptionist, you can buy up to two additional SPA500 expansion modules, but they are quite expensive
  • The network ports support only 10/100 Mbps and do not support 1 GE (Gigabit Ethernet), which is the latest standard. Since computers are mostly connected through these phones, a high speed interface could have been useful

Further Information: Head to Cisco’s official page for SPA 504G IP phone, to get detailed specifications, data sheets, user-guides, trouble shooting information, etc.

Where to buy: If you live in the United States, you can buy the Cisco SPA 504G IP phone and accessories online from Amazon.

What other models to consider: You can look at these two entry-level IP phone models from Cisco, if you are looking for an even more cost effective option.

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