USA Telephone Wiring Color Code

The Backside of a Residential Telephone Jack
The Backside of a Residential Telephone Jack

Telephone Wiring Color Code for a Home

Dear Mr. Electrician.  I want to replace all of the old telephone jacks in my house, but am confused by the color code.  The new telephone jacks have red, green, yellow, and black terminals, but the telephone wiring in my walls have eight wires with different color stripes.  How do I connect the new telephone jacks?

Answer:  I have put together a telephone color code chart to help you understand how to connect the existing four pair telephone wiring in your walls to the new telephone jacks.  The four pair wire is capable of having four separate telephone lines at each jack location.  However if you only have one telephone line for your house, you should use the same color pair for each new phone jack that you install.  NOTE: Text links below go to applicable products on Amazon.

Front of the phone jack
“Tip” refers to that side of a two wire telephone circuit which is connected to the positive side of a battery at the telephone company’s central office.
“Ring” refers to that side of a two wire telephone circuit which is connected to the negative side of a battery at the telephone company central office.

Generally speaking the phone company connects the phone lines at their termination block in a certain order.  The blue pair is first, the orange pair is second, the green pair is third, and the brown pair is fourth.  So for one phone line, the blue pair should be the correct line to connect to.  However there may be instances where the phone company found a problem with the blue pair and had to use the orange pair instead.  It is possible that there was a problem with all of the pairs going into you house and the phone company had to split between pairs of wires.  When removing the old telephone jacks, take note of which wires are being used on the old jacks.

Rear of phone jack with blue pair attached
The blue pair is connected as the primary telephone line.  The solid blue wire is the “Ring” and gets connected to the red jack terminal.  The white wire with a blue stripe is terminated on the green “Tip” screw.

One pair of wires is used for one telephone line.  The pairs of wires are twisted together to avoid cross talk between telephone lines.  This helps the sound quality.  When looping the bare telephone wire around the terminal screw, loop the wire in the direction that the screw will tighten (Clockwise).  This will cause the loop to close on itself and make a better connection.

Tip +
Ring –

Green

Red

Black

Yellow
Pair 1 White with
blue stripe		 Blue
Pair 2 White with
orange stripe		 Orange
Pair 3 White with
green stripe		 Green
Pair 4 White with
brown stripe		 Brown

 

Here the orange pair is connected as the primary telephone line
Here the orange pair is connected as the primary telephone line.   The solid orange wire is the “Ring” and is connected to the red jack terminal.  The white wire with an orange stripe is terminated on the green “Tip” screw.
The blue pair and orange pair are both connected to the telephone jack.
The blue pair and orange pair are both connected to the telephone jack.  A splitter plugged into the jack will enable the use of two separate telephone lines.   The solid blue wire is the “Ring” and gets connected to the red jack terminal.  The white wire with a blue stripe is terminated on the green “Tip” screw.   The solid orange wire is the “Ring” and is connected to the yellow jack screw.  The white wire with an orange stripe is terminated on the black “Tip” screw.
A telephone jack splitter
A telephone jack splitter enables two lines to be used from one wall jack if two pairs of wires are connected to the terminals in back.
Cat 5e four twisted pair unshielded telephone wire
Cat 5e four twisted pair unshielded telephone wire
Placement of 4 pairs on a jack or a plug
Placement of 4 pairs on a plug or a jack.  For a one pair jack just start in the middle with #4 and #5.

Other wiring diagrams can be found here.

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