Telephone wires are easy to work with and very safe due to the low voltages involved.
The most complex part of installing telephone wires is complying with the defined standards.
When installing additional telephone wires into an existing facility, it is usually best to determine which telephone wiring standard is currently in use and conform to that standard.
When installing telephone wiring into a new facility, EIA/TIA T586A is the standard to utilize.
How the Wire Gets into a Residence
Historically, telephone companies ran telephone wires above ground with telephone poles to make wire issues easy to repair. The wire itself is sourced at a telephone company and goes through various paths to get into a home’s general vicinity.
Above Ground Wiring
In older neighborhoods (1970s and earlier in the US) and areas that have a high water table, telephone wiring is most likely above ground. There is one or more telephone poles in easement areas in the neighborhood that distribute phone service wire pairs to residences with an aerial connection method. A breakout box is attached to the pole, with the main service lines for the area entering in one side and residential lines running out of the other side. Wires are then run from the breakout boxes to each neighborhood residence.
Underground Wiring
Most modern U.S. neighborhoods have telephone wiring underground. During the neighborhood build out, before home building commences, breakout boxes are installed in geographically strategic points and lines are trenched back to the neighborhood’s primary distribution can and to each property nearby.
The Residential Network Interface Device
Regardless of how the wire is run to a house, the wire terminates on a Network Interface Device (NID), which is connected to the home. This device is a gray or tan box about eight inches wide and twelve inches long with a door(s) concealing two compartments. Access to the customer compartment is possible with a simple slot headed screw. A specialized screw head controls access to the telco compartment. Users can open the NID’s customer access compartment to check lines for a dial tone, check wiring connections inside the NID, and to trace lines coming out of the NID into the home. The user does not need to open the NID’s telco compartment. If there is a wiring fault between a house and the central office, the customer cannot repair it. Most NIDs handle up to 5 different lines.
The telephone line from the pole or breakout box goes into the telco compartment and exits through the customer compartment.
If the customer only has one telephone line and there has been no maintenance on the line for a long while, he/she may have a box that is a predecessor to the NID. This box is simply a plastic or metal cover that is screwed over a telephone wiring box to protect it from the elements. The telephone company will replace the old box with a new NID at no cost if there is time, available equipment, and the customer demonstrate a need such as a method to test for dial tone. Sometimes, phone company technicians leave the original box in place and just install an NID between the box and the wiring running to the pole or breakout box.

Testing Phone Lines
Always use a previously tested corded phone for phone line testing. This is the only way to be sure that only the phone line is being tested. If unsure about the test phone’s functionality, take it over to a neighbor or family members home and test it with a known good phone line. Once there is dial tone, the phone is usable for a line test.
First Just Pick Up the Phone
When the telephone company initially installs a phone line into a home, they should provide at least one phone jack to connect a telephone. The easiest phone service test is to merely plug a phone into this jack with the proper wire, take the phone off the hook, and listen for the dial tone. Some people may need to consult their phone manual.
No Dial Tone
If there is no dial tone when the phone is taken off the hook, there is probably a phone line problem. If there are multiple jacks in the home, test each one to verify which jacks work and which do not. If some of the jacks are functional and others are not, the wiring fault is between the NID and those specific jacks. The phone company may be willing to help with these problems for a charge. Read more on how to repair these problems in the “Repair” sections below. If none of the jacks in the home is working, test the phone lines at the NID.
Testing at the NID
When the NID’s customer compartment is opened, there are phone jacks lined up, usually vertically. For each phone line installed in a house, there is a phone jack with a line plugged into it. Do not worry if there are jacks that have no line plugged into them, it may be that there was a second line to that home at one time, that the wiring box was faulty, or that they just installed more than one wiring box and jack as a standard install. If there is more than one line, labels on the NID lid should tell which jack is associated with which phone line or number. If they do not, just try them all until the one to be tested is found. To test, disconnect the line from the jack and plug the corded phone into it. This will disconnect the line from the jacks in the house, so do not panic if there is no dial tone inside. If there is a dial tone when the phone is hooked up, the wiring fault is in the house. If there is no dial tone, call the phone company for repair, nothing further can be done to fix the problem.
Sometimes the Wire Colors Do Not Match
Many phone companies have updated their color standards due to the use of Cat 5 cable for most phone line installs and to keep residential and business installs in line with each other. In this new standard, there are no green, red, black, or yellow wires. White/blue, blue/white, white/orange, and orange/white wires have replaced them. Knowing how to identify the wire color is a simple matter. The wire is going to be primarily one color, with small stripes of a secondary color on it. If the wire is primarily orange with white stripes then that color is orange/white. The following simple table will help users to understand which colors match. The NID labels will most likely have the old coloring scheme on them and most telephone wiring components for sale will still reflect the original colors.
| Function | New Color | Old Color |
|---|---|---|
| Tip 1 | Green | White/Blue |
| Ring 1 | Red | Blue/White |
| Tip 2 | Black | White/Orange |
| Ring 2 | Yellow | Orange/White |
New Telephone Jacks in the Home
Installing new telephone jacks in a home is really simple, but there are some tools and basic hardware needed to perform the install.
Tools:
- Drill
- Drill bits
- Flathead Screwdriver
- Fish tape
- Cable Test Equipment
Hardware
Most hardware, electronics, and many grocery and department stores have the items needed to complete an installation.
Modular jack boxes come in two variants, one with a wiring box and one without. If installing an entirely new jack, get the jack box with the wiring box. Users only need a jack box without a wiring box when replacing a jack box that is damaged, but the wiring box inside is still intact. There are both four and six contact modular jacks available. Buy a four contact modular jack unless there is a special reason to buy a six contact modular jack. This process needs one jack box for each new jack to be installed.
Buy four wire flat silver satin telephone wire for any new jacks in the home. Users may save a little money if they only buy the individual wires without the silver sheath. However, having the sheath will save time and frustration in the long run. Wires with sheaths are flexible, can easily be stripped off in locations that require it, and keep the wires together so they can easily be placed where needed.
If there are more than two lines in the home and jacks for all of them will be placed in the same location, six or eight conductor telephone wires can be used as well. Keep in mind that there are three pairs of wire: a blue pair, an orange pair, and a green pair in six conductor wire. Eight conductor wire has the same wiring colors as the six conductor, it just adds a brown pair for the last pair. Connect the same wires to the proper posts on the wiring block to avoid any problems.
- Modular jack boxes with wiring box
- Four, six, or eight strand telephone wire
Always Have a Corded Phone for Emergencies
Customers may need to plug a phone or phone base into house power if they have a cordless phone or a phone with an integrated answering machine (or some other capability). Standard corded phones receive all the necessary power over the phone line itself, so no additional power is required. It is always a good plan to have a corded phone just in case the other devices have issues or to use in emergencies when house power is out.
General Reference Information
The information following may help users understand the standards and wire plans in their home. They are merely reference materials to assist with planning and diagnostics.
The Christmas and Halloween Standard for Telephone Wiring
Many homes have only 2 pairs (4 wire) of telephone wiring.
The first telephone line is connected to the Christmas pair. This wire pair is called the Christmas pair because one wire is Green and the other is Red.
In the Christmas pair, the Green wire is Tip and the Red wire is Ring.
The second telephone line is connected to the Halloween pair. This wire pair is called the Halloween pair because one wire is Black and the other wire is Yellow.
In the Halloween pair, the Black wire is Tip and the Yellow wire is Ring.
The EIA/TIA 568B Standard for Telephone Wiring
| Pin (Jack) | Pin (Plug) | Color | Pair |
|---|---|---|---|
| 1 | 8 | White/Orange | Tip 2 |
| 2 | 7 | Orange | Ring 2 |
| 3 | 6 | White/Green | Tip 3 |
| 4 | 5 | Blue | Ring 1 |
| 5 | 4 | White/Blue | Tip 1 |
| 6 | 3 | Green | Ring 3 |
| 7 | 2 | White Brown | Tip 4 |
| 8 | 1 | Brown | Ring 4 |
The EIA/TIA 568A Standard for Telephone Wiring
| Pin (Jack) | Pin (Plug) | Color | Pair |
|---|---|---|---|
| 1 | 8 | White/Green | Tip 3 |
| 2 | 7 | Green | Ring 3 |
| 3 | 6 | White/Orange | Tip 2 |
| 4 | 5 | Blue | Ring 1 |
| 5 | 4 | White/Blue | Tip 1 |
| 6 | 3 | Orange | Ring 2 |
| 7 | 2 | White Brown | Tip 4 |
| 8 | 1 | Brown | Ring 4 |
The USOC (Universal Service Order Code) 8 Wire Standard for Telephone Wiring
| Pin (Jack) | Pin (Plug) | Color | Pair |
|---|---|---|---|
| 1 | 8 | White/Brown | Tip 4 |
| 2 | 7 | White/Green | Tip 3 |
| 3 | 6 | White/Orange | Tip 2 |
| 4 | 5 | Blue | Ring 1 |
| 5 | 4 | White/Blue | Tip 1 |
| 6 | 3 | Orange | Ring 2 |
| 7 | 2 | Green | Ring 3 |
| 8 | 1 | Brown | Ring 4 |
The USOC (Universal Service Order Code) 6 Wire Standard for Telephone Wiring
| Pin (Jack) | Pin (Plug) | Color | Pair |
|---|---|---|---|
| 1 | 6 | White/Green | Tip 3 |
| 2 | 5 | White/Orange | Tip 2 |
| 3 | 4 | Blue | Ring 1 |
| 4 | 3 | White/Blue | Tip 1 |
| 5 | 2 | Orange | Ring 2 |
| 6 | 1 | Green | Ring 3 |
The 25 pair Telephone Wiring Standard
| Pin (Jack) | Pin (Plug) | Color | Pair |
|---|---|---|---|
| 1 | 50 | Blue/White | Ring 1 |
| 2 | 49 | Orange/White | Ring 2 |
| 3 | 48 | Green/White | Ring 3 |
| 4 | 47 | Brown/White | Ring 4 |
| 5 | 46 | Slate/White | Ring 5 |
| 6 | 45 | Blue/Red | Ring 6 |
| 7 | 44 | Orange/Red | Ring 7 |
| 8 | 43 | Green/Red | Ring 8 |
| 9 | 42 | Brown/Red | Ring 9 |
| 10 | 41 | Slate/Red | Ring 10 |
| 11 | 40 | Blue/Black | Ring 11 |
| 12 | 39 | Orange/Black | Ring 12 |
| 13 | 38 | Green/Black | Ring 13 |
| 14 | 37 | Brown/Black | Ring 14 |
| 15 | 36 | Slate/Black | Ring 15 |
| 16 | 35 | Blue/Yellow | Ring 16 |
| 17 | 34 | Orange/Yellow | Ring 17 |
| 18 | 33 | Green/Yellow | Ring 18 |
| 19 | 32 | Brown/Yellow | Ring 19 |
| 20 | 31 | Slate/Yellow | Ring 20 |
| 21 | 30 | Blue/Violet | Ring 21 |
| 22 | 29 | Orange/Violet | Ring 22 |
| 23 | 28 | Green/Violet | Ring 23 |
| 24 | 27 | Brown/Violet | Ring 24 |
| 25 | 26 | Slate/Violet | Ring 25 |
| 26 | 25 | White/Blue | Tip 1 |
| 27 | 24 | White/Orange | Tip 2 |
| 28 | 23 | White/Green | Tip 3 |
| 29 | 22 | White/Brown | Tip 4 |
| 30 | 21 | White/Slate | Tip 5 |
| 31 | 20 | Red/Blue | Tip 6 |
| 32 | 19 | Red/Orange | Tip 7 |
| 33 | 18 | Red/Green | Tip 8 |
| 34 | 17 | Red/Brown | Tip 9 |
| 35 | 16 | Red/Slate | Tip 10 |
| 36 | 15 | Black/Blue | Tip 11 |
| 37 | 14 | Black/Orange | Tip 12 |
| 38 | 13 | Black/Green | Tip 13 |
| 39 | 12 | Black/Brown | Tip 14 |
| 40 | 11 | Black/Slate | Tip 15 |
| 41 | 10 | Yellow/Blue | Tip 16 |
| 42 | 9 | Yellow/Orange | Tip 17 |
| 43 | 8 | Yellow/Green | Tip 18 |
| 44 | 7 | Yellow/Brown | Tip 19 |
| 45 | 6 | Yellow/Slate | Tip 20 |
| 46 | 5 | Violet/Blue | Tip 21 |
| 47 | 4 | Violet/Orange | Tip 22 |
| 48 | 3 | Violet/Green | Tip 23 |
| 49 | 2 | Violet/Brown | Tip 24 |
| 50 | 1 | Violet/Slate | Tip 25 |
Telephone Wiring Pin Number Orientation
When looking at a telephone jack, Pin 1 is the left most pin.
When looking at a telephone plug, Pin 8 is the right most pin.
Telephone Wiring Jacks and Plugs
In telephone wiring, the plug is the male end of a telephone cable and the jack is the female receptacle in the wall.
Telephone Wiring Tip and Ring
The terms Tip and Ring are used extensively when discussing telephone wiring.
Tip is the electrically positive wire and Ring is the electrically negative wire.

I have to move my intercom buzzer, which is connected to a first floor phone, one and a half metres because of a new porch I’m having built. It is an easy d.i.y job but I’m unable to find the 2 metres of cable I need – even online. It doesn’t help that I don’t know what this cabling is called. The wires are green, yellow, red, black, blue and white. Can anyone help, please.
I have zero knowledge about phones. We are building a house and it’s time to finish up. The phone wire that was installed has 6 wires, the phone jack I have to put on the wall has only 4. do I have the wrong jack? Do I leave 2 wires not connected? Help!
I have/had 4 working phone jacks, none of them close to my computer with internet so I had to run my ethernet wire across two rooms. Well, we finally got around to installing a new jack and oh the excitement when plugging in the phone to test it first and it worked. Then plugging in my DSL and router and have it work was a dream, until, that is, a day later I noticed I wasn’t getting any phone calls and upon checking the other four connections, they no longer work? How can this be?
The same thing happened to me. I had to put filters on all of the phone jacks for them to work. The filters just plug into the phone jack and you plug the phone into the filter. Solved the problem.
I have no knowledge of phones system. I’m replacing an old phone system and just purchased 8 new AT&T Phones (1040′s) and the wiring coming into the bld is 6 pin and the new phone’s and wires with the phones are 4 pin. Is there a conversion coupler available for easy installation or do I have to have the entire bld rewired. Advice or directions is appreciated..
We just moved into our house which is about 30 years old. The phone jacks have been pulled out so all I have is the wire coming out. The wires are orange, red, blue and white; the jacks we have (the wires were previously connected to these same jacks) indicate white, black, yellow and red. Where do I connect which wire?
Thanks! I appreciate helpful info and free! Mainly because of budget issues. Also, I am a do-it- yourselfer.
How do I wire a six line phone system from a cable company
tip/ring router. There will be 5 voice lines and one fax. seven corded phone locations
Can you use the same entry point as an electrical cable. eg in the same hole as the electrical cable in a wall cavity.
We moved our phone line to another room by disconnecting the phone jack and running the wire through the wall. We are trying to reconnect the phone jack and the wires are different colors. I am in trouble for not writing the color connections down before I removed the jack. Phone line is orange, blue, white/blue and white/orange; phone jack is red, green, yellow and black. Can you tell me which colors to match up?
Wire to jack hook up is White/blue = Green
Blue Red
White/orange = Black
Orange Yellow
Unless you have 2 lines working at the same location (ie 2 seperate telephone numbers) you probably don’t need to hook up the White – Orange to the jack, particularly if the jack is the end of the wire run.
Hi
Can you help?
I have a master socket which is working ok. There is also an extension socket, which i intend to use for my Sky box. I was looking to move this, and undid the front plate, and all the wires fell out as i undid the screws. The wires colours i have are: White, Orange, Black & Green. I do not need the ringer part of the extension. I have tried umpteen different configurations, but cannot get it to work – Help!
We have a master socket in the hallway, directly next to this is a standard socket. From the standard socket we have a telephone extension for phone and internet. We also have a connection going to the sky box. All of this is basically piggy backing from the one connection. All the equipment works fine, however, the wiring is a mess and can be knocked easily. This configuration must be 10 years old and I was wondering if there is a simple way of tidying using a single socket / box, i.e. direct wiring?? Cheers
I am a 1099 IT Contractor. I have been doing some business phone installs and repairs for various companies as Spencer Technology and Granite Technology in my local area in NC. I am more of a Data tech, computer tech, MCSE and CCNA. I have trying to find more info in finding more about working with the old land lines and not just VoIP.
I added onto my old house, contractor left me to wire up the new phone wires to the old phone box on the out side of my house. The old phone box has line one and line 2 with line one colors wired all red and line two wired all green. (yellow and black not used.) The new addition was wired up with new wire that has different colored wires. green/white, blue/white, orange/white ,brown/white. which of these wire would go to the red line one and which wire would go to green?. thanks jimmy
any pair will be fine. Also polarity is not an issue. Usually blue/blue striped is used for phone…. orange pair for second line and green for data….
I have a really old tel. extension on wainscotting. The braided wire goes into 2 screw terminals. Both wires are black. How do I connect a modern jack (I want to plug in an answering machine) to this?
hello there I’m trying to wire my mums phone line and internet, its the oblong box inside the house that i’m trying to wire which connects to the square box were the phone is inserted. Anyhow the oblong box only has plain colours (not stripped) and I have no idea where they go. Theres 8 wires red green black etc and 8 places where they can be screwed into E.g the oblong box. I hope u understand me, I’m retarded when it comes to explaining things, sorry. Can you please let me know which one go’s where. keeleytomorrow@yahoo.co.uk
Thanks
De plug in de hoorn was stuk, heb toen het snoer rechtstreeks verbonden met de bedrading in de hoorn. heb kiestoon. De gebelde persoon kan mij horen maar ik hoor de persoon niet. wel hoor ik mijn eigen stem in de luispreker van de hoorn. Wat is hier verkeerd?
gr. Rud
Need help. I try to have DSL install to my second unit on the back. There had not yet any phone jack to my unit yet. How do I install a new phone line to my unit, do I have to call the Phone company to install a new phone line from the pole or can I run an phone line from the NID of the fron unit? I would like to DIY if posible to save some money.. Please help. Thanks
Happy New Year.
I’m having trouble with blocked local calls.Do you think there may be trouble with wiring in phone box outside house?How can I fix that?
Thanks immensely!
What are warehouses for ?