Project Guide

How to Install a Refrigerator Water Line

Plan the Water Line Path
Locating a water supply under the sink to install a refrigerator water line.

Before installing a refrigerator water line, you must carefully plan for it. The water line will have to travel through cabinets or potentially through a hole drilled into the floor, so determining the best water line path ahead of time can help prevent mistakes and unforeseen problems.

  • Your kitchen may already be plumbed for refrigerators with ice and water dispensers. Check around where the refrigerator is placed to see if there is an existing water supply line extending from the wall or up from the floor. If there is a water supply valve already installed behind your fridge, simply connect the supply valve to the refrigerator valve with 1/4-inch water line supply tubing
  • If there isn’t an independent water supply line, you’ll have to use one that feeds the sink or dishwasher. Locate this connection, preferably from a vertical water supply pipe, then map the shortest path from the supply line to the rear of the refrigerator (or where you plan to place the refrigerator). 
  • If needed, plan for the water line to run through cabinets, above storage and behind drawers to prevent damage to the line. 
  • Once you have the approximate length of your preplanned path, plan to add an additional six- to eight-feet of tubing to that measurement so that the water line can coil behind the refrigerator. This extra slack allows the fridge to move so you can clean behind and below it. 
  • Decide what tubing material you want to use for your water supply line. The tubing should have a diameter of 1/4-inch and can be copper line, braided steel line or plastic tubing. Many professionals prefer copper line, but plastic tubing is commonly sold as part of ice maker installation kits.
Cut Off the Water
Shutting off the water supply to begin installing a refrigerator water line.

As with most plumbing projects, you need to turn off the water supply before you begin any installation steps.

  • Shut off the water supply to whichever line you plan to source the water from.  
  • If you are connecting the refrigerator water line to the sink water line, the piping below the sink typically has its own hot and cold shut-off valves. If it doesn’t, you can shut off the main water supply to the house instead.  
  • Turn on the faucet at the sink to allow the line to flush any standing water.
Tap the Water Supply
A person tapping the water supply to install a refrigerator water line.

How to install a refrigerator water line will vary depending on where you plan to tap the water supply in your home.  


If your sink has a shut-off valve, you can tap it using a tee fitting. The tee fitting should fit the threads of your valve, while the third outlet should have an outside diameter of 1/4-inch for the refrigerator water line. 

  • Disconnect the sink water supply line from the cold water shut-off valve by using a wrench or pliers to unscrew the tube’s connection nut. There will be some standing water in the supply line, so prepare to either catch the spillage in a small pan or to soak it up with a sponge. 
  • Attach the tee fitting to the shut-off valve. Tighten the fitting by hand, then secure it further using pliers. 
  • Connect the sink water supply line to the tee fitting. 
  • Connect the refrigerator water line to the third outlet of the tee fitting. 


If your sink does not have a shut-off valve, you will have to tap the line through the sink’s piping and install a valve for the refrigerator water line.


  • Use either a self-tap saddle valve or a tee stop valve. Ensure the valves inlets match the diameter of your pipes and have an outlet with a 1/4-inch outside diameter for the refrigerator water line. 
  • Self-tap saddle valves are often the type of valve included in supply line kits. When using a self-tap saddle valve, attach the valve to the pipe, but do not pierce the pipe until the water line has been connected to the back of the fridge. 
  • When using a tee stop valve, you will have to remove a section of the sink’s water supply pipe. Mark the section you plan to cut. 
  • Cut the section of pipe using pipe cutters and deburr the exterior and interior of the cut pipe ends using a deburring tool or a metal file
  • Securely attach the new valve to both pipe ends. 
  • Read about this process in more detail in our guide How to Install Shut-Off Valves.


If there are no cabinets that run between your sink and refrigerator, you may have to go through the floor or wall to tap the nearest water supply line. 

  • Identify the water supply line you plan to tap and determine where to drill a hole to accommodate the refrigerator water line you will connect. Ensure that whatever path you choose does not disrupt other important wiring or piping. 
  • Drill a 1/4-inch hole to run the tubing through.  
  • Follow the same steps as above to install either a self-tap saddle valve or a tee stop valve. 
Run the Tubing
A person holding tubing to run for a refrigerator water line installation.
  • Uncoil the flexible tubing and begin feeding the tube along the path you planned. 
  • Drill holes as needed through cabinets or through the floor to feed the water line through until you can reach the back of the refrigerator.  
  • Keep the fridge water line from kinking as you complete the run. 
  • For better support, at every two- to three-feet along the water line, use a nylon or cable clamp to secure the line to the cabinet back, or along a floor joist, if applicable. 
Connect the Water Line to the Back of the Refrigerator
A person connecting a water line to a refrigerator.
  • Before you approach how to connect a water line to the back of the fridge, wrap the threads on the water line connection at the back of the refrigerator with sealing tape to ensure a tight seal and prevent leaks. 
  • Attach the end of the water line to the connection point and use a wrench to tighten the nut. 


Tip: Lay down a large piece of cardboard to slide the refrigerator onto when moving it. This will prevent the fridge from scratching your kitchen floors.

Connect the Water Line to the Supply Valve
A person connecting a refrigerator water line.
  • Attach the water line to the 1/4-inch outlet on the water supply valve and tighten the connector nut with a wrench. 
  • If using a piercing valve, once the connection is complete, turn the knob to drive the needle into the pipe and pierce the side, allowing water to flow into the water line. Back the needle out by turning the knob in the opposite direction once the water is flowing. 
Check the Connections
A person checking water line connections for leaks.
  • Double-check all the connections you made. Tighten any connections that need securing. 
Prime the Refrigerator
A person fills a cup with water from a refrigerator water dispenser.
  • If your refrigerator has a water dispenser, run out one or two gallons of water through the new line. Dispose of the water, or you can use it for cleaning or watering plants to avoid wasting it. 
  • If your water line also supplies an ice maker, discard the first two or three batches of ice your refrigerator makes.  

Knowing how to install a refrigerator water line allows you to not only make use of all your refrigerator’s features, but it also allows you to remove and replace your water line for cleaning, ensuring you always have the freshest possible water. Some careful planning and the right tools are all you need to connect a refrigerator water line. If you need help identifying a tool or material, find products fast with image search in The Home Depot app. Snap a picture of an item you like and we'll show you similar products.