How to Install a Pull-Out Drawer Under a Sink

Pull-out drawers transform under-sink storage from a dark, unreachable cavity into functional space you can actually use. Instead of reaching to the back of a cabinet and knocking over bottles, you slide out a drawer on ball-bearing slides and grab what you need. The beauty of this upgrade is that it doesn't require plumbing work—you're building around existing pipes, not moving them. Done right, your drawer will glide smoothly for years and give you back several cubic feet of usable storage. The real skill here is measuring twice and installing the slides dead-level. If your slides aren't square to the cabinet, the drawer will bind or hang up mid-stroke. We'll walk you through securing the slides, building or sourcing the drawer box, and testing everything before you load it with cleaning supplies.

1. Measure your cabinet opening and plan your drawer. Empty the under-sink cabinet completely and remove any existing shelving. Measure the width, depth, and height of the opening in three places (left, center, right) to account for out-of-square cabinets. Your drawer should be roughly 1–2 inches narrower than the cabinet width and 2–3 inches shorter than the opening height. Note where your water supply lines and drain trap sit—your drawer box must fit around them, not over them.
2. Secure the slides to the cabinet sides. Slide rails come in pairs (left and right). They mount on the inside of your cabinet walls at the height where you want your drawer to sit—typically 4–6 inches above the cabinet floor. Use a level to mark a horizontal line on both sides of the cabinet at your chosen height. Drill pilot holes through the mounting holes in each slide using a drill bit slightly smaller than your wood screws. Screw the slides firmly to the cabinet sides, ensuring they are perfectly level and parallel to each other.
3. Install the drawer box runners on the drawer itself. Most ball-bearing slides come as a four-piece assembly: two outer rails (mounted to the cabinet) and two inner runners (mounted to your drawer box). Attach the inner runners to the inside of your drawer box sides using the supplied screws, positioned to match the height and angle of the cabinet slides. Make sure the runners are parallel to each other and square to the front of the drawer. Test-fit the drawer by sliding the runners into the cabinet rails; it should slide smoothly without binding.
4. Build or fit your drawer box around the plumbing. Your drawer box can be plywood, melamine, or pre-made drawer units. Measure the interior dimensions you need, then build or cut your box so it's slightly smaller than the opening—aim for a quarter-inch gap on all sides. If water lines or the trap run through your space, cut notches or holes in the drawer bottom and sides to let the plumbing pass through freely. Smooth any rough edges with sandpaper. Attach the inner runners to the sides of your completed drawer box.
5. Slide the drawer onto the cabinet rails and test the fit. Carefully align the drawer runners with the cabinet rails and slide the drawer all the way in until it seats fully. Slide it back out to its full extension—it should move smoothly with no grinding, binding, or tilting. The drawer should sit level and not sag to one side. If it binds, stop and check that both cabinet rails are truly parallel and level; use shims under the slide feet if needed. Test the extension and retraction five times with the drawer empty before loading it.
6. Install drawer stops and soft-close hardware if needed. Most full-extension slides include built-in stops that prevent the drawer from sliding completely out of the cabinet and crashing to the floor. Check that these stops are engaged and working. If you want soft-close operation, add soft-close dampers to the sides of the drawer (sold separately)—they slow the drawer's return to a gentle close instead of slamming. Screw them into the pre-drilled holes on the cabinet rails.
7. Seal plumbing gaps and load your drawer. If your drawer cuts around plumbing, wrap foam pipe insulation around the exposed supply lines and seal any gaps with waterproof silicone caulk or expanding foam. Let caulk cure for 24 hours before running water. Once cured, load your drawer with cleaning supplies, dish soaps, and other under-sink items. Test one more time that the drawer slides smoothly when loaded—don't overstuff, or you'll add drag and wear on the slides.