How to Install Soft Close Drawer Slides: Complete Step-by-Step Guide

Soft close drawer slides are one of the most satisfying upgrades you can make to your kitchen or bathroom cabinets. Instead of drawers slamming shut, they glide closed with a gentle, cushioned motion. The good news? Installing them is a straightforward DIY project that most homeowners can complete in an afternoon.

What Are Soft Close Drawer Slides?

Soft close drawer slides use a hydraulic damping mechanism built into the slide assembly. When you push the drawer closed, the damper engages in the last few inches of travel, slowing the drawer to a smooth, silent close. This protects your cabinets, reduces noise, and adds a premium feel to any piece of furniture.

How the Soft Close Mechanism Works

The damping mechanism contains a small piston that moves through hydraulic fluid. As the drawer approaches the closed position, a catch engages the piston, forcing it through the fluid and creating resistance. The speed of closing is controlled by the viscosity of the fluid and the size of the piston orifice. Most modern soft close slides are rated for 50,000 cycles or more.

Types of Soft Close Slides

There are two primary types of soft close drawer slides:

• Side mount slides attach to the sides of the drawer box and the interior sides of the cabinet. They are the most common type and the easiest to install. Ball-bearing side mount slides typically support 75–100 pounds.
• Undermount slides attach beneath the drawer bottom and to the cabinet sides. They are hidden from view when the drawer is open, providing a cleaner look. Undermount slides typically support 50–75 pounds and require a more precise installation.

Tools and Materials You'll Need

• Soft close drawer slides (matched to your drawer length)
• Tape measure
• Pencil
• Level
• Square
• Drill/driver with Phillips bit
• Screws (usually included with slides)
• Optional: drawer slide mounting jig

How to Measure for Replacement Drawer Slides

Accurate measurement is the most critical step. Incorrect measurements lead to slides that bind, sag, or don't close properly.

Measuring Drawer Width and Depth

Remove the existing drawer and measure the interior width of the cabinet opening from side to side. For side mount slides, you need approximately 1/2 inch of clearance on each side (1 inch total). If your cabinet opening is 14 inches wide, your drawer box should be about 13 inches wide.

Measure the depth of the cabinet from the face frame to the back wall. Drawer slides come in standard lengths: 12, 14, 16, 18, 20, 22, and 24 inches. Choose the longest slide that fits within your cabinet depth, leaving about 1 inch of clearance behind the slide.

Choosing the Right Slide Length

Full extension slides allow the drawer to extend completely out of the cabinet, giving you access to the entire drawer. Three-quarter extension slides are less expensive but only extend about 75% of the way. For kitchen drawers, full extension is almost always worth the small price premium.

Step-by-Step Installation for Side Mount Slides

1. Separate the slide components. Most slides consist of two pieces: the cabinet member (the wider piece) and the drawer member (the narrower piece). Pull the drawer member out and press the release lever to separate them.
2. Mark the cabinet. Measure up from the bottom of the cabinet to where you want the center of the slide. Use a level to draw a horizontal line. Most replacement installations should match the position of the old slides.
3. Attach the cabinet member. Align the front of the cabinet member flush with the front edge of the face frame. Drive screws through the front mounting hole first, check for level, then secure the remaining screws. Use the slotted holes for fine adjustment later.
4. Attach the drawer member. Position the drawer member on the bottom edge of the drawer side, flush with the front of the drawer box. Secure with screws through the front hole first, then the rear.
5. Slide the drawer in. Align the drawer members with the cabinet members and push the drawer in until it clicks into place.
6. Test and adjust. Open and close the drawer several times. The soft close mechanism should engage smoothly in the last 2–3 inches of travel.

Step-by-Step Installation for Undermount Slides

1. Install the cabinet brackets. Undermount slides typically use rear-mounting brackets that attach to the back of the cabinet and front locking clips. Install the rear bracket first, then the slide rail.
2. Attach locking clips to the drawer. Undermount slides use small plastic or metal clips that screw into the underside of the drawer box at the front corners. Position them according to the manufacturer's template.
3. Mount the slide rails. Secure the slide rails to the cabinet sides using the provided screws. The rails should be level and parallel.
4. Hang the drawer. Position the drawer above the slides, align the rear pins with the rear brackets, and press down until the front clips engage with a click.
5. Adjust. Most undermount slides allow three-way adjustment: up/down, left/right, and front/back. Use these to ensure the drawer front is perfectly aligned with adjacent drawers and cabinet doors.

Adjusting Soft Close Drawer Slides

Fixing Alignment Issues

If the drawer sits crooked or rubs on one side, loosen the screws in the slotted mounting holes and shift the slide slightly. For undermount slides, use the built-in adjustment screws — typically accessible from the front of the cabinet when the drawer is removed. A quarter turn can make a significant difference.

Adjusting Closing Speed

Some premium soft close slides have an adjustable damping feature. Look for a small dial or screw on the damper mechanism. Turning it clockwise usually increases resistance (slower close), while counterclockwise decreases it. If your slides don't have this feature, the closing speed is preset and cannot be modified.

Common Installation Mistakes to Avoid

• Not checking for square. If your cabinet isn't square, the slides will bind. Use shims to correct any racking before installing slides.
• Using the wrong screw length. Screws that are too long can poke through the cabinet side. Screws that are too short won't hold. Stick with the screws included in the package.
• Ignoring the clearance gap. Side mount slides need exactly 1/2 inch per side. Even 1/16 inch off can cause problems.
• Skipping the front screw first. Always start with the front mounting hole to establish alignment, then work your way back.
• Forgetting to check level. Even a slight tilt will prevent the soft close mechanism from working correctly and cause the drawer to drift open or closed on its own.

Frequently Asked Questions

Can I add soft close to existing drawer slides? Yes — you can purchase soft close adapters that retrofit onto standard ball-bearing slides. They attach to the back of the cabinet and provide a damping catch. This is a good option if your current slides are in good condition.

How much do soft close drawer slides cost? Side mount soft close slides typically cost $8–$20 per pair. Undermount slides range from $20–$50 per pair. Premium brands like Blum and Grass may cost more but offer superior durability and smoother action.

What weight can soft close slides support? Most standard soft close slides are rated for 75–100 pounds. Heavy-duty versions can handle 150 pounds or more, suitable for large tool drawers or file cabinets.

Do soft close slides work on any drawer? Soft close slides work on most standard drawer boxes. However, the drawer box must be properly sized for the slides. If you're replacing old wooden center-guide slides, you may need to modify the drawer or build a new drawer box.