Drywall Anchors Guide: Toggle Bolts, Molly Bolts, and Self-Drilling Anchors

Plastic Expansion Anchors

Plastic expansion anchors (the kind that come with curtain rod hardware) are the weakest drywall anchor. A plastic sleeve goes into a pre-drilled hole, and a screw driven into the sleeve forces it to expand outward against the drywall. They hold 15 to 25 pounds in 1/2-inch drywall, which is enough for small picture frames and light switch plates.

For anything heavier than a small picture frame, skip plastic anchors entirely. They are the default included in hardware packages because they are cheap, not because they are effective. The failure mode is gradual — the anchor slowly enlarges the hole until one day the load drops.

If you use them, match the drill bit to the anchor size exactly. A hole that is too large lets the anchor spin without gripping. A hole that is too small cracks the drywall when you push the anchor in. The packaging specifies the drill bit size — use it.

Self-Drilling Anchors

Self-drilling (or self-tapping) drywall anchors have a pointed, threaded shank that screws directly into drywall without a pre-drilled hole. Metal self-drilling anchors hold 50 to 75 pounds. They are the best general-purpose anchor for medium-weight items — towel bars, small shelves, light fixtures, and curtain rod brackets.

Drive them in with a Phillips screwdriver or a drill on low speed. The threads cut into the drywall and create a secure grip. Then drive the mounting screw into the center of the anchor. The wide threads distribute the load across more drywall than a simple expansion anchor.

Zinc or steel self-drilling anchors outperform plastic ones. The metal body resists deformation under load and the sharper threads cut cleaner holes. Nylon self-drilling anchors exist but hold less and can crack during installation if the drywall is old or brittle.

Removal is straightforward — unscrew the mounting screw, then unscrew the anchor itself. The hole left behind is larger than a simple screw hole but patches easily with spackle. This removability makes self-drilling anchors a good choice for renters who need to patch holes when moving out.

Toggle Bolts and Snap Toggles

Toggle bolts are the strongest drywall anchor. A spring-loaded toggle passes through a hole in the drywall, opens on the backside, and distributes load across 3 to 4 inches of the back surface. A 1/4-inch toggle bolt in 1/2-inch drywall holds 90 to 150 pounds. A 3/8-inch toggle bolt exceeds 200 pounds.

The drawback of traditional toggle bolts is the installation hole — it must be large enough for the folded toggle to pass through, which means a 3/4-inch or larger hole for most sizes. If you remove the bolt, the toggle falls inside the wall and you cannot reuse it. You also cannot remove and reinsert the bolt without losing the toggle.

Snap toggles (also called strap toggles or toggle anchors) solve both problems. A metal channel passes through the hole, a plastic strap holds it against the backside, and you snap off the excess strap. The bolt can be removed and reinstalled without losing the anchor. The installation hole is smaller than a traditional toggle bolt.

Use toggle bolts or snap toggles for anything heavy — TV mounts, heavy shelves, grab bars, full-length mirrors, and heavy artwork. For TV mounts specifically, snap toggles are preferred because you may need to remove and reattach the TV multiple times.

Choosing the Right Anchor

Weight is the primary factor. Under 15 pounds (small frames, switch plates): plastic expansion anchors are fine. 15 to 50 pounds (medium frames, light shelves, towel rings): self-drilling metal anchors. 50 to 150 pounds (heavy shelves, TV brackets, curtain rods with heavy drapes): toggle bolts or snap toggles. Over 150 pounds: find a stud.

A stud finder eliminates the need for anchors entirely when a stud is available at the right location. A screw into a wood stud holds hundreds of pounds. If you are mounting something heavy and the stud location does not quite line up, use a combination — one side screwed into a stud and the other side on a toggle bolt.

Wall material matters. Standard 1/2-inch drywall is what anchor ratings assume. If your walls are 5/8-inch (common in fire-rated construction and ceilings), anchors hold slightly more. If your walls are older plaster over lath, use toggle bolts — they grip the lath on the backside. Plastic anchors do not work well in plaster because plaster cracks rather than compressing around the anchor.

For ceiling-mounted items, derate all anchor ratings by 50% compared to wall ratings. Gravity works directly against the anchor in a ceiling mount. A toggle bolt rated for 150 pounds in a wall should hold no more than 75 pounds on a ceiling. For anything heavy on a ceiling — fans, heavy light fixtures, plant hangers — always use a structural ceiling box attached to a joist.

Frequently Asked Questions