What Size Lag Bolts for a TV Mount

TV mounts hang 50–100 lb on a cantilever arm — the lags must bite 2-plus in into solid studs: 5/16 x 3-in lags are the practical default, 3/8 x 3-in for articulating arms and 75-in-plus screens. Never smaller than 1/4 in, always with washers, always into studs — drywall alone never holds a big TV.

What to Look For

  • Default: 5/16 x 3-in lags — most mounts, most TVs.
  • Articulating and 75-in-plus: 3/8 x 3-in — cantilever multiplies load.
  • Minimum 1/4 x 3-in — never smaller, ever.
  • Washers under every head — spreads load, stops pull-through.
  • Pilot 7/32 for 5/16 lag, 1/4 for 3/8 lag — no pilot splits studs.

Top Picks

1. Hillman 5/16 x 3-in zinc lag bolts plus washers Best overall

The TV-mount default — four lags and washers cover nearly every residential install.

Check price on Amazon →

2. Grip-Rite 3/8 x 3-in lag bolts (Grade 5) Big and articulating

Stepped-up diameter for full-motion arms and 75-in-plus panels.

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3. TOGGLER SnapToggle 1/4-20 anchors (4-pack) No-stud fallback

For small TVs where studs cannot be hit — steel channel behind drywall, 100-plus lb rated.

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What to Avoid

Avoid

  • Drywall anchors for big TVs — toggles max out where studs begin.
  • Lags without pilots — split studs hold nothing.
  • Skipping washers — heads pull through mount slots under load.
Bottom line: 5/16 x 3-in into studs covers nearly everything; 3/8-in for arms and giants. Studs first, always.

Also in the toolbox

FAQ

How many lag bolts per TV mount?

Four minimum — two per stud across two studs — for any TV over 40 in or 50 lb. Small fixed mounts sometimes ship with two, but four into two studs is the safe standard; articulating arms want the full pattern torqued evenly.

Can you mount a TV without hitting studs?

Small TVs (under 50 lb) on fixed mounts, yes — with four SnapToggle-style steel toggles rated 100-plus lb each. Anything bigger or articulating needs studs, or a plywood panel spanning two studs that the mount bolts to.

What size pilot hole for 5/16 lag bolts?

7/32-in in softwood studs (pine, fir) — roughly 75 percent of shank diameter. For 3/8-in lags, drill 1/4-in. Too small splits the stud; too large and the threads never bite.

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