What Size Screws Does Your TV Wall Mount Need?

Part of our complete guide: How to Mount a TV on Any Wall.

It is the question that stops a Saturday install dead. The bracket is on the wall, the TV is face-down on the bed, and none of the bolts in the little bag look like they belong to it. The answer is simpler than it feels, but it starts with a point most people get wrong: a TV mount needs two completely different sets of hardware, and neither one substitutes for the other.

1. Two Sets of Screws That Have Nothing in Common

The TV side uses metric machine screws that thread into inserts molded into the back of the set. They are short, fine-threaded and carry the screen's weight in shear. The wall side uses lag bolts driven into framing, and those carry the whole load of screen and bracket together, pulling outward.

Mixing them up is how screens come down. A machine screw has no business in a wall and a lag bolt will not fit a television, and the fact that both arrive in the same box is the only thing they share. Work on them as two separate jobs and the whole thing gets easier.

2. The TV Side Is Metric, and There Are Only a Few Sizes

Television mounting holes follow the VESA standard, which means metric threads — you will meet M4, M5, M6 and M8 and almost nothing else. Smaller screens generally take the smaller two and larger screens the larger two, but that is a tendency rather than a rule, and plenty of sets break it.

So do not guess from screen size. The manual states it, the mount's own chart usually lists it, and a test fit settles it in seconds: a bolt that threads in two turns by hand with no force is the right diameter, and one that needs persuading is not. Our guide to what to look for in a TV wall mount covers the rest of what a kit should contain.

3. Length Matters More Than Diameter

Getting the diameter right only tells you the bolt will turn. Length is what decides whether it holds, and this is where real damage happens. Too short and the threads barely engage, so the bracket is relying on a few millimeters of plastic. Too long is worse: the bolt bottoms out against the chassis inside the set and feels perfectly tight while the bracket is still loose against the back.

On some sets a long bolt can reach something behind the rear panel that it should never touch. The rule we work to is that a bolt should engage fully and stop, with the bracket pulled flat against the back of the television and no gap. If it hits bottom before the bracket is snug, it is the wrong length, not something to crank harder.

4. Spacers, and the Back That Is Not Flat

Plenty of televisions do not have a flat back. The inserts sit in a recess, or the panel curves away, or a cable channel runs right where the arm wants to sit. That is what the plastic or metal spacers in the kit are for, and leaving them out is one of the most common mistakes we find on somebody else's install.

• Recessed inserts. The arm has to clear the surrounding housing, so the spacer stacks behind the arm before the bolt goes through.
• Curved or tapered backs. Without spacers the arm touches at one point and the bolt pulls at an angle, which is how inserts strip.
• Thin washers. If a bracket slot is wider than the bolt head, the washer is structural, not decorative. It is what stops the head pulling through.
• Model-specific brackets. Some very slim sets want their maker's own plate, which our guide to LG OLED wall mounting goes into.

5. Those Inserts Strip Easily

The threaded inserts in a television are shallow and set in plastic, and an impact driver will ruin one in under a second. Hand tools only on the TV side, and stop the moment it goes firm. There is no torque spec worth chasing here: snug and square is the whole target.

If an insert does strip, the screen is not scrap, but it is no longer a job to improvise on, because the remaining three are now carrying more than they were designed for. That is the point to get someone to look at it rather than finding a longer bolt.

6. The Wall Side: Structure, Not Drywall

Lag bolts into solid framing are what hold a mount up, and length is again the thing that matters: the bolt has to pass through the drywall and still reach real depth in the stud behind it. A longer screw into nothing is not an upgrade. Use the washers, and drill the pilot hole the mount's instructions ask for, because a lag driven dry into hardwood framing can snap the lag or split the stud.

What should never appear on the wall side is an ordinary drywall screw, a deck screw or anything black and brittle from the bottom of the drawer. Those are made to clamp, not to hang weight off, and they shear. When there is no stud where the TV needs to go, that is a different problem with a proper answer — see our guide to mounting a TV on drywall with no studs rather than reaching for longer anchors.

7. When the Mount Came With No Hardware

Secondhand mounts, online returns and the bracket that moved house in a box of cables all tend to arrive incomplete. The honest answer is not to substitute what looks close. A bolt one size down rattles in the hole, and one a thread pitch off will start and then bind.

If you are reusing a plate you already own, our guides to reusing a TV wall mount and dismounting and remounting when you move cover what is worth keeping and what is not. If you would rather we just bring the right hardware, that is included.

Pricing

Installation is priced by screen size: 32" $129, 43" $129, 50" $129, 55" $129, 65" $139, 75" $229 and 85" $279. Every installation covers mounting the TV, leveling, basic cable management, and all wall hardware. The mount itself is separate — flat $35, tilting $45, full-motion $125 (32–55") — or bring your own. Soundbar mounting is $40, in-wall cable concealment is $99, smart TV setup is $35 and a powerline adapter setup is $99. Service within 20 miles of Lexington is free. Richmond is our home base, so it is free too.

Wall hardware being part of the price is not a small thing. It means we turn up with lag bolts sized for what is actually behind your wall, and with the spacers and washers for your particular set, rather than hoping the bag in the box is complete. If you already have a mount and are not sure the hardware is all there, say so when you call and bring it out when we arrive — a mount that fits gets used at no charge.