License plate screw sizes by manufacturer
Standard and metric license plate screw sizes, what fits which automaker, and which states require a front plate so you know how many you need.
Most US-built vehicles use a 1/4-14 x 3/4 inch self-tapping screw. Most imports use M6 x 20mm or M6 x 16mm. Both are wide enough to fill the slotted holes in a standard 6 x 12 inch plate. If you’ve stripped a hole or your old screws are rusted, that’s the size to ask for at any hardware store.
A few exceptions: Tesla uses an adhesive or tow-eye mount on the front, BMW and most Mercedes use M5 x 12mm in clip-on holders, and some Honda and Acura models use M6 x 20 with a captured washer that’s worth keeping.
By manufacturer
| Make | Standard screw |
|---|---|
| Ford, GM, Stellantis (Chrysler/Dodge/Ram/Jeep) | 1/4-14 x 3/4 in self-tapping |
| Toyota, Lexus, Subaru | M6 x 20mm |
| Honda, Acura | M6 x 20mm |
| Nissan, Infiniti | M6 x 20mm |
| Mazda, Mitsubishi | M6 x 16mm or M6 x 20mm |
| Hyundai, Kia, Genesis | M6 x 20mm |
| Volkswagen, Audi, Porsche | M5 x 20mm or M6 x 12mm (varies by year) |
| BMW, Mini | M5 x 12mm with plastic anchors |
| Mercedes-Benz | M5 x 12mm |
| Volvo | M6 x 16mm |
| Tesla | Front: adhesive bracket. Rear: M6 x 16mm |
If the existing screws came out without splitting the plastic anchor behind them, take one to the hardware store and match it. That’s faster than measuring.
What the numbers mean
The 1/4-14 x 3/4 specification breaks down as a quarter-inch shank diameter, 14 threads per inch, and three-quarters of an inch long. The “14” thread count tells the screw it’s working with sheet metal or plastic, which is what the hidden anchor behind your bumper is.
M6 x 20 means a 6mm shank with standard metric thread pitch, 20mm long. The pitch is usually 1.0mm on automotive plate screws.
Front plate, rear plate, or both
29 states plus DC require both front and rear plates as of 2026. The 21 states that only require a rear plate:
Alabama, Arizona, Arkansas, Delaware, Florida, Georgia, Indiana, Kansas, Kentucky, Louisiana, Michigan, Mississippi, New Mexico, North Carolina, Ohio, Oklahoma, Pennsylvania, South Carolina, Tennessee, West Virginia, and Wyoming.
Ohio became rear-only in 2020, which catches people out. Pennsylvania has been rear-only since 1953. Florida and Tennessee have been rear-only for decades.
If you’re moving to a two-plate state from a one-plate state and your car has no front mounting holes, you’ll need to either drill into the bumper or use an adhesive front plate bracket. Adhesive brackets from CravenSpeed and SnapPlate are popular on sports cars where owners don’t want bumper holes.
Stainless vs. zinc-plated
Zinc-plated screws are cheaper and rust within a few years of road salt exposure. Stainless screws cost a couple dollars more and outlast the car. If you live anywhere with winter salt or coastal humidity, stainless is the better buy. Most auto parts stores stock both.
Black-oxide stainless looks better on dark cars and resists fingerprints. Functionally identical to plain stainless.
When the screw won’t bite
Plastic clips behind the bumper crack and spin in place. If your screw turns forever without tightening, the clip is gone. Replacements: any auto parts store sells universal plate-mounting clips for under $5, or you can use a small zip tie loop in a pinch.
Don’t overtighten. The plate is thin aluminum and the bumper cover is plastic. Snug is enough.