Trailer Pin Locks (Locking Hitch Pins)

Updated October 2026 · How we make money

Our top picks

Best valueMaster Lock 2866DAT

Master Lock 2866DAT

Fits 1/2 and 5/8 in receivers.

About $19 (masterlock.com list)

Check price at Master Lock ↗
Best universal with sleeveTrimax TS32

Trimax TS32

Fits 1/2 and 5/8 in with sleeve.

Check current price

Check price at Trimax ↗
Best heavy-dutyAMPLock

AMPLock

Custom-fit range for many coupler types.

Check current price

Check price at AMPLock ↗
Quick answer: A trailer pin lock replaces the ordinary hitch pin and clip with a pin that locks. Measure your pin diameter (1/2 in for 1-1/4 in receivers, 5/8 in for 2 in and larger) and the span across the receiver. The Master Lock 2866DAT (about $19) covers both 1/2 and 5/8 in; the Trimax TS32 does the same with a sleeve.
Illustration of a locking hitch pin through a receiver and ball mount
Illustration of a locking hitch pin through a receiver and ball mount (TrailerLock illustration).

Comparison

LockBest forFitsPrice (approx.)
Master Lock 2866DATBest value1/2 in and 5/8 in receivers; 2-3/4 in usable pin lengthAbout $19 (masterlock.com list)Check price ↗
Trimax TS32Best universal with sleeve1/2 in and 5/8 in receivers (with sleeve)Check current priceCheck price ↗
AMPLock (coupler, gooseneck, kingpin, hitch, latch pin, door locks)Best heavy-dutyCoupler (boat, RV, cargo), gooseneck (Bulldog, Atwood), kingpin, hitch 1-1/4 to 3 in, latch pin, barn/roll-up doorCheck current priceCheck price ↗

How we chose: picks are based on published specifications, materials, fit charts, manufacturer information and patterns in owner reports. We have not lab-tested these locks. Prices are approximate list prices seen on maker sites in October 2026 and change often.

Our picks in detail

Master Lock 2866DAT
Best value

Master Lock 2866DAT

Who it is for: Most trucks with 1-1/4 or 2 in receivers.

Pros
  • Fits 1/2 and 5/8 in receivers
  • Rated up to Class III/IV, 10,000 lb (5/8 in)
  • Weather seal and cap
Cons
  • Only protects the hitch, not an unhitched trailer
  • 2-3/4 in span too short for some receivers
Key specs

5/8 in pin rated Class III/IV, 10,000 lb; 1/2 in Class I/II, 3,500 lb.

Check price at Master Lock ↗
Trimax TS32
Best universal with sleeve

Trimax TS32

Who it is for: Owners with more than one receiver size.

Pros
  • Fits 1/2 and 5/8 in with sleeve
  • Stainless version available
  • Keyed-alike sets
Cons
  • Price not confirmed on our check
Key specs

Trimax T5 pin (5/8 in, 3-1/2 in span) fits Class V hitches.

Check price at Trimax ↗
AMPLock
Best heavy-duty

AMPLock (coupler, gooseneck, kingpin, hitch, latch pin, door locks)

Who it is for: Owners who want custom-fit security and a fit-finder.

Pros
  • Custom-fit range for many coupler types
  • 5-year warranty with registration
  • Fit quiz on maker site
Cons
  • Prices not confirmed on our check
  • Heavy
Key specs

5-year warranty with registration (per maker).

Check price at AMPLock ↗

Measuring for a pin lock

  1. Pull the existing pin and measure its diameter.
  2. Measure the usable length across the outside of the receiver.
  3. Choose a lock with at least that span (the 2866DAT has 2-3/4 in usable length; Trimax T5 has 3-1/2 in for Class V).

Latch pins vs hitch pins

A coupler latch pin lock is a small lock that goes through the latch hole on your coupler so it cannot be opened. It is not the same as a receiver hitch pin. See trailer latch locks.

Keyed-alike tip

Many brands sell keyed-alike sets (coupler lock plus pin lock). Proven offers keyed-alike across its range; Trimax keys many locks alike. One key is easier at a boat ramp at dawn.

Our pick

Master Lock 2866DAT: best value. Most trucks with 1-1/4 or 2 in receivers. If budget matters more, see the other picks above.

Check price at Master Lock ↗

FAQs

What size is a standard hitch pin?
5/8 in for most 2 in receivers; 1/2 in for 1-1/4 in receivers.
Will a pin lock rust?
Look for a weather cap and stainless or plated steel; lubricate the cylinder a few times a year.
Do I need a pin lock if I have a coupler lock?
They protect different things: the pin lock protects the hitched setup, the coupler lock the unhitched trailer.

Related guides

Best Trailer Hitch LocksHeavy-Duty Trailer Hitch LocksTrailer Latch Locks