Westminster Effects is a handwired guitar pedal builder founded in 2015 by Cody Fields and based in Lyman, South Carolina. The company operates as a small one-person shop, with pedals assembled by hand from the founder's workspace. Its branding draws on Reformed church history — product names like the 1689 Overdrive and the Geneva Amp Sim reference historical confessions and theological figures — reflecting the owner's roots in the worship music community.

The catalog spans overdrive, distortion, fuzz, delay, reverb, modulation, compression, boost/preamp, and bass-specific effects. Notable pedals include the Puritan British Overdrive, the Piper Drive booster/overdrive, the Osteen Distortion, the Geneva Amp Sim, and the 2716 Seth Morrison Distortion signature pedal. The brand also produces a DI series and bass-oriented variants of several circuits.

While Westminster Effects developed an initial following among worship guitarists, its pedals are used across a range of styles from cover bands to metal. Distribution is primarily direct through its website and Reverb, with dealer availability through retailers such as Cumberland Guitars, Guitar Center, and Danny D's Guitar Hacienda.

Westminster Effects has 14 products cataloged on Equipboard, including Boost Effects Pedals, Overdrive Effects Pedals, and Distortion Effects Pedals.