SIG SAUER M18

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55 documented listings108 fit unconfirmedBrowse categories ↓

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What the compatibility labels mean

How we knowHow we check compatibility

Lab testedFit checked by Firearm Lab for the recorded setup.
Documented fitmentSupported by manufacturer, partner, or reviewed community evidence.
Interface matchMounting details match, but this exact model and part have not been confirmed to fit together.

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Model details

Manufacturer

SIG SAUER

Model & version

M18

Mounting details

MIL-STD-1913 Picatinny, Leupold DeltaPoint Pro, SIG SAUER P320 PRO optic cut (ROMEO1PRO / DPP pattern, P320 / M17 / M18 / AXG slides)

Compatibility records

163

Lights & rail fitment

Lights & Lasers

63 listed

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Optics & footprint adapters

Optics

25 listed

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Optic Plates

23 listed

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Sights

17 listed

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Triggers & internals

Triggers

9 listed

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Takedown levers

1 listed

GoGun USA
Gas Pedal Assist - Thumb Rest for Sig P320 X5, X10, M17, M18, AXG, P250 (All Generations)
Manufacturer documented

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Recoil Springs

1 listed

Armory Craft
Sig P320 COMPACT - M18 - P320 Legion X-Carry - P320 AXG Recoil Tuning Kit
Manufacturer documented

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Grip & magwells

Extended Magazine Releases

1 listed

Armory Craft
Extended Magazine Release Button: P250 / P320
Manufacturer documented

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Base Pads

3 listed

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Magazines

6 listed

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Also on this pistol

Holsters

9 makers

Alien Gear Holsterschecked 2026-11-01
Blackhawkchecked 2026-11-01
Bravo Concealmentchecked 2026-11-01
DeSantis Gunhidechecked 2026-11-01
Galcochecked 2026-11-01
Safarilandchecked 2026-11-01
Tenicorchecked 2026-11-01
Tier 1 Concealedchecked 2026-11-01
We The People Holsterschecked 2026-11-01

Check each manufacturer’s options for your model, light and optic.

Holster makers (9)

Barrels & comps

Barrels

2 listed

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Compensators

2 listed

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Slides

1 listed

Grey Ghost Precision
GGP320 Compact Slides
Manufacturer documented

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Categories with no listings (4)

About the SIG SAUER M18

Type: Pistol
Manufacturer: SIG SAUER
Model & version: M18
Caliber: 9mm
Mounting details: MIL-STD-1913 Picatinny, Leupold DeltaPoint Pro, SIG SAUER P320 PRO optic cut (ROMEO1PRO / DPP pattern, P320 / M17 / M18 / AXG slides)
Width: 1.6"
Height: 5.5"
Weight: 28.1 oz
Barrel length: 3.9"
Overall length: 7.2"

Lights & Lasers

EPL Duty (Black)

P.ID

APLc (Universal)

PL350G3 OKWv2 Light Package

Optics

RXS-100 Reflex Sight

EFLX CE Pistol Optic

SCS-320

DeltaPoint Pro

Optic Plates

SIG P320 M17/M18 ACRO Mount Plate

SIG P320 Legion (M17 / M18) w/ R1P/DPP Cut to Trijicon RMR / RMR HD / SRO / Holosun 407C / 507C / 507Comp / 508T / C&H EDC-XL / COMP / COMP MAX / Olight Osight X w/ Dovetail for GLOCK compatible sights

Red Dot Mount – MRA for Sig Sauer Civilian P320-M17/M18

Optic Mount for Sig Sauer P320 Pro Cut Slides

Sights

OPTICS READY STEALTH SERIES FOR SIG SAUER

REAR SIGHT ASSY, P320, X-RAY3, SIGHT PLATE, SIGHT SCREWS, BLK

RMR Mount w/ Integrated Bright & Tough Night Sights - SIG Sauer M17/M18 Commercial Variant

SUPPRESSOR HEIGHT SIGHTS FOR SIG SAUER

Triggers

SIG P320 COMPATIBLE DROP IN TRIGGER

P320 Adjustable Hybrid Trigger

Sig Sauer P320 Trigger Kit

TITANIUM SIG P320 COMPATIBLE DROP IN TRIGGER

Takedown levers

Gas Pedal Assist - Thumb Rest for Sig P320 X5, X10, M17, M18, AXG, P250 (All Generations)

Recoil Springs

Sig P320 COMPACT - M18 - P320 Legion X-Carry - P320 AXG Recoil Tuning Kit

Extended Magazine Releases

Extended Magazine Release Button: P250 / P320

Base Pads

NDZ Magazine Floor Base Plate for Sig Sauer P320 P250 9mm .357 .40 Cerakote Burnt Bronze

NDZ Magazine Floor Base Plate for Sig Sauer P320 P250 9mm .357 .40 Cerakote Tungsten

NDZ Magazine Floor Base Plate for Sig Sauer P320 P250 9mm .357 .40 Including X Series HCFDE

Magazines

A2-320 17-Round

P211/P320 FULL/CARRY 9MM 23RD EXTENDED MAGAZINE

P250, P320 FULL/CARRY/M17 9MM 17RD MAGAZINE

P250,P320 9MM 30RD EXTENDED MAGAZINE

Holsters

Barrels

Sig Sauer M18 Compact 9MM Match 3.9"

Sig Sauer M18 Compact 9MM Match 3.9" with 1/2×28 suppressor threads (4.55" OAL)

Compensators

Sig Sauer Compensators - for 9mm P320 & P226, P228, P229, P225/P6

PMM Barrel and Compensator Combos for Sig P320

Slides

GGP320 Compact Slides

About the SIG SAUER M18