Sig Sauer · P365 family

Sig Sauer P365 XL

The original optic-ready P365 at full length: one RMSc-pattern cut across every current SKU, and no compensator to shorten the barrel under it.

Specifications

ModelP365 XL

Slide length3.7"

Barrel length3.7"

Integrated compensatorNo

Factory capacity12+1

Grip module familyp365xl

Optic cutRMSc

Which optic cut does it have?

The cut is set per SKU, not per model, so the suffix on the box matters. This is read from the same fitment data the guides below use.

All current SKUsRMSc

Fit guides

Every optic in these lists is verified against this model’s factory cut, with prices checked against retailer feeds.

Fit guideRed Dots that fit the P365 XLVerified list, live prices →

Magazines that fit your P365 XL

What the maker says fits this model, and how each magazine sits in the grip. A baseplate that extends below the grip adds no rounds: capacity is always shown on its own.

P365X/XL 9mm 10rd Flush Magazine

Capacity 10 rounds

Flush fit — Factory flush magazine for the P365X, P365-XL and XL COMP

MSRP $49.99Buy from Sig Sauer ↗

AMAG 12 SG9 P365 9mm 12rd Magazine

Capacity 12 rounds

Flush fit — Flush with the included X/XL floorplate

Not available in: CA, CT, DC, HI, MA, MD, NJ, NY, RI, WA

Check priceBuy at OpticsPlanet ↗

P365/X/XL 9mm 12rd Magazine

Capacity 12 rounds

Flush fit — Factory magazine for the P365X and P365-XL

Not available in: CA, CT, DC, HI, MA, MD, NJ, NY, RI, WA

Check priceBuy at OpticsPlanet ↗

AMAG 15 SG9 P365 9mm 15rd Magazine

Capacity 15 rounds

Fits with an included part — Fit the included X/XL grip extension

Not available in: CA, CT, DC, HI, MA, MD, NJ, NY, RI, WA

Check priceBuy at OpticsPlanet ↗

P365/X/XL 9mm 15rd Magazine

Capacity 15 rounds

Fits with an included part — Swap to the included P365X / P365-XL baseplate; extends below the grip

Not available in: CA, CT, DC, HI, MA, MD, NJ, NY, RI, WA

MSRP $49.99Buy from Sig Sauer ↗

AMAG 17 SG9 P365 9mm 17rd Magazine

Capacity 17 rounds

Fits with an included part — Fit the included X/XL grip extension

Not available in: CA, CO, CT, DC, HI, IL, MA, MD, NJ, NY, RI, VT, WA

Check priceBuy at OpticsPlanet ↗

P365 9mm 17rd Magazine (All 9mm Models)

Capacity 17 rounds

Fits with an included part — Swap to the included P365X / P365-XL floor plate; extends below the grip

Not available in: CA, CO, CT, DC, HI, IL, MA, MD, NJ, NY, RI, VT, WA

$64.49Buy at OpticsPlanet ↗

TTI SIG X-MACRO Completed Magazine w/ Versatile Basepad

Capacity 20 rounds

Fits, extends below the grip — MACRO-length body with a +3 basepad; extends below the grip

Not available in: CA, CO, CT, DC, DE, HI, IL, MA, MD, NJ, NY, RI, VT, WA

$71.99Buy at OpticsPlanet ↗

P365 9mm 21rd Magazine

Capacity 21 rounds

Fits, extends below the grip — Works, but leaves a gap between the baseplate and the shorter grip (per SIG)

Not available in: CA, CO, CT, DC, DE, HI, IL, MA, MD, NJ, NY, RI, VT, WA

$71.49Buy at OpticsPlanet ↗

Doesn’t fit the P365 XL: AMAG 10 SG9 P365 9mm 10rd Magazine, P365 9mm 10rd Finger Extension Magazine, P365 9mm 10rd Flush Magazine

Prices update from retailer feeds; a listing we could not verify in the last 7 days shows “Check price”. Gunforma may earn a commission on retailer links. Links to a maker's own store earn us nothing.

Browse parts

Parts by category →Real builds →Other P365 models →

Last reviewed 2026-10-02