The Glock 43X and the SIG Sauer P365 are the two most recommended slim carry pistols on the market. They compete directly for the same buyer: someone who wants a concealable 9mm with enough capacity and shootability to be a serious defensive firearm rather than a last-resort pocket gun. Both are excellent. The choice between them comes down to your priorities.
Specs Compared
| Spec | Glock 43X | SIG P365 |
|—|—|—|
| Caliber | 9mm | 9mm |
| Barrel Length | 3.41 in | 3.10 in |
| Overall Length | 6.50 in | 5.80 in |
| Height | 4.41 in | 4.30 in |
| Width | 1.10 in | 1.06 in |
| Weight (unloaded) | 18.70 oz | 17.80 oz |
| Standard Capacity | 10 rounds | 10 rounds |
| MSRP | ~$499 | ~$599 |
Both are thin — under 1.10 inches wide. Both carry 10+1 rounds standard, with extended magazines available for each. The P365 is slightly smaller in every dimension except grip width, where the difference is negligible.
Glock 43X: The Case For
Shootability. The 43X has a longer grip and barrel than the P365, which translates to better recoil control and a more natural shooting experience. Shooters who have trained extensively on full-size and compact Glocks find the 43X transition intuitive — same manual of arms, same muscle memory.
Aftermarket ecosystem. The Shield Arms S15 magazine is a significant development: it gives the 43X 15 rounds of 9mm in the same frame that originally held 10. This is a substantial capacity upgrade that does not exist for the P365 in the same way. The broader Glock aftermarket — holsters, sights, triggers, lights — is also mature and deep.
Price. The 43X carries a lower MSRP than the P365 and is frequently discounted. Street prices are often $420-460 for the standard version.
Reliability record. The Glock platform has an established multi-decade reliability record. The 43X is a newer design, but it runs on the same action that has proven itself across millions of service pistols.
SIG P365: The Case For
Size. The P365 is genuinely smaller, and in deep concealment applications that margin matters. Printing is less likely with a shorter, lighter pistol, especially for smaller-framed carriers. The P365 was designed specifically around the question: what is the smallest pistol that is still genuinely shootable?
Capacity at size. The original P365 was notable precisely because it fit 10 rounds in a package smaller than most 7-round single-stack pistols. That engineering achievement — high capacity in a small frame — remains the P365’s core identity.
Trigger. Most shooters find the P365’s trigger marginally better out of the box than the 43X’s. It is a personal preference point, but it comes up consistently in head-to-head comparisons.
Optics integration. The P365 X-Macro and P365-XRAY3 variants offer optics-ready options. SIG’s Romeo Zero optic was designed specifically for the platform. The optics ecosystem for P365 has grown significantly.
The Real Tradeoffs
Choose the Glock 43X if:
- You already train on Glocks and want consistent manual of arms across your carry and home defense guns
- Aftermarket capacity upgrades matter to you (Shield Arms S15 magazines)
- You prioritize shootability over minimum footprint
- Budget is a consideration
Choose the SIG P365 if:
- Minimum size and weight are your primary criteria
- You carry in warm climates or light clothing where every millimeter of print matters
- You want the most purpose-built EDC design on the market
- You are not already invested in the Glock ecosystem
What Neither Does Well
Both pistols are harder to shoot accurately than a full-size or compact pistol. The short grip, short barrel, and light weight mean felt recoil is sharper and follow-up shots require more discipline. Neither is ideal as your only training gun. If you carry one of these, consider training regularly on a G19 or G17 and treating the slim-line gun as a deployment-specific tool.
The Honest Bottom Line
If you shoot Glocks and want a consistent platform: 43X. If you are buying your first slim-line carry gun and want maximum engineering toward concealability: P365. Neither decision is wrong, and both pistols will serve you well if you train with them.
Shop both options: Brownells carries both the Glock 43X and SIG P365 with current pricing. For slim IWB holsters for either pistol, search kydex appendix holsters on Amazon.
Sources:
- SIG Sauer P365 specifications — sigsauer.com
- Glock 43X specifications — glock.com
- Shield Arms S15 magazine compatibility — shieldarms.com
- Lucky Gunner, slim 9mm carry pistol comparison data, 2023