Glock magazine compatibility: which magazines fit which models

Glock magazines follow one rule: a longer magazine fits a shorter pistol of the same caliber family, and a shorter magazine does not fit a longer one. Within that rule there are families that do not mix, generation changes that matter for left-handed shooters, and single-stack pistols with their own magazines. This chart sorts all of it by caliber so you can buy the right magazine the first time.

The rule

A Glock magazine locks into the frame on a notch cut in the magazine body. A longer magazine from the same caliber family seats in a shorter frame and simply protrudes below the grip; a shorter magazine cannot reach the catch in a longer frame and falls out. So a Glock 17 magazine works in a 19 and a 26, a 19 magazine works in a 26, and a 26 magazine works only in a 26. The same logic runs through every double-stack caliber. Frame width is the other limit: the standard-width 9mm, .40 and .357 SIG families share a magazine well width and the large-frame 10mm and .45 ACP families share a wider one, but neither crosses into the other.

9mm double stack

Glock 26 magazine, 10 rounds: fits the 26 only.
Glock 19 magazine, 15 rounds: fits the 19 and 26. Not the 17, 19X, 45 or 47, whose frames are taller.
Glock 17 magazine, 17 rounds: fits the 17, 17L, 34, 19, 26, 19X, 45, 47 and 49.
19-round magazine: the 17 body with a taller floorplate, shipped with the 19X and 45; fits everything the 17 magazine fits.
24 and 33-round magazines: fit every 9mm double-stack Glock, protruding well below the grip.
10-round restricted versions of the 17 and 19 magazines fit the same pistols as their full-capacity versions.

.40 S&W and .357 SIG

The .40 and .357 SIG families share the standard frame and their magazines interchange with each other, since the two cartridges share a case head and the magazines are dimensionally the same. The 27 and 33 magazines (9 rounds) fit only the subcompacts; the 23 and 32 magazines (13 rounds) fit the compacts and subcompacts; the 22, 31, 35 and 24 magazines (15 rounds) fit every .40 and .357 SIG double stack; the 22-round extended magazine fits all of them. A 9mm magazine will not feed .40 and should not be used in a converted pistol; use 9mm magazines with a 9mm conversion barrel.

10mm and .45 ACP large frame

The 20, 29 and 40 MOS share 10mm magazines: the 29 magazine (10 rounds) fits the 29 only, the 20 magazine (15 rounds) fits the 20, 29 and 40. The 21, 30 and 41 share .45 ACP magazines the same way: 30 magazine (10 rounds) in the 30 only, 21 magazine (13 rounds) in all three. The 30S, the slim-slide version of the 30, takes 30 magazines. The single-stack Glock 36 has its own 6-round magazine that fits nothing else, and no other .45 magazine fits it.

.45 GAP

The 37, 38 and 39 use their own .45 GAP magazines in the standard-width frame: 39 magazine (6 rounds) in the 39, 38 magazine (8 rounds) in the 38 and 39, 37 magazine (10 rounds) in all three. They are not interchangeable with .45 ACP magazines.

.380 ACP

The Glock 42 is a slimline pistol with its own 6-round .380 magazine that fits only the 42. The Glock 25 and 28, the compact and subcompact .380 double stacks, use their own .380 magazines: the 28 magazine (10 rounds) fits the 28, the 25 magazine (15 rounds) fits both. They do not accept 9mm magazines.

Slimline 9mm

The 43 uses a 6-round magazine that fits only the 43. The 43X and 48 share a 10-round magazine that fits both and does not fit the 43. Slimline magazines are single stack and fit no double-stack Glock; no double-stack magazine fits a slimline. Aftermarket steel 15-round magazines for the 43X and 48 exist and require a steel magazine catch. The extensions guide covers slimline options.

.22 LR

The Glock 44 uses its own 10-round .22 LR magazine, a hybrid polymer and steel design with a load-assist button. Nothing else fits it and it fits nothing else.

Gen 4 and Gen 5 changes

Gen 4 introduced a reversible magazine catch, so Gen 4 and later magazines have a catch notch on both sides. They work in every earlier pistol. Older single-notch magazines work in a Gen 4 or Gen 5 with the catch in the standard right-side position; if you reverse the catch for left-handed use, only double-notch magazines will lock in. Gen 5 magazines add an orange follower and a floorplate with an extended front lip for the flared magazine well, and they work in every earlier pistol of their caliber. The subcompact 26, 27, 33 and 39 Gen 5 pistols have a slightly different floorplate to fit their new grip.

Aftermarket compatibility

Magpul PMAG GL9 magazines follow the same rules as factory 9mm magazines: the 15-round fits 19 and 26, the 17, 21 and 27-round fit every 9mm double stack, and the 10 and 12-round fit the 26. Magpul's magazines have double notches. ETS magazines follow the same pattern and add 22 and 31-round versions. Magazines made for aftermarket Glock-pattern carbines and pistols usually follow Glock 17 dimensions.

Quick check before you order

Match the caliber family: 9mm, .40 or .357 SIG, 10mm, .45 ACP, .45 GAP, .380, slimline, .22.
Match the frame height: a magazine from a pistol the same size or larger.
Left-handed with the catch reversed: double-notch magazines only.
State capacity limit: see magazine laws by state.

Browse Glock magazines by model, and read magazine care to keep them running.

General information, not legal advice. Current as of September 2026. Laws change; check the official source before you act.