diff --git a/sys/cddl/boot/zfs/zfsimpl.h b/sys/cddl/boot/zfs/zfsimpl.h
index d3ae3c32635d..b14a829025d1 100644
--- a/sys/cddl/boot/zfs/zfsimpl.h
+++ b/sys/cddl/boot/zfs/zfsimpl.h
@@ -904,6 +904,16 @@ typedef enum pool_state {
 	POOL_STATE_POTENTIALLY_ACTIVE	/* Internal libzfs state	*/
 } pool_state_t;
 
+/*
+ * Send TRIM commands in-line during normal pool operation while deleting.
+ *	OFF: no
+ *	ON: yes
+ */
+typedef enum {
+	SPA_AUTOTRIM_OFF = 0,
+	SPA_AUTOTRIM_ON,
+} spa_autotrim_t;
+
 /*
  * The uberblock version is incremented whenever an incompatible on-disk
  * format change is made to the SPA, DMU, or ZAP.
diff --git a/usr.sbin/makefs/makefs.8 b/usr.sbin/makefs/makefs.8
index e165702813ae..47c7bf50df5a 100644
--- a/usr.sbin/makefs/makefs.8
+++ b/usr.sbin/makefs/makefs.8
@@ -33,7 +33,7 @@
 .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 .\" POSSIBILITY OF SUCH DAMAGE.
 .\"
-.Dd August 12, 2026
+.Dd October 7, 2026
 .Dt MAKEFS 8
 .Os
 .Sh NAME
@@ -535,6 +535,15 @@ The following keywords are supported:
 The base-2 logarithm of the minimum block size.
 Typical values are 9 (512B blocks) and 12 (4KB blocks).
 The default value is 12.
+.It Cm autotrim
+The value of the
+.Ql autotrim
+pool property, either
+.Ql on
+or
+.Ql off .
+The default is
+.Ql off .
 .It Cm bootfs
 The name of the bootable dataset for the pool.
 Specifying this option causes the
diff --git a/usr.sbin/makefs/tests/makefs_zfs_tests.sh b/usr.sbin/makefs/tests/makefs_zfs_tests.sh
index 22adfda00d2b..fe27c62ab765 100644
--- a/usr.sbin/makefs/tests/makefs_zfs_tests.sh
+++ b/usr.sbin/makefs/tests/makefs_zfs_tests.sh
@@ -107,6 +107,64 @@ autoexpand_cleanup()
 	common_cleanup
 }
 
+#
+# Test setting the autotrim pool property.
+#
+atf_test_case autotrim cleanup
+autotrim_body()
+{
+	local src val
+
+	create_test_inputs
+
+	atf_check -s exit:1 -e match:"invalid value .foo. for autotrim" \
+	    $MAKEFS -s 1g -o rootpath=/ -o poolname=$ZFS_POOL_NAME \
+	    -o autotrim=foo $TEST_IMAGE $TEST_INPUTS_DIR
+
+	for val in on off; do
+		atf_check $MAKEFS -s 1g -o rootpath=/ \
+		    -o poolname=$ZFS_POOL_NAME \
+		    -o autotrim=$val \
+		    $TEST_IMAGE $TEST_INPUTS_DIR
+
+		import_image
+
+		check_image_contents
+
+		# OpenZFS reports a pool property whose value equals the
+		# default as coming from the default, even if it was set.
+		if [ $val = off ]; then
+			src=default
+		else
+			src=local
+		fi
+		atf_check -o inline:$val\\n \
+		    zpool get -H -o value autotrim $ZFS_POOL_NAME
+		atf_check -o inline:$src\\n \
+		    zpool get -H -o source autotrim $ZFS_POOL_NAME
+
+		atf_check zpool destroy ${ZFS_POOL_NAME}
+		atf_check rm -f ${TEST_ZFS_POOL_NAME}
+		atf_check mdconfig -d -u $(cat ${TEST_MD_DEVICE_FILE})
+		atf_check rm -f ${TEST_MD_DEVICE_FILE}
+	done
+
+	# Without the option the property keeps its default value.
+	atf_check $MAKEFS -s 1g -o rootpath=/ -o poolname=$ZFS_POOL_NAME \
+	    $TEST_IMAGE $TEST_INPUTS_DIR
+
+	import_image
+
+	atf_check -o inline:off\\n \
+	    zpool get -H -o value autotrim $ZFS_POOL_NAME
+	atf_check -o inline:default\\n \
+	    zpool get -H -o source autotrim $ZFS_POOL_NAME
+}
+autotrim_cleanup()
+{
+	common_cleanup
+}
+
 #
 # Test with some default layout defined by the common code.
 #
@@ -1110,6 +1168,7 @@ T_flag_mtree_cleanup()
 atf_init_test_cases()
 {
 	atf_add_test_case autoexpand
+	atf_add_test_case autotrim
 	atf_add_test_case basic
 	atf_add_test_case compression
 	atf_add_test_case dataset_removal
diff --git a/usr.sbin/makefs/zfs.c b/usr.sbin/makefs/zfs.c
index 1288c52141ab..9e304202fb4f 100644
--- a/usr.sbin/makefs/zfs.c
+++ b/usr.sbin/makefs/zfs.c
@@ -82,6 +82,8 @@ zfs_prep_opts(fsinfo_t *fsopts)
 	memset(zfs, 0, sizeof(*zfs));
 
 	const option_t zfs_options[] = {
+		{ '\0', "autotrim", &zfs->autotrim, OPT_STRPTR,
+		  0, 0, "Automatic TRIM (on or off)" },
 		{ '\0', "bootfs", &zfs->bootfs, OPT_STRPTR,
 		  0, 0, "Bootable dataset" },
 		{ '\0', "mssize", &zfs->mssize, OPT_INT64,
@@ -247,6 +249,17 @@ zfs_check_opts(fsinfo_t *fsopts)
 	if (zfs->vdevpath[0] != '/')
 		errx(1, "path `%s' must be absolute", zfs->vdevpath);
 
+	zfs->autotrimval = SPA_AUTOTRIM_OFF;
+	if (zfs->autotrim != NULL) {
+		if (strcmp(zfs->autotrim, "on") == 0)
+			zfs->autotrimval = SPA_AUTOTRIM_ON;
+		else if (strcmp(zfs->autotrim, "off") == 0)
+			zfs->autotrimval = SPA_AUTOTRIM_OFF;
+		else
+			errx(1, "invalid value `%s' for autotrim",
+			    zfs->autotrim);
+	}
+
 	if (zfs->ashift == 0)
 		zfs->ashift = 12;
 
@@ -262,6 +275,7 @@ zfs_cleanup_opts(fsinfo_t *fsopts)
 	zfs = fsopts->fs_specific;
 	free(zfs->rootpath);
 	free(zfs->vdevpath);
+	free(zfs->autotrim);
 	free(zfs->bootfs);
 	free(__DECONST(void *, zfs->poolname));
 	STAILQ_FOREACH_SAFE(d, &zfs->datasetdescs, next, tmp) {
@@ -474,6 +488,9 @@ pool_init_objdir_poolprops(zfs_opt_t *zfs, zfs_zap_t *objdir)
 	zap_add_uint64(objdir, DMU_POOL_PROPS, id);
 
 	zfs->poolprops = zap_alloc(zfs->mos, dnode);
+
+	if (zfs->autotrim != NULL)
+		zap_add_uint64(zfs->poolprops, "autotrim", zfs->autotrimval);
 }
 
 /*
diff --git a/usr.sbin/makefs/zfs/zfs.h b/usr.sbin/makefs/zfs/zfs.h
index 13f2ece43c69..ebc54caad8e9 100644
--- a/usr.sbin/makefs/zfs/zfs.h
+++ b/usr.sbin/makefs/zfs/zfs.h
@@ -80,6 +80,8 @@ typedef struct {
 	const char	*poolname;
 	char		*rootpath;	/* implicit mount point prefix */
 	char		*vdevpath;	/* vdev path, pool property */
+	char		*autotrim;	/* "on" or "off", pool property */
+	spa_autotrim_t	autotrimval;	/* parsed autotrim value */
 	char		*bootfs;	/* bootable dataset, pool property */
 	int		ashift;		/* vdev block size */
 	uint64_t	mssize;		/* metaslab size */