diff --git a/usr.bin/mkimg/gpt.c b/usr.bin/mkimg/gpt.c
--- a/usr.bin/mkimg/gpt.c
+++ b/usr.bin/mkimg/gpt.c
@@ -208,6 +208,9 @@
 				idx++;
 			}
 		}
+		if (part->index + 1 == active_partition) {
+			le64enc(&ent->ent_attr, GPT_ENT_ATTR_BOOTME);
+		}
 	}
 	return (tbl);
 }
diff --git a/usr.bin/mkimg/mkimg.1 b/usr.bin/mkimg/mkimg.1
--- a/usr.bin/mkimg/mkimg.1
+++ b/usr.bin/mkimg/mkimg.1
@@ -22,7 +22,7 @@
 .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 .\"
-.Dd June 8, 2020
+.Dd February 8, 2024
 .Dt MKIMG 1
 .Os
 .Sh NAME
@@ -157,8 +157,9 @@
 option marks a partition as active, if the partitioning
 scheme supports it.
 Currently, only the
+.Ar gpt and
 .Ar mbr
-scheme supports this concept.
+schemes support this concept.
 By default,
 .Nm
 will only mark the first partition as active when boot code is