diff --git a/cmd-swap-pane.c b/cmd-swap-pane.c
index 7dc6a4358..a97e33da1 100644
--- a/cmd-swap-pane.c
+++ b/cmd-swap-pane.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: cmd-swap-pane.c,v 1.55 2026/07/15 13:02:33 nicm Exp $ */
+/* $OpenBSD: cmd-swap-pane.c,v 1.56 2026/10/02 12:23:44 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -182,9 +182,15 @@ cmd_swap_pane_exec(struct cmd *self, struct cmdq_item *item)
 			window_set_active_pane(src_w, tmp_wp, 1);
 		}
 	} else {
+		/*
+		 * Keep the same pane active, unless the swap has covered it
+		 * with a zoomed pane: activating it would hide the zoom. With
+		 * -Z the zoom moves to the active pane afterwards instead.
+		 */
 		if (src_w->active == src_wp)
 			window_set_active_pane(src_w, dst_wp, 1);
-		if (dst_w->active == dst_wp)
+		if (dst_w->active == dst_wp &&
+		    (args_has(args, 'Z') || window_pane_is_visible(src_wp)))
 			window_set_active_pane(dst_w, src_wp, 1);
 	}
 	if (src_w != dst_w) {
diff --git a/regress/swap-pane.sh b/regress/swap-pane.sh
new file mode 100644
index 000000000..8002a6189
--- /dev/null
+++ b/regress/swap-pane.sh
@@ -0,0 +1,286 @@
+#!/bin/sh
+
+# swap-pane swaps positions: the layout cell (and so floating or tiled), the
+# geometry, and the zoomed and hidden state belong to the position and stay
+# behind. Check this within a window and across windows.
+
+PATH=/bin:/usr/bin
+TERM=screen
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+TMUX="$TEST_TMUX -LtestA$$ -f/dev/null"
+trap '$TMUX kill-server 2>/dev/null' 0
+trap 'exit 1' 1 2 15
+
+fail()
+{
+	echo "$*" >&2
+	exit 1
+}
+
+run()
+{
+	$TMUX "$@" || fail "failed: $*"
+}
+
+# check <pane> <expected floating:zoomed:hidden:window>
+check()
+{
+	got=$(run display-message -p -t "$1" \
+	    '#{pane_floating_flag}:#{pane_zoomed_flag}:#{pane_hidden_flag}:#{window_index}') || exit 1
+	[ "$got" = "$2" ] || fail "$3: $1 got '$got', expected '$2'"
+}
+
+# checkwin <window> <expected window_zoomed_flag:window_panes> <label>
+checkwin()
+{
+	got=$(run display-message -p -t "$1" \
+	    '#{window_zoomed_flag}:#{window_panes}') || exit 1
+	[ "$got" = "$2" ] || fail "$3: window $1 got '$got', expected '$2'"
+}
+
+# checkgeom <pane> <expected WxH+X+Y> <label>
+checkgeom()
+{
+	got=$(run display-message -p -t "$1" \
+	    '#{pane_width}x#{pane_height}+#{pane_left}+#{pane_top}') || exit 1
+	[ "$got" = "$2" ] || fail "$3: $1 geometry got '$got', expected '$2'"
+}
+
+# checkactive <window> <expected pane> <label>
+checkactive()
+{
+	got=$(run display-message -p -t "$1" '#{pane_id}') || exit 1
+	[ "$got" = "$2" ] || fail "$3: window $1 active got '$got', expected '$2'"
+}
+
+# The layout has to survive being read back, which catches a cell that no
+# longer matches its pane.
+checklayout()
+{
+	l=$(run display-message -p -t "$1" '#{window_layout}') || exit 1
+	run select-layout -t "$1" "$l"
+	got=$(run display-message -p -t "$1" '#{window_layout}') || exit 1
+	[ "$got" = "$l" ] || fail "$2: layout of $1 changed on reload"
+}
+
+run new-session -d -x 80 -y 24
+a=$(run display-message -p '#{pane_id}') || exit 1
+b=$(run split-window -dPF '#{pane_id}') || exit 1
+f=$(run new-pane -dPF '#{pane_id}' -x 20 -y 8 -X 8 -Y 3) || exit 1
+run new-window -d
+c=$(run display-message -p -t :1 '#{pane_id}') || exit 1
+d=$(run split-window -dPF '#{pane_id}' -t :1) || exit 1
+
+# a is the top tiled pane, b the bottom one, f is a float and c and d are the
+# tiled panes in window 1.
+check $a 0:0:0:0 start
+check $f 1:0:0:0 start
+check $c 0:0:0:1 start
+checkgeom $a 80x12+0+0 start
+checkgeom $b 80x11+0+13 start
+checkgeom $f 18x6+9+4 start
+
+# Two tiled panes in the same window trade places.
+run swap-pane -d -s $a -t $b
+checkgeom $a 80x11+0+13 'tiled swap'
+checkgeom $b 80x12+0+0 'tiled swap'
+check $a 0:0:0:0 'tiled swap'
+check $b 0:0:0:0 'tiled swap'
+checklayout :0 'tiled swap'
+checkactive :0 $a 'tiled swap keeps active pane'
+run swap-pane -d -s $a -t $b
+checkgeom $a 80x12+0+0 'tiled swap back'
+
+# A tiled pane and a float exchange state as well as place.
+run swap-pane -d -s $b -t $f
+check $b 1:0:0:0 'tiled-float swap'
+check $f 0:0:0:0 'tiled-float swap'
+checkgeom $b 18x6+9+4 'tiled-float swap'
+checkgeom $f 80x11+0+13 'tiled-float swap'
+checklayout :0 'tiled-float swap'
+run swap-pane -d -s $b -t $f
+check $b 0:0:0:0 'tiled-float swap back'
+check $f 1:0:0:0 'tiled-float swap back'
+checkgeom $f 18x6+9+4 'tiled-float swap back'
+
+# The same across windows.
+run swap-pane -d -s $f -t $d
+check $f 0:0:0:1 'float to other window'
+check $d 1:0:0:0 'float to other window'
+checkgeom $f 80x11+0+13 'float to other window'
+checkgeom $d 18x6+9+4 'float to other window'
+checkwin :0 0:3 'float to other window'
+checkwin :1 0:2 'float to other window'
+checklayout :0 'float to other window'
+checklayout :1 'float to other window'
+run swap-pane -d -s $f -t $d
+check $f 1:0:0:0 'float to other window back'
+check $d 0:0:0:1 'float to other window back'
+
+# Zoom stays with the position. Swapping the zoomed pane with an unzoomed one
+# in the same window leaves the position zoomed.
+run resize-pane -Z -t $a
+checkwin :0 1:3 'zoom a'
+run swap-pane -s $a -t $b
+check $a 0:0:0:0 'zoomed-tiled swap'
+check $b 0:1:0:0 'zoomed-tiled swap'
+checkgeom $b 80x24+0+0 'zoomed-tiled swap'
+checkwin :0 1:3 'zoomed-tiled swap'
+run swap-pane -s $b -t $a
+check $a 0:1:0:0 'zoomed-tiled swap back'
+check $b 0:0:0:0 'zoomed-tiled swap back'
+
+# With -d the active pane stays active, unless the swap covers it with the
+# zoomed pane: the zoom must not be hidden, so the pane that took the active
+# pane's place becomes active instead.
+run select-pane -t $a
+run swap-pane -d -s $a -t $b
+check $a 0:0:0:0 'zoomed swap -d'
+check $b 0:1:0:0 'zoomed swap -d'
+checkwin :0 1:3 'zoomed swap -d'
+checkactive :0 $b 'zoomed swap -d'
+run swap-pane -d -s $b -t $a
+check $a 0:1:0:0 'zoomed swap -d back'
+check $b 0:0:0:0 'zoomed swap -d back'
+checkwin :0 1:3 'zoomed swap -d back'
+checkactive :0 $a 'zoomed swap -d back'
+
+# A zoomed tiled pane and a float: the float fills the window, the tiled pane
+# becomes the float.
+run swap-pane -s $a -t $f
+check $a 1:0:0:0 'zoomed-float swap'
+check $f 0:1:0:0 'zoomed-float swap'
+checkgeom $a 18x6+9+4 'zoomed-float swap'
+checkgeom $f 80x24+0+0 'zoomed-float swap'
+checkwin :0 1:3 'zoomed-float swap'
+run swap-pane -s $f -t $a
+check $a 0:1:0:0 'zoomed-float swap back'
+check $f 1:0:0:0 'zoomed-float swap back'
+run resize-pane -Z -t $a
+checkwin :0 0:3 'unzoom a'
+
+# A zoomed float swapped with a tiled pane: the tiled pane becomes the zoomed
+# float.
+run resize-pane -Z -t $f
+check $f 1:1:0:0 'zoom f'
+run swap-pane -s $f -t $b
+check $f 0:0:0:0 'zoomed-float-tiled swap'
+check $b 1:1:0:0 'zoomed-float-tiled swap'
+checkgeom $b 80x24+0+0 'zoomed-float-tiled swap'
+checkwin :0 1:3 'zoomed-float-tiled swap'
+run swap-pane -s $b -t $f
+run resize-pane -Z -t $f
+checkwin :0 0:3 'unzoom f'
+
+# Across windows: a zoomed pane swapped with an unzoomed one. Window 0 stays
+# zoomed with the new pane in the zoomed position and window 1 stays unzoomed.
+run resize-pane -Z -t $a
+run swap-pane -s $a -t $c
+check $a 0:0:0:1 'zoom across windows'
+check $c 0:1:0:0 'zoom across windows'
+checkgeom $c 80x24+0+0 'zoom across windows'
+checkgeom $a 80x12+0+0 'zoom across windows'
+checkwin :0 1:3 'zoom across windows'
+checkwin :1 0:2 'zoom across windows'
+checklayout :0 'zoom across windows'
+checklayout :1 'zoom across windows'
+
+# And back, this time with the unzoomed pane as the source.
+run swap-pane -s $c -t $a
+check $a 0:1:0:0 'zoom across windows back'
+check $c 0:0:0:1 'zoom across windows back'
+checkwin :0 1:3 'zoom across windows back'
+checkwin :1 0:2 'zoom across windows back'
+
+# Both windows zoomed and the zoomed panes swapped: both stay zoomed.
+run resize-pane -Z -t $c
+checkwin :1 1:2 'zoom both'
+run swap-pane -s $a -t $c
+check $a 0:1:0:1 'zoomed both swap'
+check $c 0:1:0:0 'zoomed both swap'
+checkwin :0 1:3 'zoomed both swap'
+checkwin :1 1:2 'zoomed both swap'
+run swap-pane -s $c -t $a
+run resize-pane -Z -t $c
+run resize-pane -Z -t $a
+checkwin :0 0:3 'unzoom all'
+checkwin :1 0:2 'unzoom all'
+
+# A zoomed pane swapped with a covered tiled pane from another window.
+run resize-pane -Z -t $a
+run swap-pane -s $a -t $d
+check $a 0:0:0:1 'zoomed-tiled with other window'
+check $d 0:1:0:0 'zoomed-tiled with other window'
+checkwin :0 1:3 'zoomed-tiled with other window'
+checkwin :1 0:2 'zoomed-tiled with other window'
+run swap-pane -s $d -t $a
+run resize-pane -Z -t $a
+checkwin :0 0:3 'unzoom a again'
+
+# Hidden state also stays with the position.
+run resize-pane -H -t $f
+check $f 1:0:1:0 'hide f'
+run swap-pane -d -s $f -t $b
+check $f 0:0:0:0 'hidden float swap'
+check $b 1:0:1:0 'hidden float swap'
+checkgeom $f 80x11+0+13 'hidden float swap'
+run swap-pane -d -s $f -t $b
+check $f 1:0:1:0 'hidden float swap back'
+check $b 0:0:0:0 'hidden float swap back'
+
+# And across windows.
+run swap-pane -d -s $f -t $d
+check $f 0:0:0:1 'hidden float to other window'
+check $d 1:0:1:0 'hidden float to other window'
+checkwin :0 0:3 'hidden float to other window'
+checkwin :1 0:2 'hidden float to other window'
+run swap-pane -d -s $f -t $d
+run resize-pane -H -t $f
+check $f 1:0:0:0 'show f'
+
+# Without -d the destination becomes active, within and across windows.
+run select-pane -t $a
+run swap-pane -s $a -t $b
+checkactive :0 $b 'swap active'
+run swap-pane -s $a -t $b
+run select-pane -t $c
+run swap-pane -s $a -t $c
+checkactive :0 $c 'swap active across windows'
+checkactive :1 $a 'swap active across windows'
+run swap-pane -s $a -t $c
+run select-window -t :0
+
+# -D and -U wrap around the tiled panes, skipping floats.
+run select-pane -t $a
+run swap-pane -D -d
+checkgeom $a 80x11+0+13 '-D'
+checkgeom $b 80x12+0+0 '-D'
+check $f 1:0:0:0 '-D'
+run swap-pane -U -d
+checkgeom $a 80x12+0+0 '-U'
+checkgeom $b 80x11+0+13 '-U'
+$TMUX swap-pane -D -t $f 2>/dev/null && fail '-D on a float succeeded'
+$TMUX swap-pane -U -t $f 2>/dev/null && fail '-U on a float succeeded'
+
+# With -Z, a window that was zoomed ends up with just the active pane zoomed.
+run resize-pane -Z -t $a
+run resize-pane -Z -t $f
+check $a 0:1:0:0 'two zooms'
+check $f 1:1:0:0 'two zooms'
+run select-pane -t $a
+run swap-pane -Z -s $a -t $b
+check $b 0:1:0:0 '-Z'
+check $f 1:0:0:0 '-Z'
+checkwin :0 1:3 '-Z'
+got=$(run list-panes -t :0 -F '#{pane_zoomed_flag}' | grep -c 1) || exit 1
+[ "$got" = 1 ] || fail "-Z left $got panes zoomed, expected 1"
+run resize-pane -a -Z
+checkwin :0 0:3 'unzoom all'
+
+# A modal pane cannot be swapped.
+m=$(run new-pane -OPF '#{pane_id}' -t $a -x 10 -y 4 -X 2 -Y 2) || exit 1
+$TMUX swap-pane -s $m -t $b 2>/dev/null && fail 'swapped a modal pane'
+$TMUX swap-pane -s $b -t $m 2>/dev/null && fail 'swapped with a modal pane'
+
+exit 0