diff --git a/qemu/bin/linux-spice b/qemu/bin/linux-spice
index a2faaf3..e8e1ad3 100755
--- a/qemu/bin/linux-spice
+++ b/qemu/bin/linux-spice
@@ -4,5 +4,5 @@ exec linux \
 	-device virtio-serial \
 	-chardev spicevmc,id=vdagent,debug=0,name=vdagent \
 	-device virtserialport,chardev=vdagent,name=com.redhat.spice.0 \
-	-spice port=5900,addr=127.0.0.1,disable-ticketing=on \
+	-spice port="$(first-free-port 5900)",addr=127.0.0.1,disable-ticketing=on \
 	"$@"
diff --git a/qemu/bin/windows-spice b/qemu/bin/windows-spice
index 6327a9a..da49e67 100755
--- a/qemu/bin/windows-spice
+++ b/qemu/bin/windows-spice
@@ -1,7 +1,7 @@
 #!/bin/sh -x
 exec windows \
 	-vga qxl \
-	-spice port=5900,addr=127.0.0.1,disable-ticketing=on \
+	-spice port="$(first-free-port 5900)",addr=127.0.0.1,disable-ticketing=on \
 	-chardev spicevmc,id=vdagent,name=vdagent \
 	-device virtserialport,chardev=vdagent,name=com.redhat.spice.0 \
 	"$@"