diff --git a/Makefile.inc1 b/Makefile.inc1
--- a/Makefile.inc1
+++ b/Makefile.inc1
@@ -1847,7 +1847,11 @@
 .else
 # First kernel is installed separately by INSTALLKERNEL, typically to
 # /boot/kernel, rather than to a config-suffixed directory.
+.if ${BUILDKERNELS:[#]} > 1
 INSTALLEXTRAKERNELS=	${BUILDKERNELS:[2..-1]}
+.else
+INSTALLEXTRAKERNELS=
+.endif
 .endif
 .endif