diff --git a/Makefile.inc1 b/Makefile.inc1
--- a/Makefile.inc1
+++ b/Makefile.inc1
@@ -2898,7 +2898,7 @@
 		lib/libzstd \
 		${_lib_casper} \
 		lib/ncurses/ncurses \
-		lib/libopie lib/libpam/libpam ${_lib_libthr} \
+		lib/libopie lib/libpam/libpam lib/libthr \
 		${_lib_libradius} lib/libsbuf lib/libtacplus \
 		lib/libgeom \
 		${_cddl_lib_libumem} ${_cddl_lib_libnvpair} \
@@ -2932,10 +2932,6 @@
 lib/libgeom__L: lib/libexpat__L lib/libsbuf__L
 lib/libkvm__L: lib/libelf__L
 
-.if ${MK_LIBTHR} != "no"
-_lib_libthr=	lib/libthr
-.endif
-
 .if ${MK_RADIUS_SUPPORT} != "no"
 _lib_libradius=	lib/libradius
 .endif
diff --git a/cddl/lib/Makefile b/cddl/lib/Makefile
--- a/cddl/lib/Makefile
+++ b/cddl/lib/Makefile
@@ -28,11 +28,9 @@
 _libzfs=	libzfs
 _libzutil=	libzutil
 _libzfsbootenv=	libzfsbootenv
-.if ${MK_LIBTHR} != "no"
 _libzpool=	libzpool
 _libtpool=	libtpool
 .endif
-.endif
 
 SUBDIR_DEPEND_libctf=		libspl
 SUBDIR_DEPEND_libdtrace=	libctf
diff --git a/cddl/usr.bin/Makefile b/cddl/usr.bin/Makefile
--- a/cddl/usr.bin/Makefile
+++ b/cddl/usr.bin/Makefile
@@ -15,12 +15,10 @@
 
 .if ${MK_ZFS} != "no"
 _zinject= zinject
-.if ${MK_LIBTHR} != "no"
 _ztest=	ztest
 _zstream = zstream
 _zstreamdump = zstreamdump
 .endif
-.endif
 
 SUBDIR_PARALLEL=
 
diff --git a/cddl/usr.sbin/Makefile b/cddl/usr.sbin/Makefile
--- a/cddl/usr.sbin/Makefile
+++ b/cddl/usr.sbin/Makefile
@@ -13,10 +13,8 @@
 SUBDIR.${MK_TESTS}+= tests
 
 .if ${MK_ZFS} != "no"
-.if ${MK_LIBTHR} != "no"
 _zdb=	zdb
 _zhack=	zhack
-.endif
 . if ${MK_CXX} != "no"
 _zfsd=	zfsd
 . endif
diff --git a/lib/Makefile b/lib/Makefile
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -93,6 +93,7 @@
 	libstdthreads \
 	libsysdecode \
 	libtacplus \
+	libthr \
 	libthread_db \
 	libucl \
 	libufs \
@@ -137,7 +138,7 @@
 SUBDIR_DEPEND_libtacplus= libmd
 SUBDIR_DEPEND_libulog= libmd
 SUBDIR_DEPEND_libunbound= ${_libldns}
-SUBDIR_DEPEND_liblzma= ${_libthr}
+SUBDIR_DEPEND_liblzma= libthr
 .if ${MK_OFED} != "no"
 SUBDIR_DEPEND_libpcap= ofed
 .endif
@@ -189,7 +190,6 @@
 
 SUBDIR.${MK_EFI}+=	libefivar
 SUBDIR.${MK_GOOGLETEST}+=	googletest
-SUBDIR.${MK_LIBTHR}+=	libthr
 SUBDIR.${MK_NETGRAPH}+=	libnetgraph
 SUBDIR.${MK_NIS}+=	libypclnt
 
diff --git a/sbin/ggate/Makefile b/sbin/ggate/Makefile
--- a/sbin/ggate/Makefile
+++ b/sbin/ggate/Makefile
@@ -2,13 +2,8 @@
 
 .include <src.opts.mk>
 
-SUBDIR=	${_ggatec} \
-	${_ggated} \
+SUBDIR=	ggatec \
+	ggated \
 	ggatel
 
-.if ${MK_LIBTHR} != "no"
-_ggatec=	ggatec
-_ggated=	ggated
-.endif
-
 .include <bsd.subdir.mk>
diff --git a/share/man/man3/Makefile b/share/man/man3/Makefile
--- a/share/man/man3/Makefile
+++ b/share/man/man3/Makefile
@@ -370,7 +370,6 @@
 		tree.3 SPLAY_RIGHT.3 \
 		tree.3 SPLAY_ROOT.3
 
-.if ${MK_LIBTHR} != "no"
 PTHREAD_MAN=	pthread.3 \
 		pthread_affinity_np.3 \
 		pthread_atfork.3 \
@@ -504,6 +503,5 @@
 		pthread_testcancel.3 pthread_setcanceltype.3
 PTHREAD_MLINKS+=pthread_join.3 pthread_peekjoin_np.3 \
 		pthread_join.3 pthread_timedjoin_np.3
-.endif
 
 .include <bsd.prog.mk>
diff --git a/share/mk/src.opts.mk b/share/mk/src.opts.mk
--- a/share/mk/src.opts.mk
+++ b/share/mk/src.opts.mk
@@ -126,8 +126,6 @@
     LDNS_UTILS \
     LEGACY_CONSOLE \
     LIBCPLUSPLUS \
-    LIBPTHREAD \
-    LIBTHR \
     LLD \
     LLD_BOOTSTRAP \
     LLD_IS_LD \
@@ -378,10 +376,6 @@
 MK_CASPER:=	no
 .endif
 
-.if ${MK_LIBPTHREAD} == "no"
-MK_LIBTHR:=	no
-.endif
-
 .if ${MK_SOURCELESS} == "no"
 MK_SOURCELESS_HOST:=	no
 MK_SOURCELESS_UCODE:= no
diff --git a/tools/build/mk/OptionalObsoleteFiles.inc b/tools/build/mk/OptionalObsoleteFiles.inc
--- a/tools/build/mk/OptionalObsoleteFiles.inc
+++ b/tools/build/mk/OptionalObsoleteFiles.inc
@@ -4110,13 +4110,6 @@
 OLD_DIRS+=usr/include/c++/v1
 .endif
 
-.if ${MK_LIBTHR} == no
-OLD_LIBS+=lib/libthr.so.3
-OLD_FILES+=usr/lib/libthr.a
-OLD_FILES+=usr/lib/libthr_p.a
-OLD_FILES+=usr/share/man/man3/libthr.3.gz
-.endif
-
 .if ${MK_LLD} == no
 OLD_FILES+=usr/bin/ld.lld
 .endif
diff --git a/tools/build/options/WITHOUT_LIBPTHREAD b/tools/build/options/WITHOUT_LIBPTHREAD
deleted file mode 100644
--- a/tools/build/options/WITHOUT_LIBPTHREAD
+++ /dev/null
@@ -1,5 +0,0 @@
-.\" $FreeBSD$
-Set to not build the
-.Nm libpthread
-providing library,
-.Nm libthr .
diff --git a/tools/build/options/WITHOUT_LIBTHR b/tools/build/options/WITHOUT_LIBTHR
deleted file mode 100644
--- a/tools/build/options/WITHOUT_LIBTHR
+++ /dev/null
@@ -1,5 +0,0 @@
-.\" $FreeBSD$
-Set to not build the
-.Nm libthr
-(1:1 threading)
-library.
diff --git a/usr.sbin/Makefile b/usr.sbin/Makefile
--- a/usr.sbin/Makefile
+++ b/usr.sbin/Makefile
@@ -162,10 +162,8 @@
 SUBDIR.${MK_LEGACY_CONSOLE}+=	kbdmap
 SUBDIR.${MK_LEGACY_CONSOLE}+=	moused
 SUBDIR.${MK_LEGACY_CONSOLE}+=	vidcontrol
-.if ${MK_LIBTHR} != "no" || ${MK_LIBPTHREAD} != "no"
 SUBDIR.${MK_PPP}+=	pppctl
 SUBDIR.${MK_NS_CACHING}+=	nscd
-.endif
 SUBDIR.${MK_LPR}+=	lpr
 SUBDIR.${MK_MAN_UTILS}+=	manctl
 SUBDIR.${MK_MLX5TOOL}+=	mlx5tool
diff --git a/usr.sbin/ngctl/Makefile b/usr.sbin/ngctl/Makefile
--- a/usr.sbin/ngctl/Makefile
+++ b/usr.sbin/ngctl/Makefile
@@ -11,9 +11,7 @@
 
 LIBADD=	netgraph
 
-.if ${MK_LIBTHR} != "no"
 CFLAGS+= -DEDITLINE
 LIBADD+=	edit pthread
-.endif
 
 .include <bsd.prog.mk>