diff --git a/comms/libmodbus/Makefile b/comms/libmodbus/Makefile
index 180c4dddd679..13e4d788e7e3 100644
--- a/comms/libmodbus/Makefile
+++ b/comms/libmodbus/Makefile
@@ -1,35 +1,35 @@
 PORTNAME=	libmodbus
 DISTVERSIONPREFIX=	v
-DISTVERSION=	3.1.8
+DISTVERSION=	3.1.9
 CATEGORIES=	comms
 
 MAINTAINER=	bofh@FreeBSD.org
 COMMENT=	Modbus library
 WWW=		https://libmodbus.org/
 
 LICENSE=	LGPL21+
 LICENSE_FILE=	${WRKSRC}/COPYING.LESSER
 
 USES=		autoreconf cpe gmake libtool pathfix
 USE_GITHUB=	yes
 GH_ACCOUNT=	stephane
 USE_LDCONFIG=	yes
 
 GNU_CONFIGURE=	yes
 
 INSTALL_TARGET=	install-strip
 
 OPTIONS_DEFINE=		DOCS MANPAGES
 OPTIONS_DEFAULT=	MANPAGES
 OPTIONS_SUB=		yes
 
 MANPAGES_BUILD_DEPENDS=	go-md2man:textproc/go-md2man
 
 post-install-MANPAGES-on:
 	go-md2man -in docs/index.md | gzip > ${STAGEDIR}${PREFIX}/share/man/man7/libmodbus.7.gz
 	for files in `${FIND} ${WRKSRC}/docs -type f -name 'modbus*.md'`; do \
 		basefiles=`basename $${files} .md`; \
 		go-md2man -in $${files} | gzip > ${STAGEDIR}${PREFIX}/share/man/man3/$${basefiles}.3.gz; \
 	done
 
 .include <bsd.port.mk>
diff --git a/comms/libmodbus/distinfo b/comms/libmodbus/distinfo
index 3a419fbabbb9..941bc1384a1e 100644
--- a/comms/libmodbus/distinfo
+++ b/comms/libmodbus/distinfo
@@ -1,3 +1,3 @@
-TIMESTAMP = 1751271066
-SHA256 (stephane-libmodbus-v3.1.8_GH0.tar.gz) = 4cabc5dc01b2faab853474c5d9db6386d04f37a476f843e239bff25480310adb
-SIZE (stephane-libmodbus-v3.1.8_GH0.tar.gz) = 201697
+TIMESTAMP = 1751446554
+SHA256 (stephane-libmodbus-v3.1.9_GH0.tar.gz) = 75ac07f49b138a636c65980b92a4792290ee901503c324f2f4e23592bfa036c0
+SIZE (stephane-libmodbus-v3.1.9_GH0.tar.gz) = 204381
diff --git a/comms/libmodbus/pkg-plist b/comms/libmodbus/pkg-plist
index 565ac8cd371c..ed0d32b2ba09 100644
--- a/comms/libmodbus/pkg-plist
+++ b/comms/libmodbus/pkg-plist
@@ -1,77 +1,78 @@
 include/modbus/modbus-rtu.h
 include/modbus/modbus-tcp.h
 include/modbus/modbus-version.h
 include/modbus/modbus.h
 lib/libmodbus.so
 lib/libmodbus.so.5
 lib/libmodbus.so.5.1.0
 libdata/pkgconfig/libmodbus.pc
 %%MANPAGES%%share/man/man3/modbus_close.3.gz
 %%MANPAGES%%share/man/man3/modbus_connect.3.gz
+%%MANPAGES%%share/man/man3/modbus_disable_quirks.3.gz
+%%MANPAGES%%share/man/man3/modbus_enable_quirks.3.gz
 %%MANPAGES%%share/man/man3/modbus_flush.3.gz
 %%MANPAGES%%share/man/man3/modbus_free.3.gz
 %%MANPAGES%%share/man/man3/modbus_get_byte_from_bits.3.gz
 %%MANPAGES%%share/man/man3/modbus_get_byte_timeout.3.gz
 %%MANPAGES%%share/man/man3/modbus_get_float.3.gz
 %%MANPAGES%%share/man/man3/modbus_get_float_abcd.3.gz
 %%MANPAGES%%share/man/man3/modbus_get_float_badc.3.gz
 %%MANPAGES%%share/man/man3/modbus_get_float_cdab.3.gz
 %%MANPAGES%%share/man/man3/modbus_get_float_dcba.3.gz
 %%MANPAGES%%share/man/man3/modbus_get_header_length.3.gz
 %%MANPAGES%%share/man/man3/modbus_get_indication_timeout.3.gz
 %%MANPAGES%%share/man/man3/modbus_get_response_timeout.3.gz
 %%MANPAGES%%share/man/man3/modbus_get_slave.3.gz
 %%MANPAGES%%share/man/man3/modbus_get_socket.3.gz
 %%MANPAGES%%share/man/man3/modbus_mapping_free.3.gz
 %%MANPAGES%%share/man/man3/modbus_mapping_new.3.gz
 %%MANPAGES%%share/man/man3/modbus_mapping_new_start_address.3.gz
 %%MANPAGES%%share/man/man3/modbus_mask_write_register.3.gz
 %%MANPAGES%%share/man/man3/modbus_new_rtu.3.gz
 %%MANPAGES%%share/man/man3/modbus_new_tcp.3.gz
 %%MANPAGES%%share/man/man3/modbus_new_tcp_pi.3.gz
 %%MANPAGES%%share/man/man3/modbus_read_bits.3.gz
 %%MANPAGES%%share/man/man3/modbus_read_input_bits.3.gz
 %%MANPAGES%%share/man/man3/modbus_read_input_registers.3.gz
 %%MANPAGES%%share/man/man3/modbus_read_registers.3.gz
 %%MANPAGES%%share/man/man3/modbus_receive.3.gz
 %%MANPAGES%%share/man/man3/modbus_receive_confirmation.3.gz
 %%MANPAGES%%share/man/man3/modbus_reply.3.gz
 %%MANPAGES%%share/man/man3/modbus_reply_exception.3.gz
 %%MANPAGES%%share/man/man3/modbus_report_slave_id.3.gz
 %%MANPAGES%%share/man/man3/modbus_rtu_get_rts.3.gz
 %%MANPAGES%%share/man/man3/modbus_rtu_get_rts_delay.3.gz
 %%MANPAGES%%share/man/man3/modbus_rtu_get_serial_mode.3.gz
 %%MANPAGES%%share/man/man3/modbus_rtu_set_custom_rts.3.gz
 %%MANPAGES%%share/man/man3/modbus_rtu_set_rts.3.gz
 %%MANPAGES%%share/man/man3/modbus_rtu_set_rts_delay.3.gz
 %%MANPAGES%%share/man/man3/modbus_rtu_set_serial_mode.3.gz
 %%MANPAGES%%share/man/man3/modbus_send_raw_request.3.gz
 %%MANPAGES%%share/man/man3/modbus_set_bits_from_byte.3.gz
 %%MANPAGES%%share/man/man3/modbus_set_bits_from_bytes.3.gz
 %%MANPAGES%%share/man/man3/modbus_set_byte_timeout.3.gz
 %%MANPAGES%%share/man/man3/modbus_set_debug.3.gz
 %%MANPAGES%%share/man/man3/modbus_set_error_recovery.3.gz
 %%MANPAGES%%share/man/man3/modbus_set_float.3.gz
 %%MANPAGES%%share/man/man3/modbus_set_float_abcd.3.gz
 %%MANPAGES%%share/man/man3/modbus_set_float_badc.3.gz
 %%MANPAGES%%share/man/man3/modbus_set_float_cdab.3.gz
 %%MANPAGES%%share/man/man3/modbus_set_float_dcba.3.gz
 %%MANPAGES%%share/man/man3/modbus_set_indication_timeout.3.gz
 %%MANPAGES%%share/man/man3/modbus_set_response_timeout.3.gz
 %%MANPAGES%%share/man/man3/modbus_set_slave.3.gz
 %%MANPAGES%%share/man/man3/modbus_set_socket.3.gz
 %%MANPAGES%%share/man/man3/modbus_strerror.3.gz
 %%MANPAGES%%share/man/man3/modbus_tcp_accept.3.gz
 %%MANPAGES%%share/man/man3/modbus_tcp_listen.3.gz
 %%MANPAGES%%share/man/man3/modbus_tcp_pi_accept.3.gz
 %%MANPAGES%%share/man/man3/modbus_tcp_pi_listen.3.gz
 %%MANPAGES%%share/man/man3/modbus_write_and_read_registers.3.gz
 %%MANPAGES%%share/man/man3/modbus_write_bit.3.gz
 %%MANPAGES%%share/man/man3/modbus_write_bits.3.gz
 %%MANPAGES%%share/man/man3/modbus_write_register.3.gz
 %%MANPAGES%%share/man/man3/modbus_write_registers.3.gz
 %%MANPAGES%%share/man/man7/libmodbus.7.gz
 %%PORTDOCS%%%%DOCSDIR%%/AUTHORS
-%%PORTDOCS%%%%DOCSDIR%%/MIGRATION
 %%PORTDOCS%%%%DOCSDIR%%/NEWS
 %%PORTDOCS%%%%DOCSDIR%%/README.md