diff --git a/scribbu/Makefile.am b/scribbu/Makefile.am
index cdc5220..0dd5bbf 100644
--- a/scribbu/Makefile.am
+++ b/scribbu/Makefile.am
@@ -54,7 +54,7 @@ pkginclude_HEADERS = scribbu.hh		\
 
 AM_YFLAGS = -d
 AM_CPPFLAGS = -I$(srcdir)/.. $(BOOST_CPPFLAGS) $(OPENSSL_INCLUDES) $(GUILE_CFLAGS)
-AM_CXXFLAGS = -std=c++17 -Wno-register $(GUILE_CFLAGS)
+AM_CXXFLAGS = -std=c++20 -Wno-register $(GUILE_CFLAGS)
 AM_LDFLAGS = $(BOOST_LDFLAGS) $(LIBUNISTRING)
 
 libscribbu_la_LIBADD = $(GUILE_LIBS)	 \
diff --git a/src/Makefile.am b/src/Makefile.am
index 66d22d1..4fd19d6 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -6,7 +6,7 @@ scribbu_SOURCES = scribbu.cc command-utilities.hh command-utilities.cc \
 AM_CPPFLAGS = -I$(srcdir)/.. $(BOOST_CPPFLAGS) $(GUILE_CFLAGS) -DDATADIR=\"$(datadir)\" -DSCRIBBU_ALWAYS_DUMP_CORE
 # AM_CPPFLAGS = -I$(srcdir)/.. $(BOOST_CPPFLAGS) $(GUILE_CFLAGS) -DDATADIR=\"$(datadir)\"
 
-AM_CXXFLAGS = -std=c++17 $(GUILE_CFLAGS)
+AM_CXXFLAGS = -std=c++20 $(GUILE_CFLAGS)
 AM_LDFLAGS  = $(BOOST_LDFLAGS) $(LIBUNISTRING)
 scribbu_LDADD = ../scribbu/libscribbu.la \
 	$(GUILE_LIBS)                    \
diff --git a/test/Makefile.am b/test/Makefile.am
index b145bf1..b39e52d 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -44,7 +44,7 @@ unit_SOURCES = unit.cc unit.hh charsets.cc ostream.cc id3v1.cc framesv2.cc \
 	scribbu.cc id3v2-edit.cc tagset.cc winamp-genres.cc
 
 AM_CPPFLAGS = -DBOOST_TEST_DYN_LINK -I$(srcdir)/.. $(BOOST_CPPFLAGS)
-AM_CXXFLAGS = -std=c++17
+AM_CXXFLAGS = -std=c++20
 AM_LDFLAGS  = $(BOOST_LDFLAGS)
 unit_LDADD = ../scribbu/libscribbu.la    \
 	$(GUILE_LIBS)                    \