diff --git a/sys/Makefile.dep b/sys/Makefile.dep
index 67c86388a2..336a58828a 100644
--- a/sys/Makefile.dep
+++ b/sys/Makefile.dep
@@ -213,14 +213,14 @@ ifneq (,$(filter l2util,$(USEMODULE)))
   USEMODULE += fmt
 endif
 
-ifneq (,$(filter od,$(USEMODULE)))
-  USEMODULE += fmt
-endif
-
 ifneq (,$(filter od_string,$(USEMODULE)))
   USEMODULE += od
 endif
 
+ifneq (,$(filter od,$(USEMODULE)))
+  USEMODULE += fmt
+endif
+
 ifneq (,$(filter netutils,$(USEMODULE)))
   USEMODULE += ipv6_addr
 endif
diff --git a/sys/od/Makefile.dep b/sys/od/Makefile.dep
new file mode 100644
index 0000000000..8e78f49e35
--- /dev/null
+++ b/sys/od/Makefile.dep
@@ -0,0 +1 @@
+USEMODULE += fmt