diff --git a/include/villas/format_type.h b/include/villas/format_type.h
index 68721a9d8..805b930a3 100644
--- a/include/villas/format_type.h
+++ b/include/villas/format_type.h
@@ -97,8 +97,10 @@ struct format_type {
 
 	/** @} */
 
-	size_t size;		/**< Number of bytes to allocate for io::_vd */
-	int flags;		/**< A set of flags which is automatically used. */
+	size_t size;				/**< Number of bytes to allocate for io::_vd */
+	int flags;				/**< A set of flags which is automatically used. */
+	char delimiter;				/**< Newline delimiter. */
+	char separator;				/**< Column separator (used by csv and villas.human formats only) */
 };
 
 struct format_type * format_type_lookup(const char *name);
diff --git a/include/villas/io.h b/include/villas/io.h
index da8fcac3b..d24705a61 100644
--- a/include/villas/io.h
+++ b/include/villas/io.h
@@ -41,6 +41,7 @@ struct io {
 	enum state state;
 	int flags;
 	char delimiter;				/**< Newline delimiter. */
+	char separator;				/**< Column separator (used by csv and villas.human formats only) */
 
 	struct {
 		/** A format type can use this file handle or overwrite the
diff --git a/lib/io.c b/lib/io.c
index 7461e8643..689a46e6d 100644
--- a/lib/io.c
+++ b/lib/io.c
@@ -89,7 +89,8 @@ int io_init(struct io *io, struct format_type *fmt, struct node *n, int flags)
 	io->_vd = alloc(fmt->size);
 
 	io->flags = flags | io->_vt->flags;
-	io->delimiter = '\n';
+	io->delimiter = io->_vt->delimiter ? io->_vt->delimiter : '\n';
+	io->separator = io->_vt->separator ? io->_vt->separator : '\t';
 
 	io->input.buflen =
 	io->output.buflen = 4096;