diff --git a/lib/runtime-c-api/src/error.rs b/lib/runtime-c-api/src/error.rs
index fda6c77b3..0a578f9e2 100644
--- a/lib/runtime-c-api/src/error.rs
+++ b/lib/runtime-c-api/src/error.rs
@@ -85,7 +85,7 @@ pub unsafe extern "C" fn wasmer_last_error_message(buffer: *mut c_char, length:
     // accidentally read into garbage.
     buffer[error_message.len()] = 0;
 
-    error_message.len() as c_int
+    error_message.len() as c_int + 1
 }
 
 #[derive(Debug)]