diff --git a/source/arm11/cheat.c b/source/arm11/cheat.c
index fc94959..7a4a327 100644
--- a/source/arm11/cheat.c
+++ b/source/arm11/cheat.c
@@ -305,7 +305,7 @@ static int cht_calc_needsize( int mode, int numirq )
         }
     }
 
-    return total + 1;
+    return total + sizeof(instruction_t);
 }
 
 static CodeLocation rom_fit_newsize( CodeLocation rom, int realend, int totalsize, u32 *newsize )