diff --git a/src/openrct2/CMakeLists.txt b/src/openrct2/CMakeLists.txt
index 367939c962..55882a1097 100644
--- a/src/openrct2/CMakeLists.txt
+++ b/src/openrct2/CMakeLists.txt
@@ -265,3 +265,7 @@ else ()
     # Dummy target to ease invocation
     add_custom_target(${PROJECT_NAME}-headers-check)
 endif ()
+
+if (UNIX)
+    add_definitions(-D_FILE_OFFSET_BITS=64)
+endif ()