diff --git a/binarycpython/utils/population_extensions/grid_options_defaults.py b/binarycpython/utils/population_extensions/grid_options_defaults.py
index acb0cc205aa7e66cad0e1aee78d71b7d35868447..776a4a868aa30a5e19bb9cdb12d9d5430846d61c 100644
--- a/binarycpython/utils/population_extensions/grid_options_defaults.py
+++ b/binarycpython/utils/population_extensions/grid_options_defaults.py
@@ -168,6 +168,7 @@ class grid_options_defaults:
             "_total_probability_weighted_mass_run": 0,  # To count the total mass * probability for each system that thread/process has ran
             "modulo": 1,  # run modulo n of the grid.
             "start_at": 0,  # start at the first model
+            "skip_before" : 0, # skip models before this
             ## Grid type evolution
             "_grid_variables": {},  # grid variables
             "gridcode_filename": None,  # filename of gridcode