diff --git a/scripts/build_population_layouts.py b/scripts/build_population_layouts.py
index aa520eba..997e1e5a 100644
--- a/scripts/build_population_layouts.py
+++ b/scripts/build_population_layouts.py
@@ -41,7 +41,7 @@ if __name__ == "__main__":
     # but imprecisions mean not perfect
     Iinv = cutout.indicatormatrix(nuts3.geometry)
 
-    countries = snakemake.config["countries"]
+    countries = np.sort(snakemake.config["countries"])
 
     urban_fraction = (
         pd.read_csv(