diff --git a/linopy/model.py b/linopy/model.py
index d5d4830a..871945ba 100644
--- a/linopy/model.py
+++ b/linopy/model.py
@@ -746,7 +746,7 @@ def add_constraints(
         (data,) = xr.broadcast(data, exclude=[TERM_DIM])
 
         if mask is not None:
-            mask = as_dataarray(mask).astype(bool)
+            mask = as_dataarray(mask, coords=data.coords, dims=data.dims).astype(bool)
             mask = broadcast_mask(mask, data.labels)
 
         # Auto-mask based on null expressions or NaN RHS (use numpy for speed)