diff --git a/sklearn/linear_model/_ridge.py b/sklearn/linear_model/_ridge.py
index e39af10053c34..2b77e45bf26f7 100644
--- a/sklearn/linear_model/_ridge.py
+++ b/sklearn/linear_model/_ridge.py
@@ -1969,7 +1969,8 @@ def fit(self, X, y, sample_weight=None):
 
         sample_weight : float or ndarray of shape (n_samples,), default=None
             Individual weights for each sample. If given a float, every sample
-            will have the same weight.
+            will have the same weight. The sample_weight vector should sum to
+            one.
 
         Returns
         -------