diff --git a/alpaca/data/models/bars.py b/alpaca/data/models/bars.py
index 76d67b92..cf8f1806 100644
--- a/alpaca/data/models/bars.py
+++ b/alpaca/data/models/bars.py
@@ -12,7 +12,7 @@ class Bar(BaseModel):
 
     Attributes:
         symbol (str): The ticker identifier for the security whose data forms the bar.
-        timestamp (datetime): The closing timestamp of the bar.
+        timestamp (datetime): The opening timestamp of the bar.
         open (float): The opening price of the interval.
         high (float): The high price during the interval.
         low (float): The low price during the interval.