diff --git a/singer_sdk/streams/rest.py b/singer_sdk/streams/rest.py
index c65ee3f56..956f61f46 100644
--- a/singer_sdk/streams/rest.py
+++ b/singer_sdk/streams/rest.py
@@ -107,7 +107,7 @@ def __init__(
         super().__init__(name=name, schema=schema, tap=tap)
         if path:
             self.path = path
-        self._http_headers: dict = {}
+        self._http_headers: dict = {"User-Agent": self.user_agent}
         self._requests_session = requests.Session()
         self._compiled_jsonpath = None
         self._next_page_token_compiled_jsonpath = None
@@ -157,6 +157,15 @@ def requests_session(self) -> requests.Session:
             self._requests_session = requests.Session()
         return self._requests_session
 
+    @property
+    def user_agent(self) -> str:
+        """Get the user agent string for the stream.
+
+        Returns:
+            The user agent string.
+        """
+        return f"{self.tap_name}/{self._tap.plugin_version}"
+
     def validate_response(self, response: requests.Response) -> None:
         """Validate HTTP response.
 
@@ -560,10 +569,7 @@ def http_headers(self) -> dict:
         Returns:
             Dictionary of HTTP headers to use as a base for every request.
         """
-        result = self._http_headers
-        if "user_agent" in self.config:
-            result["User-Agent"] = self.config.get("user_agent")
-        return result
+        return self._http_headers
 
     @property
     def timeout(self) -> int: