diff --git a/getstream/base.py b/getstream/base.py
index 4dbd48e1..94a2f5d5 100644
--- a/getstream/base.py
+++ b/getstream/base.py
@@ -152,9 +152,10 @@ def _strip_none(obj):
 def build_path(path: str, path_params: Optional[Dict[str, Any]]) -> str:
     if path_params is None:
         return path
-    for k, v in path_params.items():
-        path_params[k] = quote(str(v), safe="")
-    return path.format(**path_params)
+    # Quote into a new dict: the caller's mapping is reused when a request is
+    # retried, so mutating it would percent-encode the values twice.
+    quoted = {k: quote(str(v), safe="") for k, v in path_params.items()}
+    return path.format(**quoted)
 
 
 class ResponseParserMixin:
diff --git a/tests/test_retry.py b/tests/test_retry.py
index 601ebea0..24015563 100644
--- a/tests/test_retry.py
+++ b/tests/test_retry.py
@@ -459,3 +459,49 @@ async def capture_sleep(seconds):
     assert counter.calls == 2
     assert slept == [1.0]  # clamped from 5s to max_backoff=1.0
     await client.aclose()
+
+
+# ── path parameters ─────────────────────────────────────────────────
+
+
+class PathRecorder(Counter):
+    def __init__(self, responses):
+        super().__init__(responses)
+        self.raw_paths = []
+
+    def __call__(self, request: httpx.Request) -> httpx.Response:
+        self.raw_paths.append(request.url.raw_path.decode().split("?")[0])
+        return super().__call__(request)
+
+
+def test_retry_does_not_re_encode_path_params(monkeypatch):
+    """A retried GET sends the same URL path as the first attempt."""
+    counter = PathRecorder(
+        [
+            httpx.Response(429, json=rate_limited_body()),
+            httpx.Response(200, json={}),
+        ]
+    )
+    client = sync_client(counter, retry=ENABLED, monkeypatch=monkeypatch)
+    client.get("/api/v2/things/{thing_id}", path_params={"thing_id": "a b:c"})
+    assert counter.raw_paths == [
+        "/api/v2/things/a%20b%3Ac",
+        "/api/v2/things/a%20b%3Ac",
+    ]
+
+
+@pytest.mark.asyncio
+async def test_async_retry_does_not_re_encode_path_params(monkeypatch):
+    counter = PathRecorder(
+        [
+            httpx.Response(429, json=rate_limited_body()),
+            httpx.Response(200, json={}),
+        ]
+    )
+    client = async_client(counter, retry=ENABLED, monkeypatch=monkeypatch)
+    await client.get("/api/v2/things/{thing_id}", path_params={"thing_id": "a b:c"})
+    assert counter.raw_paths == [
+        "/api/v2/things/a%20b%3Ac",
+        "/api/v2/things/a%20b%3Ac",
+    ]
+    await client.aclose()