diff --git a/fastapi/encoders.py b/fastapi/encoders.py
index c5fce04c8..903076ebc 100644
--- a/fastapi/encoders.py
+++ b/fastapi/encoders.py
@@ -394,7 +394,7 @@ def find_encoder(
     # fastpath for exact class match
     encoder = encoders.get(type(value))
     if encoder:
-        return encoder(value)
+        return encoder
 
     # fallback to isinstance which uses MRO
     for encoder_type, encoder in encoders.items():