diff --git a/changelog.d/1584 b/changelog.d/1584
new file mode 100644
index 000000000..8ecba5890
--- /dev/null
+++ b/changelog.d/1584
@@ -0,0 +1,10 @@
+synopsis:  Escape special chars in QueryParams.
+prs: #1597
+issues: #1584
+
+description: {
+
+Escape special chars in QueryParam (':@&=+$') in servant-client. Note that this
+mean binary data will not work as is, and so reverts the functionality in #1432.
+
+}
diff --git a/servant-client/test/Servant/SuccessSpec.hs b/servant-client/test/Servant/SuccessSpec.hs
index d0866084e..3edfc4218 100644
--- a/servant-client/test/Servant/SuccessSpec.hs
+++ b/servant-client/test/Servant/SuccessSpec.hs
@@ -101,11 +101,6 @@ successSpec = beforeAll (startWaiApp server) $ afterAll endWaiApp $ do
       Left (FailureResponse _ r) <- runClient (getQueryParam (Just "bob")) baseUrl
       responseStatusCode r `shouldBe` HTTP.Status 400 "bob not found"
 
-    it "Servant.API.QueryParam binary data" $ \(_, baseUrl) -> do
-      let payload = BS.pack [0, 1, 2, 4, 8, 16, 32, 64, 128]
-          apiCall = getQueryParamBinary (Just $ UrlEncodedByteString payload) HTTP.methodGet
-      (show +++ responseBody) <$> runClient apiCall baseUrl `shouldReturn` Right (BL.fromStrict payload)
-
     it "Servant.API.QueryParam.QueryParams" $ \(_, baseUrl) -> do
       left show <$> runClient (getQueryParams []) baseUrl `shouldReturn` Right []
       left show <$> runClient (getQueryParams ["alice", "bob"]) baseUrl