diff --git a/proxyd/proxyd/backend.go b/proxyd/proxyd/backend.go
index f00e951..81ec23c 100644
--- a/proxyd/proxyd/backend.go
+++ b/proxyd/proxyd/backend.go
@@ -30,6 +30,7 @@ import (
 const (
 	JSONRPCVersion       = "2.0"
 	JSONRPCErrorInternal = -32000
+	notFoundRpcError     = -32601
 )
 
 var (
@@ -44,7 +45,7 @@ var (
 		HTTPErrorCode: 500,
 	}
 	ErrMethodNotWhitelisted = &RPCErr{
-		Code:          JSONRPCErrorInternal - 1,
+		Code:          notFoundRpcError,
 		Message:       "rpc method is not whitelisted",
 		HTTPErrorCode: 403,
 	}
diff --git a/proxyd/proxyd/integration_tests/testdata/testdata.txt b/proxyd/proxyd/integration_tests/testdata/testdata.txt
index 14c9124..4bdd635 100644
--- a/proxyd/proxyd/integration_tests/testdata/testdata.txt
+++ b/proxyd/proxyd/integration_tests/testdata/testdata.txt
@@ -2,7 +2,7 @@ name|body|responseBody
 not json|not json|{"jsonrpc":"2.0","error":{"code":-32700,"message":"parse error"},"id":null}
 not json-rpc|{"foo":"bar"}|{"jsonrpc":"2.0","error":{"code":-32600,"message":"invalid JSON-RPC version"},"id":null}
 missing fields json-rpc|{"jsonrpc":"2.0"}|{"jsonrpc":"2.0","error":{"code":-32600,"message":"no method specified"},"id":null}
-bad method json-rpc|{"jsonrpc":"2.0","method":"eth_notSendRawTransaction","id":1}|{"jsonrpc":"2.0","error":{"code":-32001,"message":"rpc method is not whitelisted"},"id":1}
+bad method json-rpc|{"jsonrpc":"2.0","method":"eth_notSendRawTransaction","id":1}|{"jsonrpc":"2.0","error":{"code":-32601,"message":"rpc method is not whitelisted"},"id":1}
 no transaction data|{"jsonrpc":"2.0","method":"eth_sendRawTransaction","params":[],"id":1}|{"jsonrpc":"2.0","error":{"code":-32602,"message":"missing value for required argument 0"},"id":1}
 invalid transaction data|{"jsonrpc":"2.0","method":"eth_sendRawTransaction","params":["0xf6806872fcc650ad4e77e0629206426cd183d751e9ddcc8d5e77"],"id":1}|{"jsonrpc":"2.0","error":{"code":-32602,"message":"rlp: value size exceeds available input length"},"id":1}
 invalid transaction data|{"jsonrpc":"2.0","method":"eth_sendRawTransaction","params":["0x1234"],"id":1}|{"jsonrpc":"2.0","error":{"code":-32602,"message":"transaction type not supported"},"id":1}
@@ -11,4 +11,4 @@ valid transaction data - contract call|{"jsonrpc":"2.0","method":"eth_sendRawTra
 valid chain id - simple send|{"jsonrpc":"2.0","method":"eth_sendRawTransaction","params":["0x02f8748201a415843b9aca31843b9aca3182520894f80267194936da1e98db10bce06f3147d580a62e880de0b6b3a764000080c001a0b50ee053102360ff5fedf0933b912b7e140c90fe57fa07a0cebe70dbd72339dda072974cb7bfe5c3dc54dde110e2b049408ccab8a879949c3b4d42a3a7555a618b"],"id":1}|{"id": 123, "jsonrpc": "2.0", "result": "dummy"}
 invalid chain id - simple send|{"jsonrpc":"2.0","method":"eth_sendRawTransaction","params":["0x02f87683ab41308217af84773594008504a817c80082520894be53e587975603a13d0923d0aa6d37c5233dd750865af3107a400080c001a04ae265f17e882b922d39f0f0cb058a6378df1dc89da8b8165ab6bc53851b426aa0682079486be2aa23bc7514477473362cc7d63afa12c99f7d8fb15e68d69d9a48"],"id":1}|{"jsonrpc":"2.0","error":{"code":-32000,"message":"invalid sender"},"id":1}
 no chain id (pre eip-155) - simple send|{"jsonrpc":"2.0","method":"eth_sendRawTransaction","params":["0xf865808609184e72a00082271094000000000000000000000000000000000000000001001ba0d937ddb66e7788f917864b8e6974cac376b091154db1c25ff8429a6e61016e74a054ced39349e7658b7efceccfabc461e02418eb510124377949cfae8ccf1831af"],"id":1}|{"id": 123, "jsonrpc": "2.0", "result": "dummy"}
-batch with mixed results|[{"jsonrpc":"2.0","method":"eth_sendRawTransaction","params":["0x02f87683ab41308217af84773594008504a817c80082520894be53e587975603a13d0923d0aa6d37c5233dd750865af3107a400080c001a04ae265f17e882b922d39f0f0cb058a6378df1dc89da8b8165ab6bc53851b426aa0682079486be2aa23bc7514477473362cc7d63afa12c99f7d8fb15e68d69d9a48"],"id":1},{"jsonrpc":"2.0","method":"eth_sendRawTransaction","params":["0x02f8748201a415843b9aca31843b9aca3182520894f80267194936da1e98db10bce06f3147d580a62e880de0b6b3a764000080c001a0b50ee053102360ff5fedf0933b912b7e140c90fe57fa07a0cebe70dbd72339dda072974cb7bfe5c3dc54dde110e2b049408ccab8a879949c3b4d42a3a7555a618b"],"id":1},{"bad":"json"},{"jsonrpc":"2.0","method":"eth_fooTheBar","params":[],"id":123}]|[{"jsonrpc":"2.0","error":{"code":-32000,"message":"invalid sender"},"id":1},{"id": 123, "jsonrpc": "2.0", "result": "dummy"},{"jsonrpc":"2.0","error":{"code":-32600,"message":"invalid JSON-RPC version"},"id":null},{"jsonrpc":"2.0","error":{"code":-32001,"message":"rpc method is not whitelisted"},"id":123}]
+batch with mixed results|[{"jsonrpc":"2.0","method":"eth_sendRawTransaction","params":["0x02f87683ab41308217af84773594008504a817c80082520894be53e587975603a13d0923d0aa6d37c5233dd750865af3107a400080c001a04ae265f17e882b922d39f0f0cb058a6378df1dc89da8b8165ab6bc53851b426aa0682079486be2aa23bc7514477473362cc7d63afa12c99f7d8fb15e68d69d9a48"],"id":1},{"jsonrpc":"2.0","method":"eth_sendRawTransaction","params":["0x02f8748201a415843b9aca31843b9aca3182520894f80267194936da1e98db10bce06f3147d580a62e880de0b6b3a764000080c001a0b50ee053102360ff5fedf0933b912b7e140c90fe57fa07a0cebe70dbd72339dda072974cb7bfe5c3dc54dde110e2b049408ccab8a879949c3b4d42a3a7555a618b"],"id":1},{"bad":"json"},{"jsonrpc":"2.0","method":"eth_fooTheBar","params":[],"id":123}]|[{"jsonrpc":"2.0","error":{"code":-32000,"message":"invalid sender"},"id":1},{"id": 123, "jsonrpc": "2.0", "result": "dummy"},{"jsonrpc":"2.0","error":{"code":-32600,"message":"invalid JSON-RPC version"},"id":null},{"jsonrpc":"2.0","error":{"code":-32601,"message":"rpc method is not whitelisted"},"id":123}]
diff --git a/proxyd/proxyd/integration_tests/validation_test.go b/proxyd/proxyd/integration_tests/validation_test.go
index 5f7d5ae..95cfc29 100644
--- a/proxyd/proxyd/integration_tests/validation_test.go
+++ b/proxyd/proxyd/integration_tests/validation_test.go
@@ -11,7 +11,7 @@ import (
 )
 
 const (
-	notWhitelistedResponse        = `{"jsonrpc":"2.0","error":{"code":-32001,"message":"rpc method is not whitelisted custom message"},"id":999}`
+	notWhitelistedResponse        = `{"jsonrpc":"2.0","error":{"code":-32601,"message":"rpc method is not whitelisted custom message"},"id":999}`
 	parseErrResponse              = `{"jsonrpc":"2.0","error":{"code":-32700,"message":"parse error"},"id":null}`
 	invalidJSONRPCVersionResponse = `{"error":{"code":-32600,"message":"invalid JSON-RPC version"},"id":null,"jsonrpc":"2.0"}`
 	invalidIDResponse             = `{"error":{"code":-32600,"message":"invalid ID"},"id":null,"jsonrpc":"2.0"}`
diff --git a/proxyd/proxyd/integration_tests/ws_test.go b/proxyd/proxyd/integration_tests/ws_test.go
index 1548f2a..d52cfab 100644
--- a/proxyd/proxyd/integration_tests/ws_test.go
+++ b/proxyd/proxyd/integration_tests/ws_test.go
@@ -101,7 +101,7 @@ func TestWS(t *testing.T) {
 		{
 			"blacklisted RPC",
 			"}",
-			"{\"jsonrpc\":\"2.0\",\"error\":{\"code\":-32001,\"message\":\"rpc method is not whitelisted\"},\"id\":1}",
+			"{\"jsonrpc\":\"2.0\",\"error\":{\"code\":-32601,\"message\":\"rpc method is not whitelisted\"},\"id\":1}",
 			"{\"id\": 1, \"method\": \"eth_whatever\", \"params\": []}",
 		},
 		{