diff --git a/account/account_test.go b/account/account_test.go
index 1d6a82bb..91097805 100644
--- a/account/account_test.go
+++ b/account/account_test.go
@@ -1067,7 +1067,7 @@ func TestWaitForTransactionReceipt(t *testing.T) {
 	type testSetType struct {
 		Timeout         int
 		Hash            *felt.Felt
-		ExpectedErr     *rpc.RPCError
+		ExpectedErr     error
 		ExpectedReceipt rpc.TransactionReceipt
 	}
 	testSet := map[string][]testSetType{
@@ -1087,10 +1087,7 @@ func TestWaitForTransactionReceipt(t *testing.T) {
 
 		resp, err := acnt.WaitForTransactionReceipt(ctx, test.Hash, 1*time.Second)
 		if test.ExpectedErr != nil {
-			rpcErr, ok := err.(*rpc.RPCError)
-			require.True(t, ok)
-			require.Equal(t, test.ExpectedErr.Code, rpcErr.Code)
-			require.Equal(t, test.ExpectedErr.Message, rpcErr.Message)
+			require.Equal(t, test.ExpectedErr.Error(), err.Error())
 		} else {
 			require.Equal(t, test.ExpectedReceipt.ExecutionStatus, (*resp).ExecutionStatus)
 		}
diff --git a/rpc/call_test.go b/rpc/call_test.go
index b12dabc4..a1823ec2 100644
--- a/rpc/call_test.go
+++ b/rpc/call_test.go
@@ -30,7 +30,7 @@ func TestCall(t *testing.T) {
 		FunctionCall          FunctionCall
 		BlockID               BlockID
 		ExpectedPatternResult *felt.Felt
-		ExpectedError         *RPCError
+		ExpectedError         error
 	}
 	testSet := map[string][]testSetType{
 		"devnet": {
@@ -108,14 +108,10 @@ func TestCall(t *testing.T) {
 	}[testEnv]
 
 	for _, test := range testSet {
-		// TODO: create a test case for the new 'CONTRACT_EXECUTION_ERROR' type"
 		require := require.New(t)
 		output, err := testConfig.provider.Call(context.Background(), FunctionCall(test.FunctionCall), test.BlockID)
 		if test.ExpectedError != nil {
-			rpcErr, ok := err.(*RPCError)
-			require.True(ok)
-			require.Equal(test.ExpectedError.Code, rpcErr.Code)
-			require.Equal(test.ExpectedError.Message, rpcErr.Message)
+			require.EqualError(test.ExpectedError, err.Error())
 		} else {
 			require.NoError(err)
 			require.NotEmpty(output, "should return an output")
diff --git a/rpc/contract_test.go b/rpc/contract_test.go
index 029bfce9..7c0a23c2 100644
--- a/rpc/contract_test.go
+++ b/rpc/contract_test.go
@@ -404,7 +404,7 @@ func TestEstimateMessageFee(t *testing.T) {
 		MsgFromL1
 		BlockID
 		ExpectedFeeEst *FeeEstimation
-		ExpectedError  *RPCError
+		ExpectedError  error
 	}
 
 	// https://sepolia.voyager.online/message/0x273f4e20fc522098a60099e5872ab3deeb7fb8321a03dadbd866ac90b7268361
@@ -470,10 +470,7 @@ func TestEstimateMessageFee(t *testing.T) {
 	for _, test := range testSet {
 		resp, err := testConfig.provider.EstimateMessageFee(context.Background(), test.MsgFromL1, test.BlockID)
 		if err != nil {
-			rpcErr, ok := err.(*RPCError)
-			require.True(t, ok)
-			require.Equal(t, test.ExpectedError.Code, rpcErr.Code)
-			require.Equal(t, test.ExpectedError.Message, rpcErr.Message)
+			require.EqualError(t, test.ExpectedError, err.Error())
 		} else {
 			require.Exactly(t, test.ExpectedFeeEst, resp)
 		}
diff --git a/rpc/errors_test.go b/rpc/errors_test.go
index 86c2411c..e0981d3b 100644
--- a/rpc/errors_test.go
+++ b/rpc/errors_test.go
@@ -8,7 +8,6 @@ import (
 )
 
 func TestRPCError(t *testing.T) {
-	t.Skip("TODO: test the new RPCData field before merge")
 	if testEnv == "mock" {
 		testConfig := beforeEach(t)
 		_, err := testConfig.provider.ChainID(context.Background())
diff --git a/rpc/write_test.go b/rpc/write_test.go
index c56c73b9..005d367f 100644
--- a/rpc/write_test.go
+++ b/rpc/write_test.go
@@ -2,6 +2,7 @@ package rpc
 
 import (
 	"context"
+	"errors"
 	"testing"
 
 	"github.com/NethermindEth/juno/core/felt"
@@ -16,7 +17,7 @@ func TestDeclareTransaction(t *testing.T) {
 	type testSetType struct {
 		DeclareTx     BroadcastDeclareTxnType
 		ExpectedResp  AddDeclareTransactionResponse
-		ExpectedError *RPCError
+		ExpectedError error
 	}
 	testSet := map[string][]testSetType{
 		"devnet":  {},
@@ -39,7 +40,7 @@ func TestDeclareTransaction(t *testing.T) {
 			DeclareTx: BroadcastDeclareTxnV1{},
 			ExpectedResp: AddDeclareTransactionResponse{
 				TransactionHash: utils.TestHexToFelt(t, "0x55b094dc5c84c2042e067824f82da90988674314d37e45cb0032aca33d6e0b9")},
-			ExpectedError: &RPCError{Code: InvalidParams, Message: "Invalid Params"},
+			ExpectedError: errors.New("Invalid Params"),
 		},
 		},
 	}[testEnv]
@@ -47,10 +48,7 @@ func TestDeclareTransaction(t *testing.T) {
 	for _, test := range testSet {
 		resp, err := testConfig.provider.AddDeclareTransaction(context.Background(), test.DeclareTx)
 		if err != nil {
-			rpcErr, ok := err.(*RPCError)
-			require.True(t, ok)
-			require.Equal(t, test.ExpectedError.Code, rpcErr.Code)
-			require.Equal(t, test.ExpectedError.Message, rpcErr.Message)
+			require.Equal(t, test.ExpectedError.Error(), err.Error())
 		} else {
 			require.Equal(t, (*resp.TransactionHash).String(), (*test.ExpectedResp.TransactionHash).String())
 		}