diff --git a/sdk/client/test/config.go b/sdk/client/test/config.go
index af023ef6f..b897e1a97 100644
--- a/sdk/client/test/config.go
+++ b/sdk/client/test/config.go
@@ -1,7 +1,7 @@
 package test
 
 const (
-	TEST_PRIVATE_KEY = "3018f5ceec22c2a1389fe3a0933b52f3fc31450c5322002dd76477964797fb13"
+	TEST_PRIVATE_KEY = "ff0911d998e6f12cf4b0a88d90cc411aa3be06c9dc5a2b35834f0e25a44e2275"
 	TEST_ADDR        = "0x76d244CE05c3De4BbC6fDd7F56379B145709ade9"
 	TEST_ADDR2       = "0x5dEfC28ce1Ed331D56aB6F607f78708880e11Bea"
 	TEST_ADDR3       = "0x593107F1D5D10A68D3C3722C35ADa2eb779D44A4"
@@ -10,5 +10,5 @@ const (
 	TEST_GRPC_ADDR   = "localhost:9090"
 	TEST_RPC_ADDR    = "http://0.0.0.0:26750"
 	TEST_CHAIN_ID    = "greenfield_9000-121"
-	TEST_TOKEN_NAME  = "bnb"
+	TEST_TOKEN_NAME  = "BNB"
 )
diff --git a/sdk/client/tx.go b/sdk/client/tx.go
index fd3a356be..5eb1d1cf6 100644
--- a/sdk/client/tx.go
+++ b/sdk/client/tx.go
@@ -16,8 +16,6 @@ import (
 	"github.com/bnb-chain/greenfield/sdk/types"
 )
 
-const GasMultiplier = float64(1.2)
-
 type TransactionClient interface {
 	BroadcastTx(msgs []sdk.Msg, txOpt *types.TxOption, opts ...grpc.CallOption) (*tx.BroadcastTxResponse, error)
 	SimulateTx(msgs []sdk.Msg, txOpt *types.TxOption, opts ...grpc.CallOption) (*tx.SimulateResponse, error)
@@ -31,7 +29,7 @@ func (c *GreenfieldClient) BroadcastTx(msgs []sdk.Msg, txOpt *types.TxOption, op
 	txBuilder := txConfig.NewTxBuilder()
 
 	// txBuilder holds tx info
-	if err := c.constructTxWithGasLimit(msgs, txOpt, txConfig, txBuilder); err != nil {
+	if err := c.constructTxWithGasInfo(msgs, txOpt, txConfig, txBuilder); err != nil {
 		return nil, err
 	}
 
@@ -96,7 +94,7 @@ func (c *GreenfieldClient) simulateTx(txBytes []byte, opts ...grpc.CallOption) (
 func (c *GreenfieldClient) SignTx(msgs []sdk.Msg, txOpt *types.TxOption) ([]byte, error) {
 	txConfig := authtx.NewTxConfig(c.codec, []signing.SignMode{signing.SignMode_SIGN_MODE_EIP_712})
 	txBuilder := txConfig.NewTxBuilder()
-	if err := c.constructTxWithGasLimit(msgs, txOpt, txConfig, txBuilder); err != nil {
+	if err := c.constructTxWithGasInfo(msgs, txOpt, txConfig, txBuilder); err != nil {
 		return nil, err
 	}
 	return c.signTx(txConfig, txBuilder)
@@ -174,9 +172,6 @@ func (c *GreenfieldClient) constructTx(msgs []sdk.Msg, txOpt *types.TxOption, tx
 		if txOpt.Memo != "" {
 			txBuilder.SetMemo(txOpt.Memo)
 		}
-		if !txOpt.FeeAmount.IsZero() {
-			txBuilder.SetFeeAmount(txOpt.FeeAmount)
-		}
 		if !txOpt.FeePayer.Empty() {
 			txBuilder.SetFeePayer(txOpt.FeePayer)
 		}
@@ -185,17 +180,11 @@ func (c *GreenfieldClient) constructTx(msgs []sdk.Msg, txOpt *types.TxOption, tx
 	return c.setSingerInfo(txBuilder)
 }
 
-func (c *GreenfieldClient) constructTxWithGasLimit(msgs []sdk.Msg, txOpt *types.TxOption, txConfig client.TxConfig, txBuilder client.TxBuilder) error {
-	// construct a tx with txOpt excluding GasLimit
-	err := c.constructTx(msgs, txOpt, txBuilder)
-	if err != nil {
+func (c *GreenfieldClient) constructTxWithGasInfo(msgs []sdk.Msg, txOpt *types.TxOption, txConfig client.TxConfig, txBuilder client.TxBuilder) error {
+	// construct a tx with txOpt excluding GasLimit and
+	if err := c.constructTx(msgs, txOpt, txBuilder); err != nil {
 		return err
 	}
-	if txOpt != nil && txOpt.GasLimit != 0 {
-		txBuilder.SetGasLimit(txOpt.GasLimit)
-		return nil
-	}
-
 	txBytes, err := txConfig.TxEncoder()(txBuilder.GetTx())
 	if err != nil {
 		return err
@@ -204,7 +193,26 @@ func (c *GreenfieldClient) constructTxWithGasLimit(msgs []sdk.Msg, txOpt *types.
 	if err != nil {
 		return err
 	}
-	txBuilder.SetGasLimit(uint64(GasMultiplier * float64(simulateRes.GasInfo.GetGasUsed())))
+
+	gasLimit := simulateRes.GasInfo.GetGasUsed()
+	if txOpt != nil && txOpt.GasLimit != 0 {
+		gasLimit = txOpt.GasLimit
+	}
+	gasPrice, err := sdk.ParseCoinsNormalized(simulateRes.GasInfo.GetMinGasPrices())
+	if err != nil {
+		return err
+	}
+	if gasPrice.IsZero() {
+		return types.SimulatedGasPriceError
+	}
+	feeAmount := sdk.NewCoins(sdk.NewInt64Coin(types.Denom,
+		sdk.NewInt(int64(gasLimit)).Mul(gasPrice[0].Amount).Int64()),
+	)
+	if txOpt != nil && !txOpt.FeeAmount.IsZero() {
+		feeAmount = txOpt.FeeAmount
+	}
+	txBuilder.SetGasLimit(gasLimit)
+	txBuilder.SetFeeAmount(feeAmount)
 	return nil
 }
 
diff --git a/sdk/client/tx_test.go b/sdk/client/tx_test.go
index 23fdf0907..5cbe9adf7 100644
--- a/sdk/client/tx_test.go
+++ b/sdk/client/tx_test.go
@@ -43,11 +43,10 @@ func TestSendTokenWithTxOptionSucceed(t *testing.T) {
 	assert.NoError(t, err)
 	mode := tx.BroadcastMode_BROADCAST_MODE_BLOCK
 	txOpt := &types.TxOption{
-		Mode:      &mode,
-		GasLimit:  123456,
-		Memo:      "test",
-		FeeAmount: sdk.NewCoins(sdk.NewInt64Coin(test.TEST_TOKEN_NAME, 1)),
-		FeePayer:  payerAddr,
+		Mode:     &mode,
+		GasLimit: 123456,
+		Memo:     "test",
+		FeePayer: payerAddr,
 	}
 	response, err := gnfdCli.BroadcastTx([]sdk.Msg{transfer}, txOpt)
 	assert.NoError(t, err)
diff --git a/sdk/types/errors.go b/sdk/types/errors.go
index 11cf1822e..e50a14fd5 100644
--- a/sdk/types/errors.go
+++ b/sdk/types/errors.go
@@ -7,4 +7,5 @@ import (
 var (
 	KeyManagerNotInitError = errors.New("Key manager is not initialized yet ")
 	ChainIdNotSetError     = errors.New("ChainID is not set yet ")
+	SimulatedGasPriceError = errors.New("Simulated gas price is 0 ")
 )
diff --git a/sdk/types/type.go b/sdk/types/type.go
index e0b977722..38f216f38 100644
--- a/sdk/types/type.go
+++ b/sdk/types/type.go
@@ -5,6 +5,8 @@ import (
 	"github.com/cosmos/cosmos-sdk/types/tx"
 )
 
+const Denom = "BNB"
+
 type TxOption struct {
 	Mode      *tx.BroadcastMode
 	GasLimit  uint64