diff --git a/.travis.yml b/.travis.yml
index aa3c5ced23..d7b8580d8c 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -24,7 +24,7 @@ install:
   #   /home/travis/gopath/src/github.com/harmony-one/harmony
   # https://docs.travis-ci.com/user/languages/go/#go-import-path
   - echo $TRAVIS_PULL_REQUEST_BRANCH
-  - TEST_REPO_BRANCH="master"
+  - TEST_REPO_BRANCH="feature/effective-gas-price"
   - git clone https://github.com/harmony-one/mcl.git $GOPATH/src/github.com/harmony-one/mcl
   - git clone https://github.com/harmony-one/bls.git $GOPATH/src/github.com/harmony-one/bls
   - git clone --branch $TEST_REPO_BRANCH https://github.com/harmony-one/harmony-test.git $GOPATH/src/github.com/harmony-one/harmony-test
diff --git a/core/state_processor.go b/core/state_processor.go
index fb7290c077..9601357813 100644
--- a/core/state_processor.go
+++ b/core/state_processor.go
@@ -334,6 +334,7 @@ func ApplyTransaction(bc ChainContext, author *common.Address, gp *GasPool, stat
 	receipt := types.NewReceipt(root, failedExe, *usedGas)
 	receipt.TxHash = tx.Hash()
 	receipt.GasUsed = result.UsedGas
+	receipt.EffectiveGasPrice = tx.EffectiveGasPrice(big.NewInt(0), nil)
 	// if the transaction created a contract, store the creation address in the receipt.
 	if msg.To() == nil {
 		receipt.ContractAddress = crypto.CreateAddress(vmenv.Context.Origin, tx.Nonce())
diff --git a/core/types/receipt.go b/core/types/receipt.go
index d0a6c6dc76..6207332d4e 100644
--- a/core/types/receipt.go
+++ b/core/types/receipt.go
@@ -20,6 +20,7 @@ import (
 	"bytes"
 	"fmt"
 	"io"
+	"math/big"
 	"unsafe"
 
 	"github.com/ethereum/go-ethereum/common"
@@ -54,9 +55,10 @@ type Receipt struct {
 	Logs              []*Log         `json:"logs"              gencodec:"required"`
 
 	// Implementation fields (don't reorder!)
-	TxHash          common.Hash    `json:"transactionHash" gencodec:"required"`
-	ContractAddress common.Address `json:"contractAddress"`
-	GasUsed         uint64         `json:"gasUsed" gencodec:"required"`
+	TxHash            common.Hash    `json:"transactionHash" gencodec:"required"`
+	ContractAddress   common.Address `json:"contractAddress"`
+	GasUsed           uint64         `json:"gasUsed" gencodec:"required"`
+	EffectiveGasPrice *big.Int       `json:"effectiveGasPrice"` // required, but tag omitted for backwards compatibility
 }
 
 type receiptMarshaling struct {
@@ -82,6 +84,7 @@ type receiptStorageRLP struct {
 	ContractAddress   common.Address
 	Logs              []*LogForStorage
 	GasUsed           uint64
+	EffectiveGasPrice *big.Int `rlp:"optional"`
 }
 
 // NewReceipt creates a barebone transaction receipt, copying the init fields.
@@ -166,6 +169,7 @@ func (r *ReceiptForStorage) EncodeRLP(w io.Writer) error {
 		ContractAddress:   r.ContractAddress,
 		Logs:              make([]*LogForStorage, len(r.Logs)),
 		GasUsed:           r.GasUsed,
+		EffectiveGasPrice: r.EffectiveGasPrice,
 	}
 	for i, log := range r.Logs {
 		enc.Logs[i] = (*LogForStorage)(log)
@@ -191,6 +195,7 @@ func (r *ReceiptForStorage) DecodeRLP(s *rlp.Stream) error {
 	}
 	// Assign the implementation fields
 	r.TxHash, r.ContractAddress, r.GasUsed = dec.TxHash, dec.ContractAddress, dec.GasUsed
+	r.EffectiveGasPrice = dec.EffectiveGasPrice
 	return nil
 }
 
diff --git a/core/types/receipt_test.go b/core/types/receipt_test.go
index 5a8891cf44..514546e032 100644
--- a/core/types/receipt_test.go
+++ b/core/types/receipt_test.go
@@ -1,13 +1,15 @@
 package types
 
 import (
+	"math/big"
 	"reflect"
 	"testing"
 
 	ethcommon "github.com/ethereum/go-ethereum/common"
-
 	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/ethereum/go-ethereum/rlp"
 	"github.com/harmony-one/harmony/staking"
+	"github.com/stretchr/testify/require"
 )
 
 func TestFindLogsWithTopic(t *testing.T) {
@@ -112,3 +114,67 @@ func TestFindLogsWithTopic(t *testing.T) {
 		}
 	}
 }
+
+// Test we can still parse receipt without EffectiveGasPrice for backwards compatibility, even
+// though it is required per the spec.
+func TestEffectiveGasPriceNotRequired(t *testing.T) {
+	r := &Receipt{
+		Status:            ReceiptStatusFailed,
+		CumulativeGasUsed: 1,
+		Logs:              []*Log{},
+		// derived fields:
+		TxHash:          ethcommon.BytesToHash([]byte{0x03, 0x14}),
+		ContractAddress: ethcommon.HexToAddress("0x5a443704dd4b594b382c22a083e2bd3090a6fef3"),
+		GasUsed:         1,
+	}
+
+	r.EffectiveGasPrice = nil
+	b, err := r.MarshalJSON()
+	if err != nil {
+		t.Fatal("error marshaling receipt to json:", err)
+	}
+	r2 := Receipt{}
+	err = r2.UnmarshalJSON(b)
+	if err != nil {
+		t.Fatal("error unmarshalling receipt from json:", err)
+	}
+}
+
+func TestReceiptEncDec(t *testing.T) {
+	r := ReceiptForStorage(Receipt{
+		Status:            ReceiptStatusFailed,
+		CumulativeGasUsed: 1,
+		Logs:              []*Log{},
+		// derived fields:
+		TxHash:            ethcommon.BytesToHash([]byte{0x03, 0x14}),
+		ContractAddress:   ethcommon.HexToAddress("0x5a443704dd4b594b382c22a083e2bd3090a6fef3"),
+		GasUsed:           1,
+		EffectiveGasPrice: big.NewInt(1),
+	})
+
+	bytes, err := rlp.EncodeToBytes(&r)
+	if err != nil {
+		t.Fatal("error encoding receipt to bytes:", err)
+	}
+
+	r2 := ReceiptForStorage{}
+	err = rlp.DecodeBytes(bytes, &r2)
+	if err != nil {
+		t.Fatal("error decoding receipt from bytes:", err)
+	}
+
+	require.Equal(t, r, r2)
+}
+
+func TestReceiptDecodeEmptyEffectiveGasPrice(t *testing.T) {
+	r := ReceiptForStorage(Receipt{})
+
+	bytes, err := rlp.EncodeToBytes(&r)
+	require.NoError(t, err, "error encoding receipt to bytes")
+
+	r2 := ReceiptForStorage{}
+	err = rlp.DecodeBytes(bytes, &r2)
+	require.NoError(t, err, "error decoding receipt from bytes")
+
+	require.EqualValues(t, r.EffectiveGasPrice, r2.EffectiveGasPrice)
+}
diff --git a/core/types/transaction.go b/core/types/transaction.go
index bee69a393f..590c99b8b8 100644
--- a/core/types/transaction.go
+++ b/core/types/transaction.go
@@ -178,6 +178,10 @@ func (d *txdata) CopyFrom(d2 *txdata) {
 	d.Hash = copyHash(d2.Hash)
 }
 
+func (d *txdata) effectiveGasPrice(dst *big.Int, baseFee *big.Int) *big.Int {
+	return dst.Set(d.Price)
+}
+
 type txdataMarshaling struct {
 	AccountNonce hexutil.Uint64
 	Price        *hexutil.Big
@@ -532,6 +536,11 @@ func (tx *Transaction) SenderAddress() (common.Address, error) {
 	return addr, nil
 }
 
+// EffectiveGasPrice returns the effective gas price of the transaction.
+func (tx *Transaction) EffectiveGasPrice(dst *big.Int, baseFee *big.Int) *big.Int {
+	return tx.data.effectiveGasPrice(dst, baseFee)
+}
+
 // TxByNonce implements the sort interface to allow sorting a list of transactions
 // by their nonces. This is usually only useful for sorting transactions from a
 // single account, otherwise a nonce comparison doesn't make much sense.
diff --git a/rpc/harmony/eth/types.go b/rpc/harmony/eth/types.go
index a319a8fc12..120129f45d 100644
--- a/rpc/harmony/eth/types.go
+++ b/rpc/harmony/eth/types.go
@@ -152,6 +152,7 @@ func NewReceipt(senderAddr common.Address, tx *types.EthTransaction, blockHash c
 		"contractAddress":   nil,
 		"logs":              receipt.Logs,
 		"logsBloom":         receipt.Bloom,
+		"effectiveGasPrice": hexutil.Big(*receipt.EffectiveGasPrice),
 	}
 
 	// Assign receipt status or post state.
diff --git a/rpc/harmony/v1/types.go b/rpc/harmony/v1/types.go
index c297cfbe7e..0a8e02acfb 100644
--- a/rpc/harmony/v1/types.go
+++ b/rpc/harmony/v1/types.go
@@ -188,6 +188,7 @@ type TxReceipt struct {
 	To                string         `json:"to"`
 	Root              hexutil.Bytes  `json:"root"`
 	Status            hexutil.Uint   `json:"status"`
+	EffectiveGasPrice hexutil.Big    `json:"effectiveGasPrice"`
 }
 
 // StakingTxReceipt represents a staking transaction receipt that will serialize to the RPC representation.
@@ -359,6 +360,7 @@ func NewTxReceipt(
 		To:                receiver,
 		Root:              receipt.PostState,
 		Status:            hexutil.Uint(receipt.Status),
+		EffectiveGasPrice: hexutil.Big(*receipt.EffectiveGasPrice),
 	}
 
 	// Set empty array for empty logs
diff --git a/rpc/harmony/v2/types.go b/rpc/harmony/v2/types.go
index c9abbead05..003a690861 100644
--- a/rpc/harmony/v2/types.go
+++ b/rpc/harmony/v2/types.go
@@ -218,6 +218,7 @@ type TxReceipt struct {
 	To                string         `json:"to"`
 	Root              hexutil.Bytes  `json:"root"`
 	Status            uint           `json:"status"`
+	EffectiveGasPrice hexutil.Big    `json:"effectiveGasPrice"`
 }
 
 // StakingTxReceipt represents a staking transaction receipt that will serialize to the RPC representation.
@@ -388,6 +389,7 @@ func NewTxReceipt(
 		To:                receiver,
 		Root:              receipt.PostState,
 		Status:            uint(receipt.Status),
+		EffectiveGasPrice: hexutil.Big(*receipt.EffectiveGasPrice),
 	}
 
 	// Set optionals