diff --git a/core/forkid/forkid_test.go b/core/forkid/forkid_test.go
index b33f85bec..304894023 100644
--- a/core/forkid/forkid_test.go
+++ b/core/forkid/forkid_test.go
@@ -72,8 +72,10 @@ func TestCreation(t *testing.T) {
 				{4229999, ID{Hash: checksumToBytes(0x3ea159c7), Next: 4230000}}, // Last Byzantium block
 				{4230000, ID{Hash: checksumToBytes(0x97b544f3), Next: 4939394}}, // First Constantinople block
 				{4939393, ID{Hash: checksumToBytes(0x97b544f3), Next: 4939394}}, // Last Constantinople block
-				{4939394, ID{Hash: checksumToBytes(0xd6e2149b), Next: 0}},       // First Petersburg block
-				{5822692, ID{Hash: checksumToBytes(0xd6e2149b), Next: 0}},       // Today Petersburg block
+				{4939394, ID{Hash: checksumToBytes(0xd6e2149b), Next: 6485846}}, // First Petersburg block
+				{6485845, ID{Hash: checksumToBytes(0xd6e2149b), Next: 6485846}}, // Last Petersburg block
+				{6485846, ID{Hash: checksumToBytes(0x4bc66396), Next: 0}},       // First Istanbul block
+				{7500000, ID{Hash: checksumToBytes(0x4bc66396), Next: 0}},       // Future Istanbul block
 			},
 		},
 		// Rinkeby test cases
@@ -90,8 +92,10 @@ func TestCreation(t *testing.T) {
 				{3660662, ID{Hash: checksumToBytes(0x8d748b57), Next: 3660663}}, // Last Byzantium block
 				{3660663, ID{Hash: checksumToBytes(0xe49cab14), Next: 4321234}}, // First Constantinople block
 				{4321233, ID{Hash: checksumToBytes(0xe49cab14), Next: 4321234}}, // Last Constantinople block
-				{4321234, ID{Hash: checksumToBytes(0xafec6b27), Next: 0}},       // First Petersburg block
-				{4586649, ID{Hash: checksumToBytes(0xafec6b27), Next: 0}},       // Today Petersburg block
+				{4321234, ID{Hash: checksumToBytes(0xafec6b27), Next: 5435345}}, // First Petersburg block
+				{5435344, ID{Hash: checksumToBytes(0xafec6b27), Next: 5435345}}, // Last Petersburg block
+				{5435345, ID{Hash: checksumToBytes(0xcbdb8838), Next: 0}},       // First Istanbul block
+				{6000000, ID{Hash: checksumToBytes(0xcbdb8838), Next: 0}},       // Future Istanbul block
 			},
 		},
 		// Goerli test cases
@@ -99,8 +103,10 @@ func TestCreation(t *testing.T) {
 			params.GoerliChainConfig,
 			params.GoerliGenesisHash,
 			[]testcase{
-				{0, ID{Hash: checksumToBytes(0xa3f5ab08), Next: 0}},      // Unsynced, last Frontier, Homestead, Tangerine, Spurious, Byzantium, Constantinople and first Petersburg block
-				{795329, ID{Hash: checksumToBytes(0xa3f5ab08), Next: 0}}, // Today Petersburg block
+				{0, ID{Hash: checksumToBytes(0xa3f5ab08), Next: 1561651}},       // Unsynced, last Frontier, Homestead, Tangerine, Spurious, Byzantium, Constantinople and first Petersburg block
+				{1561650, ID{Hash: checksumToBytes(0xa3f5ab08), Next: 1561651}}, // Last Petersburg block
+				{1561651, ID{Hash: checksumToBytes(0xc25efa5c), Next: 0}},       // First Istanbul block
+				{2000000, ID{Hash: checksumToBytes(0xc25efa5c), Next: 0}},       // Future Istanbul block
 			},
 		},
 	}
diff --git a/params/config.go b/params/config.go
index 3b2886d53..75facce02 100644
--- a/params/config.go
+++ b/params/config.go
@@ -141,7 +141,7 @@ var (
 		ByzantiumBlock:      big.NewInt(1035301),
 		ConstantinopleBlock: big.NewInt(3660663),
 		PetersburgBlock:     big.NewInt(4321234),
-		IstanbulBlock:       nil,
+		IstanbulBlock:       big.NewInt(5435345),
 		Clique: &CliqueConfig{
 			Period: 15,
 			Epoch:  30000,
@@ -213,16 +213,16 @@ var (
 	//
 	// This configuration is intentionally not using keyed fields to force anyone
 	// adding flags to the config to also have to set these fields.
-	AllEthashProtocolChanges = &ChainConfig{big.NewInt(1337), big.NewInt(0), nil, false, big.NewInt(0), common.Hash{}, big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), nil, nil, new(EthashConfig), nil}
+	AllEthashProtocolChanges = &ChainConfig{big.NewInt(1337), big.NewInt(0), nil, false, big.NewInt(0), common.Hash{}, big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), nil, new(EthashConfig), nil}
 
 	// AllCliqueProtocolChanges contains every protocol change (EIPs) introduced
 	// and accepted by the Ethereum core developers into the Clique consensus.
 	//
 	// This configuration is intentionally not using keyed fields to force anyone
 	// adding flags to the config to also have to set these fields.
-	AllCliqueProtocolChanges = &ChainConfig{big.NewInt(1337), big.NewInt(0), nil, false, big.NewInt(0), common.Hash{}, big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), nil, nil, nil, &CliqueConfig{Period: 0, Epoch: 30000}}
+	AllCliqueProtocolChanges = &ChainConfig{big.NewInt(1337), big.NewInt(0), nil, false, big.NewInt(0), common.Hash{}, big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), nil, nil, &CliqueConfig{Period: 0, Epoch: 30000}}
 
-	TestChainConfig = &ChainConfig{big.NewInt(1), big.NewInt(0), nil, false, big.NewInt(0), common.Hash{}, big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), nil, nil, new(EthashConfig), nil}
+	TestChainConfig = &ChainConfig{big.NewInt(1), big.NewInt(0), nil, false, big.NewInt(0), common.Hash{}, big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), nil, new(EthashConfig), nil}
 	TestRules       = TestChainConfig.Rules(new(big.Int))
 )