diff --git a/lib/instructions/instruction_metrics.c b/lib/instructions/instruction_metrics.c
index 282cf63a5..1d3b0cb4f 100644
--- a/lib/instructions/instruction_metrics.c
+++ b/lib/instructions/instruction_metrics.c
@@ -71,7 +71,7 @@ static struct evmc_instruction_metrics istanbul_metrics[256] = {
     /*                = 0x2e */ {UNDEFINED, 0, 0},
     /*                = 0x2f */ {UNDEFINED, 0, 0},
     /*        ADDRESS = 0x30 */ {BASE, 0, 1},
-    /*        BALANCE = 0x31 */ {400, 1, 1},
+    /*        BALANCE = 0x31 */ {700, 1, 1},
     /*         ORIGIN = 0x32 */ {BASE, 0, 1},
     /*         CALLER = 0x33 */ {BASE, 0, 1},
     /*      CALLVALUE = 0x34 */ {BASE, 0, 1},
@@ -85,7 +85,7 @@ static struct evmc_instruction_metrics istanbul_metrics[256] = {
     /*    EXTCODECOPY = 0x3c */ {700, 4, 0},
     /* RETURNDATASIZE = 0x3d */ {BASE, 0, 1},
     /* RETURNDATACOPY = 0x3e */ {VERYLOW, 3, 0},
-    /*    EXTCODEHASH = 0x3f */ {400, 1, 1},
+    /*    EXTCODEHASH = 0x3f */ {700, 1, 1},
     /*      BLOCKHASH = 0x40 */ {20, 1, 1},
     /*       COINBASE = 0x41 */ {BASE, 0, 1},
     /*      TIMESTAMP = 0x42 */ {BASE, 0, 1},
@@ -106,7 +106,7 @@ static struct evmc_instruction_metrics istanbul_metrics[256] = {
     /*          MLOAD = 0x51 */ {VERYLOW, 1, 1},
     /*         MSTORE = 0x52 */ {VERYLOW, 2, 0},
     /*        MSTORE8 = 0x53 */ {VERYLOW, 2, 0},
-    /*          SLOAD = 0x54 */ {200, 1, 1},
+    /*          SLOAD = 0x54 */ {800, 1, 1},
     /*         SSTORE = 0x55 */ {0, 2, 0},
     /*           JUMP = 0x56 */ {MID, 1, 0},
     /*          JUMPI = 0x57 */ {HIGH, 2, 0},
diff --git a/test/unittests/test_instructions.cpp b/test/unittests/test_instructions.cpp
index 3fe8b4f0e..7414f7724 100644
--- a/test/unittests/test_instructions.cpp
+++ b/test/unittests/test_instructions.cpp
@@ -253,8 +253,11 @@ TEST(instructions, istanbul_hard_fork)
     {
         switch (op)
         {
+        case OP_BALANCE:
+        case OP_EXTCODEHASH:
         case OP_CHAINID:
         case OP_SELFBALANCE:
+        case OP_SLOAD:
             continue;
         default:
             EXPECT_EQ(i[op], p[op]) << op;
@@ -269,4 +272,7 @@ TEST(instructions, istanbul_hard_fork)
     EXPECT_EQ(p[OP_CHAINID].gas_cost, -1);
     EXPECT_EQ(in[OP_CHAINID], std::string{"CHAINID"});
     EXPECT_TRUE(pn[OP_CHAINID] == nullptr);
+    EXPECT_EQ(i[OP_BALANCE].gas_cost, 700);
+    EXPECT_EQ(i[OP_EXTCODEHASH].gas_cost, 700);
+    EXPECT_EQ(i[OP_SLOAD].gas_cost, 800);
 }