diff --git a/converted-ethereum-tests.txt b/converted-ethereum-tests.txt
index 8d1cc2907ca..9da29b98290 100644
--- a/converted-ethereum-tests.txt
+++ b/converted-ethereum-tests.txt
@@ -1,3 +1,7 @@
+([#1236](https://github.com/ethereum/execution-spec-tests/pull/1236))
+GeneralStateTests/VMTests/vmTests/calldataload.json
+GeneralStateTests/VMTests/vmTests/calldatasize.json
+
 ([#1056](https://github.com/ethereum/execution-spec-tests/pull/1056))
 GeneralStateTests/VMTests/vmTests/calldatacopy.json
 
diff --git a/docs/CHANGELOG.md b/docs/CHANGELOG.md
index 6635f5c8b71..373f53e5d5c 100644
--- a/docs/CHANGELOG.md
+++ b/docs/CHANGELOG.md
@@ -68,6 +68,7 @@ consume cache --help
 - ✨ Add EIP-7702 incorrect-rlp-encoding tests ([#1347](https://github.com/ethereum/execution-spec-tests/pull/1347)).
 - ✨ Add EIP-2935 tests for all call opcodes ([#1379](https://github.com/ethereum/execution-spec-tests/pull/1379)).
 - ✨ Add more tests for EIP-7702: max-fee-per-gas verification, delegation-designation as initcode tests ([#1372](https://github.com/ethereum/execution-spec-tests/pull/1372)).
+- ✨ Port [calldataload](https://github.com/ethereum/tests/blob/ae4791077e8fcf716136e70fe8392f1a1f1495fb/src/GeneralStateTestsFiller/VMTests/vmTests/calldatacopyFiller.yml) and [calldatasize](https://github.com/ethereum/tests/blob/81862e4848585a438d64f911a19b3825f0f4cd95/src/GeneralStateTestsFiller/VMTests/vmTests/calldatasizeFiller.yml) tests ([#1236](https://github.com/ethereum/execution-spec-tests/pull/1236)).
 
 ## [v4.1.0](https://github.com/ethereum/execution-spec-tests/releases/tag/v4.1.0) - 2025-03-11
 
diff --git a/tests/frontier/opcodes/test_calldataload.py b/tests/frontier/opcodes/test_calldataload.py
new file mode 100644
index 00000000000..495bb372176
--- /dev/null
+++ b/tests/frontier/opcodes/test_calldataload.py
@@ -0,0 +1,92 @@
+"""test `CALLDATALOAD` opcode."""
+
+import pytest
+
+from ethereum_test_forks import Byzantium, Fork
+from ethereum_test_tools import Account, Alloc, StateTestFiller, Transaction
+from ethereum_test_tools import Macros as Om
+from ethereum_test_tools.vm.opcode import Opcodes as Op
+
+
+@pytest.mark.parametrize(
+    "calldata,calldata_offset,expected_storage",
+    [
+        (
+            b"\x25\x60",
+            0x0,
+            0x2560000000000000000000000000000000000000000000000000000000000000,
+        ),
+        (
+            b"\xff" * 32 + b"\x23",
+            0x1,
+            0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF23,
+        ),
+        (
+            bytes.fromhex("123456789ABCDEF00000000000000000000000000000000000000000000000000024"),
+            0x5,
+            0xBCDEF00000000000000000000000000000000000000000000000000024000000,
+        ),
+    ],
+    ids=[
+        "two_bytes",
+        "word_n_byte",
+        "34_bytes",
+    ],
+)
+def test_calldataload(
+    state_test: StateTestFiller,
+    calldata: bytes,
+    calldata_offset: int,
+    fork: Fork,
+    pre: Alloc,
+    expected_storage: Account,
+):
+    """
+    Test `CALLDATALOAD` opcode.
+
+    Based on https://github.com/ethereum/tests/blob/ae4791077e8fcf716136e70fe8392f1a1f1495fb/src/GeneralStateTestsFiller/VMTests/vmTests/calldatacopyFiller.yml
+    """
+    address_a = pre.deploy_contract(
+        (Op.PUSH1[calldata_offset] + Op.CALLDATALOAD + Op.PUSH1[0x0] + Op.SSTORE + Op.STOP),
+    )
+
+    address_b = pre.deploy_contract(
+        Om.MSTORE(calldata, 0x0)
+        + Op.CALL(
+            gas=Op.SUB(Op.GAS(), 0x100),
+            address=address_a,
+            value=0x0,
+            args_offset=0x0,
+            args_size=len(calldata),
+            ret_offset=0x0,
+            ret_size=0x0,
+        )
+    )
+
+    to = pre.deploy_contract(
+        code=(
+            Op.ADD(0x1000, Op.CALLDATALOAD(offset=0x4))
+            + Op.CALL(
+                gas=Op.SUB(Op.GAS(), 0x100),
+                address=address_b,
+                value=0x0,
+                args_offset=0x0,
+                args_size=0x0,
+                ret_offset=0x0,
+                ret_size=0x0,
+            )
+            + Op.STOP
+        ),
+    )
+
+    tx = Transaction(
+        data=calldata,
+        gas_limit=100_000,
+        protected=fork >= Byzantium,
+        sender=pre.fund_eoa(),
+        to=to,
+    )
+    post = {
+        address_a: Account(storage={0x00: expected_storage}),
+    }
+    state_test(pre=pre, post=post, tx=tx)
diff --git a/tests/frontier/opcodes/test_calldatasize.py b/tests/frontier/opcodes/test_calldatasize.py
new file mode 100644
index 00000000000..b0616c4b120
--- /dev/null
+++ b/tests/frontier/opcodes/test_calldatasize.py
@@ -0,0 +1,50 @@
+"""test `CALLDATASIZE` opcode."""
+
+import pytest
+
+from ethereum_test_forks import Byzantium, Fork
+from ethereum_test_tools import Account, Alloc, StateTestFiller, Transaction
+from ethereum_test_tools import Macros as Om
+from ethereum_test_tools.vm.opcode import Opcodes as Op
+
+
+@pytest.mark.parametrize(
+    "args_size",
+    [0, 2, 16, 33, 257],
+)
+def test_calldataload(
+    state_test: StateTestFiller,
+    fork: Fork,
+    args_size: int,
+    pre: Alloc,
+):
+    """
+    Test `CALLDATASIZE` opcode.
+
+    Based on https://github.com/ethereum/tests/blob/81862e4848585a438d64f911a19b3825f0f4cd95/src/GeneralStateTestsFiller/VMTests/vmTests/calldatasizeFiller.yml
+    """
+    address = pre.deploy_contract(Op.SSTORE(key=0x0, value=Op.CALLDATASIZE))
+
+    to = pre.deploy_contract(
+        code=(
+            Om.MSTORE(b"\x01" * args_size, 0x0)
+            + Op.CALL(
+                gas=Op.SUB(Op.GAS(), 0x100),
+                address=address,
+                value=0x0,
+                args_offset=0x0,
+                args_size=args_size,
+                ret_offset=0x0,
+                ret_size=0x0,
+            )
+        )
+    )
+
+    tx = Transaction(
+        gas_limit=100_000,
+        protected=fork >= Byzantium,
+        sender=pre.fund_eoa(),
+        to=to,
+    )
+    post = {address: Account(storage={0x00: args_size})}
+    state_test(pre=pre, post=post, tx=tx)
diff --git a/tests/homestead/coverage/test_coverage.py b/tests/homestead/coverage/test_coverage.py
index 608cd1284dc..b7240c38a31 100644
--- a/tests/homestead/coverage/test_coverage.py
+++ b/tests/homestead/coverage/test_coverage.py
@@ -41,6 +41,9 @@ def test_coverage(
         + Op.PUSH2(0x0102)
         + Op.PUSH3(0x010203)
         + Op.PUSH4(0x01020304)
+        + Op.PUSH32(0x0101010101010101010101010101010101010101010101010101010101010101)
+        + Op.MSTORE8(0x00, 0x01)
+        + Op.ADD(0x02, 0x03)
         + Op.POP(0x01)
         # lllc tests insert codecopy when using lll(seq())
         + Op.CODECOPY(0, 16, 4),