diff --git a/tests/client/message_test.py b/tests/client/message_test.py
new file mode 100644
index 0000000..29a05cf
--- /dev/null
+++ b/tests/client/message_test.py
@@ -0,0 +1,171 @@
+import pytest
+
+from pyband.wallet import PrivateKey
+from pyband.transaction import Transaction
+
+from pyband.proto.cosmos.base.v1beta1.coin_pb2 import Coin
+from pyband.proto.cosmos.bank.v1beta1.tx_pb2 import MsgSend
+
+# Servicer
+from pyband.proto.cosmos.tx.v1beta1.service_pb2_grpc import (
+    ServiceServicer as CosmosTxServicerBase,
+)
+
+# Types
+from pyband.proto.cosmos.tx.v1beta1.service_pb2 import (
+    BroadcastTxRequest,
+    BroadcastTxResponse,
+)
+from pyband.proto.cosmos.base.abci.v1beta1.abci_pb2 import TxResponse
+
+MNEMONIC = "s"
+PRIVATE_KEY = PrivateKey.from_mnemonic(MNEMONIC)
+PUBLIC_KEY = PRIVATE_KEY.to_public_key()
+ADDRESS = PUBLIC_KEY.to_address()
+SENDER = ADDRESS.to_acc_bech32()
+
+success_msg = MsgSend(
+    from_address=SENDER,
+    to_address="band1d77h06hmw5r8gqh2nnf8msx48f3cc6rqt6pt8l",
+    amount=[Coin(amount="10000", denom="uband")],
+)
+invalid_sender_msg = MsgSend(
+    from_address="123",
+    to_address="band1d77h06hmw5r8gqh2nnf8msx48f3cc6rqt6pt8l",
+    amount=[Coin(amount="10000", denom="uband")],
+)
+invalid_recipient_msg = MsgSend(
+    from_address=SENDER,
+    to_address="123",
+    amount=[Coin(amount="10000", denom="uband")],
+)
+invalid_coins_msg = MsgSend(
+    from_address=SENDER,
+    to_address="band1d77h06hmw5r8gqh2nnf8msx48f3cc6rqt6pt8l",
+    amount=[Coin(amount="-10000", denom="uband")],
+)
+
+
+def getTxBytes(msg):
+    t = (
+        Transaction()
+        .with_messages(msg)
+        .with_account_num(100)
+        .with_sequence(30)
+        .with_chain_id("bandchain")
+    )
+    sign_doc = t.get_sign_doc()
+    signature = PRIVATE_KEY.sign(sign_doc.SerializeToString())
+    tx_raw_bytes = t.get_tx_data(signature)
+    return tx_raw_bytes
+
+
+class CosmosTransactionServicer(CosmosTxServicerBase):
+    def BroadcastTx(self, request: BroadcastTxRequest, context) -> BroadcastTxResponse:
+        if request.tx_bytes == getTxBytes(success_msg):
+            return BroadcastTxResponse(
+                tx_response=TxResponse(
+                    height=3278495,
+                    txhash="B75F4352E285F6997237BAA5524165D531C97759EE39DE1B2C73E89C42762C3D",
+                    data="0A1E0A1C2F636F736D6F732E62616E6B2E763162657461312E4D736753656E64",
+                )
+            )
+        elif request.tx_bytes == getTxBytes(invalid_sender_msg):
+            return BroadcastTxResponse(
+                tx_response=TxResponse(
+                    txhash="6252299B8DF1A024F707E10B77627331FF9303CE0E6D6B3DC68F9CCB9BF742F9",
+                    codespace="sdk",
+                    code=7,
+                    raw_log="Invalid sender address (decoding bech32 failed: invalid bech32 string length 3): invalid address",
+                )
+            )
+        elif request.tx_bytes == getTxBytes(invalid_recipient_msg):
+            return BroadcastTxResponse(
+                tx_response=TxResponse(
+                    txhash="88588BCB2B8813E51EE5EC5DFBB831B37C5C9C5B6528BBC333D7E9AA49110194",
+                    codespace="sdk",
+                    code=7,
+                    raw_log="Invalid recipient address (decoding bech32 failed: invalid bech32 string length 3): invalid address",
+                )
+            )
+        elif request.tx_bytes == getTxBytes(invalid_coins_msg):
+            return BroadcastTxResponse(
+                tx_response=TxResponse(
+                    txhash="7E66D52CE4E39D2A730B2EB4EC15E8D0A923D861C895D3B208300E74A7C459CE",
+                    codespace="sdk",
+                    code=10,
+                    raw_log="-10000uband: invalid coins",
+                )
+            )
+
+
+@pytest.fixture(scope="module")
+def pyband_client(_grpc_server, grpc_addr):
+    from pyband.proto.cosmos.tx.v1beta1.service_pb2_grpc import (
+        add_ServiceServicer_to_server as add_cosmos_tx,
+    )
+
+    add_cosmos_tx(CosmosTransactionServicer(), _grpc_server)
+
+    _grpc_server.add_insecure_port(grpc_addr)
+    _grpc_server.start()
+
+    from pyband.client import Client
+
+    yield Client(grpc_addr, insecure=True)
+    _grpc_server.stop(grace=None)
+
+
+def test_message_success(pyband_client):
+    tx_response = pyband_client.send_tx_block_mode(getTxBytes(success_msg))
+    mock_result = BroadcastTxResponse(
+        tx_response=TxResponse(
+            height=3278495,
+            txhash="B75F4352E285F6997237BAA5524165D531C97759EE39DE1B2C73E89C42762C3D",
+            data="0A1E0A1C2F636F736D6F732E62616E6B2E763162657461312E4D736753656E64",
+        )
+    )
+
+    assert tx_response == mock_result.tx_response
+
+
+def test_message_invalid_sender(pyband_client):
+    tx_response = pyband_client.send_tx_block_mode(getTxBytes(invalid_sender_msg))
+    mock_result = BroadcastTxResponse(
+        tx_response=TxResponse(
+            txhash="6252299B8DF1A024F707E10B77627331FF9303CE0E6D6B3DC68F9CCB9BF742F9",
+            codespace="sdk",
+            code=7,
+            raw_log="Invalid sender address (decoding bech32 failed: invalid bech32 string length 3): invalid address",
+        )
+    )
+
+    assert tx_response == mock_result.tx_response
+
+
+def test_message_invalid_recipient(pyband_client):
+    tx_response = pyband_client.send_tx_block_mode(getTxBytes(invalid_recipient_msg))
+    mock_result = BroadcastTxResponse(
+        tx_response=TxResponse(
+            txhash="88588BCB2B8813E51EE5EC5DFBB831B37C5C9C5B6528BBC333D7E9AA49110194",
+            codespace="sdk",
+            code=7,
+            raw_log="Invalid recipient address (decoding bech32 failed: invalid bech32 string length 3): invalid address",
+        )
+    )
+
+    assert tx_response == mock_result.tx_response
+
+
+def test_message_invalid_coins(pyband_client):
+    tx_response = pyband_client.send_tx_block_mode(getTxBytes(invalid_coins_msg))
+    mock_result = BroadcastTxResponse(
+        tx_response=TxResponse(
+            txhash="7E66D52CE4E39D2A730B2EB4EC15E8D0A923D861C895D3B208300E74A7C459CE",
+            codespace="sdk",
+            code=10,
+            raw_log="-10000uband: invalid coins",
+        )
+    )
+
+    assert tx_response == mock_result.tx_response