diff --git a/pkg/cosmos/txmgr/models.go b/pkg/cosmos/txmgr/models.go
index 15dfb885..35b22c9a 100644
--- a/pkg/cosmos/txmgr/models.go
+++ b/pkg/cosmos/txmgr/models.go
@@ -14,7 +14,7 @@ import (
 	txmgrtypes "github.com/smartcontractkit/chainlink-relay/pkg/txmgr/types"
 )
 
-// Type aliases for Cosmos
+// Type aliases for Cosmos specific implementation of generic txmgr
 type (
 	TxRequest = txmgrtypes.TxRequest[Address, TxHash]
 )
diff --git a/pkg/cosmos/txmgr/models_test.go b/pkg/cosmos/txmgr/models_test.go
new file mode 100644
index 00000000..c78d265d
--- /dev/null
+++ b/pkg/cosmos/txmgr/models_test.go
@@ -0,0 +1,80 @@
+package txmgr
+
+import (
+	"bytes"
+	"testing"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	"github.com/cosmos/cosmos-sdk/x/bank/types"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestEncodeDecodePayload(t *testing.T) {
+	fromAddress, err := sdk.AccAddressFromBech32("cosmos1swp4kg5e3vphyufvllenu4uet6368f88cwcmc0")
+	assert.NoError(t, err)
+	toAddress, err := sdk.AccAddressFromBech32("cosmos153lf4zntqt33a4v0sm5cytrxyqn78q7kz8j8x5")
+	assert.NoError(t, err)
+
+	msgSend := types.MsgSend{
+		FromAddress: fromAddress.String(),
+		ToAddress:   toAddress.String(),
+		Amount:      sdk.NewCoins(sdk.NewCoin("atom", sdk.NewInt(1000))),
+	}
+
+	encoded, err := EncodePayload(&msgSend)
+	assert.NoError(t, err)
+
+	decoded, err := DecodePayload(typeMsgSend, encoded)
+	assert.NoError(t, err)
+
+	assert.Equal(t, &msgSend, decoded)
+}
+
+func TestAddress(t *testing.T) {
+	addr32, err := sdk.AccAddressFromHexUnsafe("b9df9bb7c25b05196fc5a4237eedab76460347da45b7b6bbe5edfa5d396c42a6")
+	assert.NoError(t, err)
+	assert.Equal(t, 32, len(addr32.Bytes()))
+
+	addr20, err := sdk.AccAddressFromBech32("cosmos1swp4kg5e3vphyufvllenu4uet6368f88cwcmc0")
+	assert.NoError(t, err)
+	assert.Equal(t, 20, len(addr20.Bytes()))
+
+	// Test cases
+	testCases := []struct {
+		name       string
+		accAddress sdk.AccAddress
+	}{
+		{
+			name:       "32_bytes_address",
+			accAddress: addr32,
+		},
+		{
+			name:       "20_bytes_address",
+			accAddress: addr20,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name+"_NewAddress", func(t *testing.T) {
+			addr := NewAddress(tc.accAddress)
+			if !bytes.Equal(addr.Bytes()[:len(tc.accAddress)], tc.accAddress) {
+				t.Errorf("NewAddress() = %v, want %v", addr.Bytes(), tc.accAddress)
+			}
+		})
+
+		t.Run(tc.name+"_ToCosmosAddress", func(t *testing.T) {
+			addr := NewAddress(tc.accAddress)
+			cosmosAddr := ToCosmosAddress(addr)
+			if cosmosAddr.String() != tc.accAddress.String() {
+				t.Errorf("ToCosmosAddress() = %v, want %v", cosmosAddr, tc.accAddress)
+			}
+		})
+
+		t.Run(tc.name+"_String", func(t *testing.T) {
+			addr := NewAddress(tc.accAddress)
+			if addr.String() != tc.accAddress.String() {
+				t.Errorf("String() = %v, want %v", addr.String(), tc.accAddress.String())
+			}
+		})
+	}
+}