diff --git a/x/swaprouter/module/module.go b/x/swaprouter/module/module.go
index 0d4c240277f..e6c7d93b245 100644
--- a/x/swaprouter/module/module.go
+++ b/x/swaprouter/module/module.go
@@ -33,6 +33,7 @@ type AppModuleBasic struct{}
 func (AppModuleBasic) Name() string { return types.ModuleName }
 
 func (AppModuleBasic) RegisterLegacyAminoCodec(cdc *codec.LegacyAmino) {
+	types.RegisterLegacyAminoCodec(cdc)
 }
 
 func (AppModuleBasic) DefaultGenesis(cdc codec.JSONCodec) json.RawMessage {
@@ -69,6 +70,7 @@ func (b AppModuleBasic) GetQueryCmd() *cobra.Command {
 
 // RegisterInterfaces registers interfaces and implementations of the gamm module.
 func (AppModuleBasic) RegisterInterfaces(registry codectypes.InterfaceRegistry) {
+	types.RegisterInterfaces(registry)
 }
 
 type AppModule struct {
@@ -137,8 +139,6 @@ func (AppModule) ConsensusVersion() uint64 { return 1 }
 
 // **** simulation implementation ****
 // GenerateGenesisState creates a randomized GenState of the swaprouter module.
-// **** simulation implementation ****
-// GenerateGenesisState creates a randomized GenState of the gamm module.
 func (am AppModule) SimulatorGenesisState(simState *module.SimulationState, s *simtypes.SimCtx) {
 	swaprouterGen := types.DefaultGenesis()
 	// change the pool creation fee denom from uosmo to stake
@@ -148,7 +148,5 @@ func (am AppModule) SimulatorGenesisState(simState *module.SimulationState, s *s
 }
 
 func (am AppModule) Actions() []simtypes.Action {
-	// TODO: uncomment this once simulation is enabled.
-	// return swaproutersimulation.DefaultActions(am.k, am.gammKeeper)
 	return nil
 }
diff --git a/x/swaprouter/types/codec.go b/x/swaprouter/types/codec.go
new file mode 100644
index 00000000000..7fc9fa6ab65
--- /dev/null
+++ b/x/swaprouter/types/codec.go
@@ -0,0 +1,40 @@
+package types
+
+import (
+	"github.com/cosmos/cosmos-sdk/codec"
+	"github.com/cosmos/cosmos-sdk/codec/types"
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	"github.com/cosmos/cosmos-sdk/types/msgservice"
+	authzcodec "github.com/cosmos/cosmos-sdk/x/authz/codec"
+)
+
+// RegisterLegacyAminoCodec registers the necessary x/gamm interfaces and concrete types
+// on the provided LegacyAmino codec. These types are used for Amino JSON serialization.
+func RegisterLegacyAminoCodec(cdc *codec.LegacyAmino) {
+	cdc.RegisterConcrete(&MsgSwapExactAmountIn{}, "osmosis/swaprouter/swap-exact-amount-in", nil)
+	cdc.RegisterConcrete(&MsgSwapExactAmountOut{}, "osmosis/swaprouter/swap-exact-amount-out", nil)
+}
+
+func RegisterInterfaces(registry types.InterfaceRegistry) {
+	registry.RegisterImplementations(
+		(*sdk.Msg)(nil),
+		&MsgSwapExactAmountIn{},
+		&MsgSwapExactAmountOut{},
+	)
+	msgservice.RegisterMsgServiceDesc(registry, &_Msg_serviceDesc)
+}
+
+var (
+	amino     = codec.NewLegacyAmino()
+	ModuleCdc = codec.NewAminoCodec(amino)
+)
+
+func init() {
+	RegisterLegacyAminoCodec(amino)
+	// Register all Amino interfaces and concrete types on the authz Amino codec so that this can later be
+	// used to properly serialize MsgGrant and MsgExec instances
+	sdk.RegisterLegacyAminoCodec(amino)
+	RegisterLegacyAminoCodec(authzcodec.Amino)
+
+	amino.Seal()
+}
diff --git a/x/swaprouter/types/msgs.go b/x/swaprouter/types/msgs.go
index ed85dd3d35c..c41a69c90e4 100644
--- a/x/swaprouter/types/msgs.go
+++ b/x/swaprouter/types/msgs.go
@@ -38,10 +38,8 @@ func (msg MsgSwapExactAmountIn) ValidateBasic() error {
 	return nil
 }
 
-// TODO: uncomment when types are registered.
 func (msg MsgSwapExactAmountIn) GetSignBytes() []byte {
-	// return sdk.MustSortJSON(ModuleCdc.MustMarshalJSON(&msg))
-	panic("not implemented")
+	return sdk.MustSortJSON(ModuleCdc.MustMarshalJSON(&msg))
 }
 
 func (msg MsgSwapExactAmountIn) GetSigners() []sdk.AccAddress {
@@ -78,10 +76,8 @@ func (msg MsgSwapExactAmountOut) ValidateBasic() error {
 	return nil
 }
 
-// TODO: uncomment when types are registered.
 func (msg MsgSwapExactAmountOut) GetSignBytes() []byte {
-	// return sdk.MustSortJSON(ModuleCdc.MustMarshalJSON(&msg))
-	panic("not implemented")
+	return sdk.MustSortJSON(ModuleCdc.MustMarshalJSON(&msg))
 }
 
 func (msg MsgSwapExactAmountOut) GetSigners() []sdk.AccAddress {
diff --git a/x/swaprouter/types/msgs_test.go b/x/swaprouter/types/msgs_test.go
index bafa98cd88f..92f4ead2e4b 100644
--- a/x/swaprouter/types/msgs_test.go
+++ b/x/swaprouter/types/msgs_test.go
@@ -275,21 +275,17 @@ func TestMsgSwapExactAmountOut(t *testing.T) {
 
 // Test authz serialize and de-serializes for swaprouter msg.
 func TestAuthzMsg(t *testing.T) {
-
-	// TODO: remove when types are registered.
-	t.SkipNow()
-
 	pk1 := ed25519.GenPrivKey().PubKey()
 	addr1 := sdk.AccAddress(pk1.Address()).String()
 	coin := sdk.NewCoin(sdk.DefaultBondDenom, sdk.NewInt(1))
 
 	testCases := []struct {
-		name    string
-		gammMsg sdk.Msg
+		name string
+		msg  sdk.Msg
 	}{
 		{
-			name: "MsgJoinSwapShareAmountOut",
-			gammMsg: &types.MsgSwapExactAmountIn{
+			name: "MsgSwapExactAmountOut",
+			msg: &types.MsgSwapExactAmountIn{
 				Sender: addr1,
 				Routes: []types.SwapAmountInRoute{{
 					PoolId:        0,
@@ -304,7 +300,7 @@ func TestAuthzMsg(t *testing.T) {
 		},
 		{
 			name: "MsgSwapExactAmountOut",
-			gammMsg: &types.MsgSwapExactAmountOut{
+			msg: &types.MsgSwapExactAmountOut{
 				Sender: addr1,
 				Routes: []types.SwapAmountOutRoute{{
 					PoolId:       0,
@@ -320,7 +316,7 @@ func TestAuthzMsg(t *testing.T) {
 	}
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
-			apptesting.TestMessageAuthzSerialization(t, tc.gammMsg)
+			apptesting.TestMessageAuthzSerialization(t, tc.msg)
 		})
 	}
 }