diff --git a/app/app_test.go b/app/app_test.go
index e98b8a5a2..7889a31b0 100644
--- a/app/app_test.go
+++ b/app/app_test.go
@@ -44,7 +44,7 @@ func (at *appTest) getTx(seq int, coins coin.Coins) basecoin.Tx {
 	in := []coin.TxInput{{Address: at.acctIn.Actor(), Coins: coins, Sequence: seq}}
 	out := []coin.TxOutput{{Address: at.acctOut.Actor(), Coins: coins}}
 	tx := coin.NewSendTx(in, out)
-	tx = base.NewChainTx(at.chainID, tx)
+	tx = base.NewChainTx(at.chainID, 0, tx)
 	stx := auth.NewMulti(tx)
 	auth.Sign(stx, at.acctIn.Key)
 	return stx.Wrap()
diff --git a/cmd/basecli/commands/cmds.go b/cmd/basecli/commands/cmds.go
index b3c9ede91..e5fff3634 100644
--- a/cmd/basecli/commands/cmds.go
+++ b/cmd/basecli/commands/cmds.go
@@ -34,6 +34,7 @@ const (
 	FlagAmount   = "amount"
 	FlagFee      = "fee"
 	FlagGas      = "gas"
+	FlagExpires  = "expires"
 	FlagSequence = "sequence"
 )
 
@@ -42,7 +43,8 @@ func init() {
 	flags.String(FlagTo, "", "Destination address for the bits")
 	flags.String(FlagAmount, "", "Coins to send in the format <amt><coin>,<amt><coin>...")
 	flags.String(FlagFee, "0mycoin", "Coins for the transaction fee of the format <amt><coin>")
-	flags.Int64(FlagGas, 0, "Amount of gas for this transaction")
+	flags.Uint64(FlagGas, 0, "Amount of gas for this transaction")
+	flags.Int64(FlagExpires, 0, "Block height at which this tx expires")
 	flags.Int(FlagSequence, -1, "Sequence number for this transaction")
 }
 
@@ -63,7 +65,12 @@ func doSendTx(cmd *cobra.Command, args []string) error {
 
 	// TODO: make this more flexible for middleware
 	// add the chain info
-	tx = base.NewChainTx(commands.GetChainID(), tx)
+	tx, err = WrapChainTx(tx)
+	if err != nil {
+		return err
+	}
+
+	// Note: this is single sig (no multi sig yet)
 	stx := auth.NewSig(tx)
 
 	// Sign if needed and post.  This it the work-horse
@@ -76,6 +83,16 @@ func doSendTx(cmd *cobra.Command, args []string) error {
 	return txcmd.OutputTx(bres)
 }
 
+// WrapChainTx will wrap the tx with a ChainTx from the standard flags
+func WrapChainTx(tx basecoin.Tx) (res basecoin.Tx, err error) {
+	expires := viper.GetInt64(FlagExpires)
+	if expires < 0 {
+		return res, errors.New("expires must be >= 0")
+	}
+	res = base.NewChainTx(commands.GetChainID(), uint64(expires), tx)
+	return res, nil
+}
+
 func readSendTxFlags() (tx basecoin.Tx, err error) {
 	// parse to address
 	chain, to, err := parseChainAddress(viper.GetString(FlagTo))
diff --git a/docs/guide/counter/cmd/countercli/commands/counter.go b/docs/guide/counter/cmd/countercli/commands/counter.go
index 255a2f65e..326b62b19 100644
--- a/docs/guide/counter/cmd/countercli/commands/counter.go
+++ b/docs/guide/counter/cmd/countercli/commands/counter.go
@@ -4,13 +4,12 @@ import (
 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
 
-	"github.com/tendermint/basecoin"
-	"github.com/tendermint/light-client/commands"
 	txcmd "github.com/tendermint/light-client/commands/txs"
 
+	"github.com/tendermint/basecoin"
+	bcmd "github.com/tendermint/basecoin/cmd/basecli/commands"
 	"github.com/tendermint/basecoin/docs/guide/counter/plugins/counter"
 	"github.com/tendermint/basecoin/modules/auth"
-	"github.com/tendermint/basecoin/modules/base"
 	"github.com/tendermint/basecoin/modules/coin"
 )
 
@@ -57,7 +56,10 @@ func counterTx(cmd *cobra.Command, args []string) error {
 
 	// TODO: make this more flexible for middleware
 	// add the chain info
-	tx = base.NewChainTx(commands.GetChainID(), tx)
+	tx, err = bcmd.WrapChainTx(tx)
+	if err != nil {
+		return err
+	}
 	stx := auth.NewSig(tx)
 
 	// Sign if needed and post.  This it the work-horse
diff --git a/docs/guide/counter/plugins/counter/counter_test.go b/docs/guide/counter/plugins/counter/counter_test.go
index 522d6a721..2de91d62a 100644
--- a/docs/guide/counter/plugins/counter/counter_test.go
+++ b/docs/guide/counter/plugins/counter/counter_test.go
@@ -42,7 +42,7 @@ func TestCounterPlugin(t *testing.T) {
 	// Deliver a CounterTx
 	DeliverCounterTx := func(valid bool, counterFee coin.Coins, inputSequence int) abci.Result {
 		tx := NewTx(valid, counterFee, inputSequence)
-		tx = base.NewChainTx(chainID, tx)
+		tx = base.NewChainTx(chainID, 0, tx)
 		stx := auth.NewSig(tx)
 		auth.Sign(stx, acct.Key)
 		txBytes := wire.BinaryBytes(stx.Wrap())
diff --git a/modules/base/chain.go b/modules/base/chain.go
index a36226766..4fc7071e6 100644
--- a/modules/base/chain.go
+++ b/modules/base/chain.go
@@ -44,10 +44,19 @@ func (c Chain) DeliverTx(ctx basecoin.Context, store state.KVStore, tx basecoin.
 
 // checkChain makes sure the tx is a Chain Tx and is on the proper chain
 func (c Chain) checkChain(chainID string, tx basecoin.Tx) (basecoin.Tx, error) {
+	// make sure it is a chaintx
 	ctx, ok := tx.Unwrap().(ChainTx)
 	if !ok {
 		return tx, errors.ErrNoChain()
 	}
+
+	// basic validation
+	err := ctx.ValidateBasic()
+	if err != nil {
+		return tx, err
+	}
+
+	// compare against state
 	if ctx.ChainID != chainID {
 		return tx, errors.ErrWrongChain(ctx.ChainID)
 	}