diff --git a/go/cmd/vttestserver/cli/main.go b/go/cmd/vttestserver/cli/main.go
index 5601623b2fa..aef324043a8 100644
--- a/go/cmd/vttestserver/cli/main.go
+++ b/go/cmd/vttestserver/cli/main.go
@@ -206,7 +206,7 @@ func New() (cmd *cobra.Command) {
 	cmd.Flags().BoolVar(&config.EnableSystemSettings, "enable_system_settings", true, "This will enable the system settings to be changed per session at the database connection level")
 
 	cmd.Flags().StringVar(&config.TransactionMode, "transaction_mode", "MULTI", "Transaction mode MULTI (default), SINGLE or TWOPC ")
-	cmd.Flags().Float64Var(&config.TransactionTimeout, "queryserver-config-transaction-timeout", 0, "query server transaction timeout (in seconds), a transaction will be killed if it takes longer than this value")
+	cmd.Flags().DurationVar(&config.TransactionTimeout, "queryserver-config-transaction-timeout", 30*time.Second, "query server transaction timeout, a transaction will be killed if it takes longer than this value (default 30s)")
 
 	cmd.Flags().StringVar(&config.TabletHostName, "tablet_hostname", "localhost", "The hostname to use for the tablet otherwise it will be derived from OS' hostname")
 
diff --git a/go/flags/endtoend/vttestserver.txt b/go/flags/endtoend/vttestserver.txt
index 8cce76afc65..95c69714e59 100644
--- a/go/flags/endtoend/vttestserver.txt
+++ b/go/flags/endtoend/vttestserver.txt
@@ -106,7 +106,7 @@ Flags:
       --pprof-http                                                       enable pprof http endpoints
       --proto_topo string                                                Define the fake cluster topology as a compact text format encoded vttest proto. See vttest.proto for more information.
       --purge_logs_interval duration                                     how often try to remove old logs (default 1h0m0s)
-      --queryserver-config-transaction-timeout float                     query server transaction timeout (in seconds), a transaction will be killed if it takes longer than this value
+      --queryserver-config-transaction-timeout duration                  query server transaction timeout, a transaction will be killed if it takes longer than this value (default 30s)
       --rdonly_count int                                                 Rdonly tablets per shard (default 1)
       --replica_count int                                                Replica tablets per shard (includes primary) (default 2)
       --replication_connect_retry duration                               how long to wait in between replica reconnect attempts. Only precise to the second. (default 10s)
diff --git a/go/vt/vttest/local_cluster.go b/go/vt/vttest/local_cluster.go
index 3c65f7de1eb..406269ef749 100644
--- a/go/vt/vttest/local_cluster.go
+++ b/go/vt/vttest/local_cluster.go
@@ -128,7 +128,7 @@ type Config struct {
 	// TransactionMode is SINGLE, MULTI or TWOPC
 	TransactionMode string
 
-	TransactionTimeout float64
+	TransactionTimeout time.Duration
 
 	// The host name to use for the table otherwise it will be resolved from the local hostname
 	TabletHostName string
diff --git a/go/vt/vttest/vtprocess.go b/go/vt/vttest/vtprocess.go
index 2d2c9116c6d..c728171963b 100644
--- a/go/vt/vttest/vtprocess.go
+++ b/go/vt/vttest/vtprocess.go
@@ -260,7 +260,7 @@ func VtcomboProcess(environment Environment, args *Config, mysql MySQLManager) (
 		vt.ExtraArgs = append(vt.ExtraArgs, []string{"--transaction_mode", args.TransactionMode}...)
 	}
 	if args.TransactionTimeout != 0 {
-		vt.ExtraArgs = append(vt.ExtraArgs, "--queryserver-config-transaction-timeout", fmt.Sprintf("%f", args.TransactionTimeout))
+		vt.ExtraArgs = append(vt.ExtraArgs, "--queryserver-config-transaction-timeout", fmt.Sprintf("%v", args.TransactionTimeout))
 	}
 	if args.TabletHostName != "" {
 		vt.ExtraArgs = append(vt.ExtraArgs, []string{"--tablet_hostname", args.TabletHostName}...)