diff --git a/sim_test.go b/sim_test.go
index 4427ec8583b3..5ea553e3e2a4 100644
--- a/sim_test.go
+++ b/sim_test.go
@@ -46,6 +46,7 @@ func init() {
 	flag.IntVar(&period, "Period", 1, "run slow invariants only once every period assertions")
 	flag.BoolVar(&onOperation, "SimulateEveryOperation", false, "run slow invariants every operation")
 	flag.BoolVar(&allInvariants, "PrintAllInvariants", false, "print all invariants if a broken invariant is found")
+	flag.Int64Var(&genesisTime, "GenesisTime", 0, "override genesis UNIX time instead of using a random UNIX time")
 }
 
 // helper function for populating input for SimulateFromSeed
@@ -63,11 +64,17 @@ func getSimulateFromSeedInput(tb testing.TB, w io.Writer, app *SimApp) (
 }
 
 func appStateFn(
-	r *rand.Rand, accs []simulation.Account, genesisTimestamp time.Time,
-) (appState json.RawMessage, simAccs []simulation.Account, chainID string) {
+	r *rand.Rand, accs []simulation.Account,
+) (appState json.RawMessage, simAccs []simulation.Account, chainID string, genesisTimestamp time.Time) {
 
 	cdc := MakeCodec()
 
+	if genesisTime == 0 {
+		genesisTimestamp = simulation.RandTimestamp(r)
+	} else {
+		genesisTimestamp = time.Unix(genesisTime, 0)
+	}
+
 	switch {
 	case paramsFile != "" && genesisFile != "":
 		panic("cannot provide both a genesis file and a params file")
@@ -90,7 +97,7 @@ func appStateFn(
 		appState, simAccs, chainID = appStateRandomizedFn(r, accs, genesisTimestamp, appParams)
 	}
 
-	return appState, simAccs, chainID
+	return appState, simAccs, chainID, genesisTimestamp
 }
 
 // TODO refactor out random initialization code to the modules
diff --git a/utils.go b/utils.go
index f3e5d26e1047..4fa1dd24b1d3 100644
--- a/utils.go
+++ b/utils.go
@@ -52,6 +52,7 @@ var (
 	period             int
 	onOperation        bool // TODO Remove in favor of binary search for invariant violation
 	allInvariants      bool
+	genesisTime        int64
 )
 
 // NewSimAppUNSAFE is used for debugging purposes only.