diff --git a/bmc_epoch.cpp b/bmc_epoch.cpp
index c043df4..c06c464 100644
--- a/bmc_epoch.cpp
+++ b/bmc_epoch.cpp
@@ -24,6 +24,7 @@
 {
 namespace server = sdbusplus::xyz::openbmc_project::Time::server;
 using namespace phosphor::logging;
+using namespace sdbusplus::xyz::openbmc_project::Common::Error;
 
 BmcEpoch::BmcEpoch(sdbusplus::bus::bus& bus,
                    const char* objPath)
@@ -107,8 +108,7 @@
     if (timeOwner == Owner::Host)
     {
         log<level::ERR>("Setting BmcTime with HOST owner is not allowed");
-        // TODO: throw NotAllowed exception
-        return 0;
+        elog<InsufficientPermission>();
     }
 
     auto time = microseconds(value);
diff --git a/host_epoch.cpp b/host_epoch.cpp
index 8415f15..ea3026c 100644
--- a/host_epoch.cpp
+++ b/host_epoch.cpp
@@ -1,12 +1,15 @@
 #include "host_epoch.hpp"
 #include "utils.hpp"
 
+#include <phosphor-logging/elog-errors.hpp>
 #include <phosphor-logging/log.hpp>
+#include <xyz/openbmc_project/Common/error.hpp>
 
 namespace phosphor
 {
 namespace time
 {
+using namespace sdbusplus::xyz::openbmc_project::Common::Error;
 using namespace sdbusplus::xyz::openbmc_project::Time;
 using namespace phosphor::logging;
 using namespace std::chrono;
@@ -51,8 +54,7 @@
          && (timeOwner == Owner::Host || timeOwner == Owner::Both)))
     {
         log<level::ERR>("Setting HostTime is not allowed");
-        // TODO: throw NotAllowed exception
-        return 0;
+        elog<InsufficientPermission>();
     }
 
     auto time = microseconds(value);
diff --git a/test/TestBmcEpoch.cpp b/test/TestBmcEpoch.cpp
index 32592e6..2d0bc72 100644
--- a/test/TestBmcEpoch.cpp
+++ b/test/TestBmcEpoch.cpp
@@ -1,12 +1,13 @@
-#include <sdbusplus/bus.hpp>
-#include <gtest/gtest.h>
-#include <memory>
-
 #include "bmc_epoch.hpp"
 #include "config.h"
 #include "types.hpp"
 #include "mocked_bmc_time_change_listener.hpp"
 
+#include <gtest/gtest.h>
+#include <memory>
+#include <sdbusplus/bus.hpp>
+#include <xyz/openbmc_project/Common/error.hpp>
+
 namespace phosphor
 {
 namespace time
@@ -14,6 +15,8 @@
 
 using ::testing::_;
 using namespace std::chrono;
+using InsufficientPermission =
+    sdbusplus::xyz::openbmc_project::Common::Error::InsufficientPermission;
 
 class TestBmcEpoch : public testing::Test
 {
@@ -88,8 +91,9 @@
     // In Host owner, setting time is not allowed
     setTimeMode(Mode::Manual);
     setTimeOwner(Owner::Host);
-    auto ret = bmcEpoch->elapsed(epochNow);
-    EXPECT_EQ(0, ret);
+    EXPECT_THROW(
+        bmcEpoch->elapsed(epochNow),
+        InsufficientPermission);
 }
 
 TEST_F(TestBmcEpoch, setElapsedOK)
diff --git a/test/TestHostEpoch.cpp b/test/TestHostEpoch.cpp
index a492b9a..6c460ad 100644
--- a/test/TestHostEpoch.cpp
+++ b/test/TestHostEpoch.cpp
@@ -1,11 +1,14 @@
-#include <sdbusplus/bus.hpp>
-#include <gtest/gtest.h>
-
 #include "host_epoch.hpp"
 #include "utils.hpp"
 #include "config.h"
 #include "types.hpp"
 
+#include <xyz/openbmc_project/Common/error.hpp>
+
+#include <sdbusplus/bus.hpp>
+#include <gtest/gtest.h>
+
+
 namespace phosphor
 {
 namespace time
@@ -13,6 +16,8 @@
 
 using namespace std::chrono;
 using namespace std::chrono_literals;
+using InsufficientPermission =
+    sdbusplus::xyz::openbmc_project::Common::Error::InsufficientPermission;
 
 const constexpr microseconds USEC_ZERO{0};
 
@@ -73,9 +78,10 @@
             // Set time is not allowed,
             // so verify offset is still 0 after set time
             microseconds diff = 1min;
-            hostEpoch.elapsed(hostEpoch.elapsed() + diff.count());
+            EXPECT_THROW(
+                hostEpoch.elapsed(hostEpoch.elapsed() + diff.count()),
+                InsufficientPermission);
             EXPECT_EQ(0, getOffset().count());
-            // TODO: when gmock is ready, check there is no call to timedatectl
         }
 
         void checkSetSplitTimeInFuture()