diff --git a/tests/kernel/sched/schedule_api/src/test_sched_timeslice_reset.c b/tests/kernel/sched/schedule_api/src/test_sched_timeslice_reset.c
index e12b5000369..6e51321424b 100644
--- a/tests/kernel/sched/schedule_api/src/test_sched_timeslice_reset.c
+++ b/tests/kernel/sched/schedule_api/src/test_sched_timeslice_reset.c
@@ -19,24 +19,31 @@ static K_THREAD_STACK_ARRAY_DEFINE(tstack, NUM_THREAD, STACK_SIZE);
 K_SEM_DEFINE(sema, 0, NUM_THREAD);
 /*elapsed_slice taken by last thread*/
 static s64_t elapsed_slice;
-/*expected elapsed duration*/
-static s64_t expected_slice[NUM_THREAD] = {
-	HALF_SLICE_SIZE,        /* the ztest native thread taking a half timeslice*/
-	SLICE_SIZE,             /* the spawned thread taking a full timeslice, reset*/
-	SLICE_SIZE              /* the spawned thread taking a full timeslice, reset*/
-};
 static int thread_idx;
 
 static void thread_tslice(void *p1, void *p2, void *p3)
 {
 	s64_t t = k_uptime_delta(&elapsed_slice);
+	s64_t expected_slice_min, expected_slice_max;
+
+	if (thread_idx == 0) {
+		/*thread number 0 releases CPU after HALF_SLICE_SIZE*/
+		expected_slice_min = HALF_SLICE_SIZE;
+		expected_slice_max = HALF_SLICE_SIZE;
+	} else {
+		/*other threads are sliced with tick granulity*/
+		expected_slice_min = __ticks_to_ms(_ms_to_ticks(SLICE_SIZE));
+		expected_slice_max = __ticks_to_ms(_ms_to_ticks(SLICE_SIZE)+1);
+	}
 
 	#ifdef CONFIG_DEBUG
-	TC_PRINT("thread[%d] elapsed slice %lld, ", thread_idx, t);
-	TC_PRINT("expected %lld\n", expected_slice[thread_idx]);
+	TC_PRINT("thread[%d] elapsed slice: %lld, expected: <%lld, %lld>\n",
+		thread_idx, t, expected_slice_min, expected_slice_max);
 	#endif
+
 	/** TESTPOINT: timeslice should be reset for each preemptive thread*/
-	zassert_true(t <= expected_slice[thread_idx], NULL);
+	zassert_true(t >= expected_slice_min, NULL);
+	zassert_true(t <= expected_slice_max, NULL);
 	thread_idx = (thread_idx + 1) % NUM_THREAD;
 
 	u32_t t32 = k_uptime_get_32();
diff --git a/tests/kernel/sched/schedule_api/src/test_slice_scheduling.c b/tests/kernel/sched/schedule_api/src/test_slice_scheduling.c
index 66823057361..4657207dd53 100644
--- a/tests/kernel/sched/schedule_api/src/test_slice_scheduling.c
+++ b/tests/kernel/sched/schedule_api/src/test_slice_scheduling.c
@@ -37,20 +37,23 @@ static void thread_tslice(void *p1, void *p2, void *p3)
 	int thread_parameter = ((int)p1 == (NUM_THREAD - 1)) ? '\n' :
 			       ((int)p1 + 'A');
 
+	s64_t expected_slice_min = __ticks_to_ms(_ms_to_ticks(SLICE_SIZE));
+	s64_t expected_slice_max = __ticks_to_ms(_ms_to_ticks(SLICE_SIZE) + 1);
+
 	while (1) {
 		s64_t tdelta = k_uptime_delta(&elapsed_slice);
-
 		TC_PRINT("%c", thread_parameter);
 		/* Test Fails if thread exceed allocated time slice or
 		 * Any thread is scheduled out of order.
 		 */
-		zassert_true(((tdelta <= SLICE_SIZE) &&
+		zassert_true(((tdelta >= expected_slice_min) &&
+			      (tdelta <= expected_slice_max) &&
 			      ((int)p1 == thread_idx)), NULL);
 		thread_idx = (thread_idx + 1) % (NUM_THREAD);
 		u32_t t32 = k_uptime_get_32();
 
 		/* Keep the current thread busy for more than one slice,
-		 * even though,  when timeslice used up the next thread
+		 * even though, when timeslice used up the next thread
 		 * should be scheduled in.
 		 */
 		while (k_uptime_get_32() - t32 < BUSY_MS) {
@@ -104,9 +107,12 @@ void test_slice_scheduling(void)
 	while (count < ITRERATION_COUNT) {
 		k_uptime_delta(&elapsed_slice);
 
-		/* current thread (ztest native) consumed a half timeslice*/
+		/* Keep the current thread busy for more than one slice,
+		 * even though, when timeslice used up the next thread
+		 * should be scheduled in.
+		 */
 		t32 = k_uptime_get_32();
-		while (k_uptime_get_32() - t32 < SLICE_SIZE) {
+		while (k_uptime_get_32() - t32 < BUSY_MS) {
 #if defined(CONFIG_ARCH_POSIX)
 			posix_halt_cpu(); /*sleep until next irq*/
 #else
diff --git a/tests/kernel/tickless/tickless_concept/src/main.c b/tests/kernel/tickless/tickless_concept/src/main.c
index 6793ce25736..d0b39b97cf3 100644
--- a/tests/kernel/tickless/tickless_concept/src/main.c
+++ b/tests/kernel/tickless/tickless_concept/src/main.c
@@ -15,14 +15,18 @@ static struct k_thread tdata[NUM_THREAD];
 #ifndef CONFIG_TICKLESS_IDLE
 #define CONFIG_TICKLESS_IDLE_THRESH 20
 #endif
-/*millisecond per tick*/
-#define MSEC_PER_TICK (__ticks_to_ms(1))
 /*sleep duration tickless*/
-#define SLEEP_TICKLESS (CONFIG_TICKLESS_IDLE_THRESH * MSEC_PER_TICK)
+#define SLEEP_TICKLESS	 __ticks_to_ms(CONFIG_TICKLESS_IDLE_THRESH)
+
 /*sleep duration with tick*/
-#define SLEEP_TICKFUL ((CONFIG_TICKLESS_IDLE_THRESH - 1) * MSEC_PER_TICK)
+#define SLEEP_TICKFUL	 __ticks_to_ms(CONFIG_TICKLESS_IDLE_THRESH - 1)
+
 /*slice size is set as half of the sleep duration*/
-#define SLICE_SIZE ((CONFIG_TICKLESS_IDLE_THRESH >> 1) * MSEC_PER_TICK)
+#define SLICE_SIZE	 __ticks_to_ms(CONFIG_TICKLESS_IDLE_THRESH >> 1)
+
+/*maximum slice duration accepted by the test*/
+#define SLICE_SIZE_LIMIT __ticks_to_ms((CONFIG_TICKLESS_IDLE_THRESH >> 1) + 1)
+
 /*align to millisecond boundary*/
 #if defined(CONFIG_ARCH_POSIX)
 #define ALIGN_MS_BOUNDARY()		       \
@@ -46,11 +50,13 @@ static void thread_tslice(void *p1, void *p2, void *p3)
 {
 	s64_t t = k_uptime_delta(&elapsed_slice);
 
-	TC_PRINT("elapsed slice %lld\n", t);
+	TC_PRINT("elapsed slice %lld, expected: <%lld, %lld>\n",
+		t, SLICE_SIZE, SLICE_SIZE_LIMIT);
+
 	/**TESTPOINT: verify slicing scheduler behaves as expected*/
 	zassert_true(t >= SLICE_SIZE, NULL);
 	/*less than one tick delay*/
-	zassert_true(t <= (SLICE_SIZE + MSEC_PER_TICK), NULL);
+	zassert_true(t <= SLICE_SIZE_LIMIT, NULL);
 
 	u32_t t32 = k_uptime_get_32();
 
diff --git a/tests/kernel/workq/work_queue/src/main.c b/tests/kernel/workq/work_queue/src/main.c
index eb7e6e9d829..0a86c493ea8 100644
--- a/tests/kernel/workq/work_queue/src/main.c
+++ b/tests/kernel/workq/work_queue/src/main.c
@@ -15,6 +15,10 @@
 /* Each work item takes 100ms */
 #define WORK_ITEM_WAIT          100
 
+/* In fact, each work item could take up to this value */
+#define WORK_ITEM_WAIT_ALIGNED	\
+	__ticks_to_ms(_ms_to_ticks(WORK_ITEM_WAIT) + _TICK_ALIGN)
+
 /*
  * Wait 50ms between work submissions, to ensure co-op and prempt
  * preempt thread submit alternatively.
@@ -139,7 +143,7 @@ static void test_sequence(void)
 	test_items_submit();
 
 	TC_PRINT(" - Waiting for work to finish\n");
-	k_sleep((NUM_TEST_ITEMS + 1) * WORK_ITEM_WAIT);
+	k_sleep(NUM_TEST_ITEMS * WORK_ITEM_WAIT_ALIGNED);
 
 	check_results(NUM_TEST_ITEMS);
 	reset_results();
@@ -179,7 +183,7 @@ static void test_resubmit(void)
 	k_work_submit(&tests[0].work.work);
 
 	TC_PRINT(" - Waiting for work to finish\n");
-	k_sleep((NUM_TEST_ITEMS + 1) * WORK_ITEM_WAIT);
+	k_sleep(NUM_TEST_ITEMS * WORK_ITEM_WAIT_ALIGNED);
 
 	TC_PRINT(" - Checking results\n");
 	check_results(NUM_TEST_ITEMS);
@@ -294,7 +298,7 @@ static void test_delayed_cancel(void)
 			NULL, NULL, NULL, K_HIGHEST_THREAD_PRIO, 0, 0);
 
 	TC_PRINT(" - Waiting for work to finish\n");
-	k_sleep(2 * WORK_ITEM_WAIT);
+	k_sleep(WORK_ITEM_WAIT_ALIGNED);
 
 	TC_PRINT(" - Checking results\n");
 	check_results(0);
@@ -331,7 +335,7 @@ static void test_delayed_resubmit(void)
 	k_delayed_work_submit(&tests[0].work, WORK_ITEM_WAIT);
 
 	TC_PRINT(" - Waiting for work to finish\n");
-	k_sleep((NUM_TEST_ITEMS + 1) * WORK_ITEM_WAIT);
+	k_sleep(NUM_TEST_ITEMS * WORK_ITEM_WAIT_ALIGNED);
 
 	TC_PRINT(" - Checking results\n");
 	check_results(NUM_TEST_ITEMS);
@@ -378,7 +382,7 @@ static void test_delayed_resubmit_thread(void)
 			NULL, NULL, NULL, K_PRIO_COOP(10), 0, 0);
 
 	TC_PRINT(" - Waiting for work to finish\n");
-	k_sleep(WORK_ITEM_WAIT);
+	k_sleep(WORK_ITEM_WAIT_ALIGNED);
 
 	TC_PRINT(" - Checking results\n");
 	check_results(1);
@@ -403,7 +407,7 @@ static void test_delayed(void)
 	test_delayed_submit();
 
 	TC_PRINT(" - Waiting for delayed work to finish\n");
-	k_sleep((NUM_TEST_ITEMS + 2) * WORK_ITEM_WAIT);
+	k_sleep(NUM_TEST_ITEMS * WORK_ITEM_WAIT_ALIGNED);
 
 	TC_PRINT(" - Checking results\n");
 	check_results(NUM_TEST_ITEMS);