diff --git a/src/tests/time-base-api-test/time-base-api-test.c b/src/tests/time-base-api-test/time-base-api-test.c
new file mode 100644
index 000000000..2f30782c7
--- /dev/null
+++ b/src/tests/time-base-api-test/time-base-api-test.c
@@ -0,0 +1,278 @@
+/*
+ *      Copyright (c) 2020, United States government as represented by the
+ *      administrator of the National Aeronautics Space Administration.
+ *      All rights reserved. This software was created at NASA Goddard
+ *      Space Flight Center pursuant to government contracts.
+ *
+ *      This is governed by the NASA Open Source Agreement and may be used,
+ *      distributed and modified only according to the terms of that agreement.
+ */
+
+/*
+ * Filename: time-base-api-test.c
+ *
+ * Purpose: This file contains functional tests for "osapi-timebase"
+ *
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+
+#include "common_types.h"
+#include "osapi.h"
+#include "utassert.h"
+#include "uttest.h"
+#include "utbsp.h"
+
+static uint32 TimerSyncCount = 0;
+static uint32 TimerSyncRetVal = 0;
+
+static uint32 UT_TimerSync(uint32 timer_id)
+{
+    ++TimerSyncCount;
+    return TimerSyncRetVal;
+}
+
+
+/* *************************************** MAIN ************************************** */
+
+void TestTimeBaseApi(void)
+{
+    int32 expected;
+    int32 actual; 
+    int32 TimeBaseNum;
+    uint32 freerun;
+    uint32 objid;
+    uint32 time_base_id; 
+    uint32 time_base_id2; 
+    char maxTimeBase[12];
+    char overMaxTimeBase[12];
+    OS_timebase_prop_t timebase_prop;
+
+    /*
+     * Test Case For:
+     * int32 OS_TimeBaseCreate(uint32 *timer_id, const char *timebase_name, OS_TimerSync_t external_sync)
+     */
+
+    /* Test for nominal inputs */
+    expected = OS_SUCCESS;
+
+    actual= OS_TimeBaseCreate(&time_base_id, "TimeBase", 0);
+    UtAssert_True(actual == expected, "OS_TimeBaseCreate() (%ld) == OS_SUCCESS", (long)actual);
+
+    actual = OS_TimeBaseCreate(&time_base_id2, "TimeBase2", NULL);
+    UtAssert_True(actual == expected, "OS_TimeBaseCreate() (%ld) == OS_SUCCESS", (long)actual);
+
+    actual = OS_TimeBaseCreate(&time_base_id, "TimeBase3", UT_TimerSync);
+    UtAssert_True(actual == expected, "OS_TimeBaseCreate() (%ld) == OS_SUCCESS", (long)actual);
+
+    /* Test for nominal, max/min cases */
+    objid = 0xFFFFFFFF;
+    actual = OS_TimeBaseCreate(&objid, "TimeBase4", 0);
+    UtAssert_True(actual == expected, "OS_TimeBaseCreate() (%ld) == OS_SUCCESS", (long)actual);
+
+    /* 
+     * Note: OS_MAX_TIMEBASES = 5, so no more than 5 TimeBase IDs are allowed 
+     * Checking for OS_MAX_TIMEBASES:
+     */
+    TimeBaseNum = OS_MAX_TIMEBASES;
+    snprintf(maxTimeBase, 12, "TimeBase%d", TimeBaseNum);
+    objid = 0x00000000;
+    actual = OS_TimeBaseCreate(&objid, "maxTimeBase", 0);
+    UtAssert_True(actual == expected, "OS_TimeBaseCreate() (%ld) == OS_SUCCESS", (long)actual);
+
+
+    /* Test for invalid inputs */
+    expected = OS_INVALID_POINTER;
+    actual = OS_TimeBaseCreate(NULL, NULL, NULL);
+    UtAssert_True(actual == expected, "OS_TimeBaseCreate() (%ld) == OS_INVALID_POINTER", (long)actual);
+
+    expected = OS_INVALID_POINTER;
+    actual = OS_TimeBaseCreate(NULL, "TimeBase6", 0);
+    UtAssert_True(actual == expected, "OS_TimeBaseCreate() (%ld) == OS_INVALID_POINTER", (long)actual);
+
+    expected = OS_INVALID_POINTER;
+    actual = OS_TimeBaseCreate(&time_base_id, NULL, 0);
+    UtAssert_True(actual == expected, "OS_TimeBaseCreate() (%ld) == OS_INVALID_POINTER", (long)actual);
+
+    expected = OS_ERR_NAME_TAKEN;
+    actual= OS_TimeBaseCreate(&time_base_id, "TimeBase", 0);
+    UtAssert_True(actual == expected, "OS_TimeBaseCreate() (%ld) == OS_ERR_NAME_TAKEN", (long)actual);
+
+    /* OS_MAX_TIMEBASES + 1 */
+    TimeBaseNum = OS_MAX_TIMEBASES+1;
+    snprintf(overMaxTimeBase, 12, "TimeBase%d", TimeBaseNum);
+    expected = OS_ERR_NO_FREE_IDS;
+    actual= OS_TimeBaseCreate(&time_base_id, "overMaxTimeBase", 0);
+    UtAssert_True(actual == expected, "OS_TimeBaseCreate() (%ld) == OS_ERR_NO_FREE_IDS", (long)actual);
+
+
+    /*
+     * Test Case For:
+     * int32 OS_TimeBaseSet(uint32 timer_id, uint32 start_time, uint32 interval_time)
+     */
+
+    /* Test for nominal inputs */
+    expected = OS_SUCCESS;
+    actual = OS_TimeBaseSet(time_base_id, 1000, 1000);
+    UtAssert_True(actual == expected, "OS_TimeBaseSet() (%ld) == OS_SUCCESS", (long)actual);
+
+    expected = OS_SUCCESS;
+    actual = OS_TimeBaseSet(time_base_id, 0, 0);
+    UtAssert_True(actual == expected, "OS_TimeBaseSet() (%ld) == OS_SUCCESS", (long)actual);
+
+    /* Test for invalid inputs */
+    /* overflow on input */
+    expected = OS_TIMER_ERR_INVALID_ARGS;
+    actual = OS_TimeBaseSet(time_base_id, UINT32_MAX, UINT32_MAX);
+    UtAssert_True(actual == expected, "OS_TimeBaseSet() (%ld) == OS_TIMER_ERR_INVALID_ARGS", (long)actual);
+
+    expected = OS_TIMER_ERR_INVALID_ARGS;
+    actual = OS_TimeBaseSet(time_base_id, -1000, -1000);
+    UtAssert_True(actual == expected, "OS_TimeBaseSet() (%ld) == OS_TIMER_ERR_INVALID_ARGS", (long)actual);
+
+    expected = OS_TIMER_ERR_INVALID_ARGS;
+    actual = OS_TimeBaseSet(time_base_id, 1000, -1000);
+    UtAssert_True(actual == expected, "OS_TimeBaseSet() (%ld) == OS_TIMER_ERR_INVALID_ARGS", (long)actual);
+
+    expected = OS_TIMER_ERR_INVALID_ARGS;
+    actual = OS_TimeBaseSet(time_base_id, -1000, 1000);
+    UtAssert_True(actual == expected, "OS_TimeBaseSet() (%ld) == OS_TIMER_ERR_INVALID_ARGS", (long)actual);
+
+    expected = OS_ERR_INVALID_ID;
+    actual = OS_TimeBaseSet(0, 1000, 1000);
+    UtAssert_True(actual == expected, "OS_TimeBaseSet() (%ld) == OS_ERR_INVALID_ID", (long)actual);
+
+
+    /*
+     * Test Case For:
+     * int32 OS_TimeBaseDelete(uint32 timer_id)
+     */
+
+    /* Test for nominal inputs */
+    expected = OS_SUCCESS;
+    actual = OS_TimeBaseDelete(time_base_id);
+    UtAssert_True(actual == expected, "OS_TimeBaseDelete() (%ld) == OS_SUCCESS", (long)actual);
+
+    /* Test for invalid inputs */
+    expected = OS_ERR_INVALID_ID;
+    actual = OS_TimeBaseDelete(0x0000000);
+    UtAssert_True(actual == expected, "OS_TimeBaseDelete() (%ld) == OS_ERR_INVALID_ID", (long)actual);
+
+    expected = OS_ERR_INVALID_ID;
+    actual = OS_TimeBaseDelete(0xFFFFFFF);
+    UtAssert_True(actual == expected, "OS_TimeBaseDelete() (%ld) == OS_ERR_INVALID_ID", (long)actual);
+
+    /*
+     * Test Case For:
+     * int32 OS_TimeBaseGetIdByName (uint32 *timer_id, const char *timebase_name)
+     */
+
+    /* Test for nominal inputs */
+    /* Note: TimeBase2 was created above using TimeBaseCreate and id was set to time_base_id2 */
+    expected = OS_SUCCESS;
+    objid = 0;
+    actual = OS_TimeBaseGetIdByName(&objid, "TimeBase2");
+    UtAssert_True(actual == expected, "OS_TimeBaseGetIdByName() (%ld) == OS_SUCCESS", (long)actual);
+    UtAssert_True(objid == time_base_id2, "OS_TimeBaseGetIdByName() objid (%lu) Matches!", (unsigned long)objid);
+
+
+    /* Test for invalid inputs */
+    expected = OS_ERR_NAME_NOT_FOUND;
+    objid = 0;
+    actual = OS_TimeBaseGetIdByName(&objid, "NF");
+    UtAssert_True(actual == expected, "OS_TimeBaseGetIdByName() (%ld) == OS_ERR_NAME_NOT_FOUND",(long)actual);
+    UtAssert_True(objid == 0, "OS_TimeBaseGetIdByName() objid (%lu) still 0", (unsigned long)objid);
+
+    expected = OS_INVALID_POINTER;
+    actual = OS_TimeBaseGetIdByName(NULL, NULL);
+    UtAssert_True(actual == expected, "OS_TimeBaseGetIdByName() (%ld) == OS_INVALID_POINTER", (long)actual);
+
+
+    /*
+     * Test Case For:
+     * int32 OS_TimeBaseGetInfo (uint32 timebase_id, OS_timebase_prop_t *timebase_prop)
+     */
+    expected = OS_SUCCESS;
+
+    /* Test for nominal inputs */
+    /* Note: TimeBase2 was created above using TimeBaseCreate */
+
+    /* Initializing timebase_prop values to something other than time_base_id2 to ensure they have changed */
+    timebase_prop.creator = 1111;
+    strncpy(timebase_prop.name, "ABC", sizeof(
+timebase_prop.name));
+    timebase_prop.nominal_interval_time = 2222;
+    timebase_prop.freerun_time = 3333;
+    timebase_prop.accuracy = 0;
+
+    actual = OS_TimeBaseGetInfo(time_base_id2, &timebase_prop);
+
+    UtAssert_True(actual == expected, "OS_TimeBaseGetInfo() (%ld) == OS_SUCCESS", (long)actual);
+
+    UtAssert_True(timebase_prop.creator == 0, "timebase_prop.creator (%lu) == 0",
+            (unsigned long)timebase_prop.creator);
+    UtAssert_True(strcmp(timebase_prop.name, "TimeBase2") == 0, "timebase_prop.name (%s) == TimeBase2",
+            timebase_prop.name);
+    UtAssert_True(timebase_prop.nominal_interval_time == 0,
+            "timebase_prop.nominal_interval_time (%lu) == 0",
+            (unsigned long)timebase_prop.nominal_interval_time);
+    UtAssert_True(timebase_prop.freerun_time == 0,
+            "timebase_prop.freerun_time (%lu) == 0",
+            (unsigned long)timebase_prop.freerun_time);
+    UtAssert_True(timebase_prop.accuracy >= 0,
+            "timebase_prop.accuracy (%lu) >= 0",
+            (unsigned long)timebase_prop.accuracy);
+
+    /* Test for invalid inputs */
+    expected = OS_ERR_INVALID_ID;
+    actual = OS_TimeBaseGetInfo(1, &timebase_prop);
+    UtAssert_True(actual == expected, "OS_TimeBaseGetInfo() (%ld) == OS_ERR_INVALID_ID", (long)actual);
+
+    expected = OS_INVALID_POINTER;
+    actual = OS_TimeBaseGetInfo(time_base_id2, NULL);
+    UtAssert_True(actual == expected, "OS_TimeBaseGetInfo() (%ld) == OS_INVALID_POINTER", (long)actual);
+
+    /*
+     * Test Case For:
+     * int32 OS_TimeBaseGetFreeRun     (uint32 timebase_id, uint32 *freerun_val)
+     */
+
+    /* Test for nominal inputs */
+    /* Note: TimeBase2 was created above using TimeBaseCreate */
+    expected = OS_SUCCESS;
+
+    freerun = 0xFFFFFFFF;
+    actual = OS_TimeBaseGetFreeRun(time_base_id2, &freerun);
+    UtAssert_True(actual == expected, "OS_TimeBaseGetFreeRun() (%ld) == OS_SUCCESS", (long)actual);
+
+    freerun = 0x0000000;
+    actual = OS_TimeBaseGetFreeRun(time_base_id2, &freerun);
+    UtAssert_True(actual == expected, "OS_TimeBaseGetFreeRun() (%ld) == OS_SUCCESS", (long)actual);
+
+    /* Test for invalid inputs */
+    expected = OS_ERR_INVALID_ID;
+    freerun = 0xFFFFFFFF;
+    actual = OS_TimeBaseGetFreeRun(1, &freerun);
+    UtAssert_True(actual == expected, "OS_TimeBaseGetFreeRun() (%ld) == OS_SUCCESS", (long)actual);
+
+
+
+
+} /* end TestTimeBaseApi */
+
+
+void UtTest_Setup(void)
+{
+    if (OS_API_Init() != OS_SUCCESS)
+    {
+        UtAssert_Abort("OS_API_Init() failed");
+    }
+
+    /*
+     * Register the test setup and check routines in UT assert
+     */
+    UtTest_Add(TestTimeBaseApi, NULL, NULL, "TestTimeBaseApi");
+}
+