diff --git a/changelog/15743.txt b/changelog/15743.txt
new file mode 100644
index 0000000000000..2e1183649b4b6
--- /dev/null
+++ b/changelog/15743.txt
@@ -0,0 +1,3 @@
+```release-note:bug
+ui: Fixes client count timezone bug
+```
\ No newline at end of file
diff --git a/ui/app/helpers/parse-date-string.js b/ui/app/helpers/parse-date-string.js
index b4780c02c853c..9535153e64784 100644
--- a/ui/app/helpers/parse-date-string.js
+++ b/ui/app/helpers/parse-date-string.js
@@ -8,9 +8,11 @@ export function parseDateString(date, separator = '-') {
     if (datePieces[0] < 1 || datePieces[0] > 12) {
       throw new Error('Not a valid month value');
     }
-    let firstOfMonth = new Date(datePieces[1], datePieces[0] - 1, 1);
-    if (isValid(firstOfMonth)) {
-      return firstOfMonth;
+    // Since backend converts the timezone to UTC, sending the first (1) as start or end date can cause the month to change.
+    // To mitigate this impact of timezone conversion, hard coding the date to avoid month change.
+    let date = new Date(datePieces[1], datePieces[0] - 1, 10);
+    if (isValid(date)) {
+      return date;
     }
   }
   // what to return if not valid?
diff --git a/ui/app/routes/vault/cluster/clients/index.js b/ui/app/routes/vault/cluster/clients/index.js
index f830881389347..e0d3c82b821a1 100644
--- a/ui/app/routes/vault/cluster/clients/index.js
+++ b/ui/app/routes/vault/cluster/clients/index.js
@@ -1,7 +1,7 @@
 import Route from '@ember/routing/route';
 import ClusterRoute from 'vault/mixins/cluster-route';
 import { hash } from 'rsvp';
-import { getTime } from 'date-fns';
+import { formatRFC3339 } from 'date-fns';
 import { parseDateString } from 'vault/helpers/parse-date-string';
 
 const getActivityParams = ({ tab, start, end }) => {
@@ -14,16 +14,13 @@ const getActivityParams = ({ tab, start, end }) => {
     if (start) {
       let startDate = parseDateString(start);
       if (startDate) {
-        // TODO: Replace with formatRFC3339 when date-fns is updated
-        // converts to milliseconds, divide by 1000 to get epoch
-        params.start_time = getTime(startDate) / 1000;
+        params.start_time = formatRFC3339(startDate);
       }
     }
     if (end) {
       let endDate = parseDateString(end);
       if (endDate) {
-        // TODO: Replace with formatRFC3339 when date-fns is updated
-        params.end_time = getTime(endDate) / 1000;
+        params.end_time = formatRFC3339(endDate);
       }
     }
   }
diff --git a/ui/tests/unit/helpers/parse-date-string-test.js b/ui/tests/unit/helpers/parse-date-string-test.js
index 8297a2ab901ba..57242fa7edee1 100644
--- a/ui/tests/unit/helpers/parse-date-string-test.js
+++ b/ui/tests/unit/helpers/parse-date-string-test.js
@@ -4,13 +4,13 @@ import { compareAsc } from 'date-fns';
 
 module('Unit | Helpers | parse-date-string', function() {
   test('it returns the first of the month when date like MM-yyyy passed in', function(assert) {
-    let expected = new Date(2020, 3, 1);
+    let expected = new Date(2020, 3, 10);
     let result = parseDateString('04-2020');
     assert.equal(compareAsc(expected, result), 0);
   });
 
   test('it can handle a date format like MM/yyyy', function(assert) {
-    let expected = new Date(2020, 11, 1);
+    let expected = new Date(2020, 11, 10);
     let result = parseDateString('12/2020', '/');
     assert.equal(compareAsc(expected, result), 0);
   });