diff --git a/webapp/packages/core-cli/tests/test.environment.js b/webapp/packages/core-cli/tests/test.environment.js
index 407fcdb17b..bd7ec944f4 100644
--- a/webapp/packages/core-cli/tests/test.environment.js
+++ b/webapp/packages/core-cli/tests/test.environment.js
@@ -12,5 +12,8 @@ module.exports = class CustomTestEnvironment extends Environment {
     this.global.TextDecoder = TextDecoder;
     this.global.Response = Response;
     this.global.Request = Request;
+
+    // different machine has its own timezones and some tests can fail because of it
+    process.env.TZ = 'UTC';
   }
-};
\ No newline at end of file
+};
diff --git a/webapp/packages/core-utils/src/timestampToDate.test.ts b/webapp/packages/core-utils/src/timestampToDate.test.ts
index b8a30001b7..80b307c5da 100644
--- a/webapp/packages/core-utils/src/timestampToDate.test.ts
+++ b/webapp/packages/core-utils/src/timestampToDate.test.ts
@@ -3,16 +3,16 @@ import { timestampToDate } from './timestampToDate';
 describe('timestampToDate', () => {
   it('should convert timestamp to date', () => {
     const date = timestampToDate(1591862400000);
-    expect(date).toBe('6/11/2020, 10:00:00 AM');
+    expect(date).toBe('6/11/2020, 8:00:00 AM');
   });
 
   it('should convert negative timestamp to date', () => {
     const date = timestampToDate(-1591862400000);
-    expect(date).toBe('7/23/1919, 5:00:00 PM');
+    expect(date).toBe('7/23/1919, 4:00:00 PM');
   });
 
   it('should convert zero timestamp to date', () => {
     const date = timestampToDate(0);
-    expect(date).toBe('1/1/1970, 1:00:00 AM');
+    expect(date).toBe('1/1/1970, 12:00:00 AM');
   });
 });