diff --git a/src/libs/UserUtils.ts b/src/libs/UserUtils.ts
index 29a43bcf711d..e95b62cc2437 100644
--- a/src/libs/UserUtils.ts
+++ b/src/libs/UserUtils.ts
@@ -1,9 +1,13 @@
 import Str from 'expensify-common/lib/str';
+import _ from 'lodash';
+import Onyx, {OnyxEntry} from 'react-native-onyx';
 import {SvgProps} from 'react-native-svg';
 import {ValueOf} from 'type-fest';
 import * as defaultAvatars from '@components/Icon/DefaultAvatars';
 import {ConciergeAvatar, FallbackAvatar} from '@components/Icon/Expensicons';
 import CONST from '@src/CONST';
+import ONYXKEYS from '@src/ONYXKEYS';
+import {PersonalDetails} from '@src/types/onyx';
 import Login from '@src/types/onyx/Login';
 import hashCode from './hashCode';
 
@@ -13,6 +17,12 @@ type AvatarSource = React.FC<SvgProps> | string;
 
 type LoginListIndicator = ValueOf<typeof CONST.BRICK_ROAD_INDICATOR_STATUS> | '';
 
+let allPersonalDetails: OnyxEntry<Record<string, PersonalDetails>>;
+Onyx.connect({
+    key: ONYXKEYS.PERSONAL_DETAILS_LIST,
+    callback: (val) => (allPersonalDetails = _.isEmpty(val) ? {} : val),
+});
+
 /**
  * Searches through given loginList for any contact method / login with an error.
  *
@@ -68,12 +78,19 @@ function hashText(text: string, range: number): number {
     return Math.abs(hashCode(text.toLowerCase())) % range;
 }
 
+/**
+ * Generate a random accountID base on searchValue.
+ */
+function generateAccountID(searchValue: string): number {
+    return hashText(searchValue, 2 ** 32);
+}
+
 /**
  * Helper method to return the default avatar associated with the given accountID
  * @param [accountID]
  * @returns
  */
-function getDefaultAvatar(accountID = -1): React.FC<SvgProps> {
+function getDefaultAvatar(accountID = -1, avatarURL?: string): React.FC<SvgProps> {
     if (accountID <= 0) {
         return FallbackAvatar;
     }
@@ -83,22 +100,35 @@ function getDefaultAvatar(accountID = -1): React.FC<SvgProps> {
 
     // There are 24 possible default avatars, so we choose which one this user has based
     // on a simple modulo operation of their login number. Note that Avatar count starts at 1.
-    const accountIDHashBucket = ((accountID % CONST.DEFAULT_AVATAR_COUNT) + 1) as AvatarRange;
 
+    // When creating a chat, we generate an avatar using an ID and the backend response will modify the ID to the actual user ID.
+    // But the avatar link still corresponds to the original ID-generated link. So we extract the SVG image number from the backend's link instead of using the user ID directly
+    let accountIDHashBucket: AvatarRange;
+    if (avatarURL) {
+        const match = avatarURL.match(/(?<=default-avatar_)\d+(?=\.)/);
+        const lastDigit = match && parseInt(match[0], 10);
+        accountIDHashBucket = lastDigit as AvatarRange;
+    } else {
+        accountIDHashBucket = ((accountID % CONST.DEFAULT_AVATAR_COUNT) + 1) as AvatarRange;
+    }
     return defaultAvatars[`Avatar${accountIDHashBucket}`];
 }
 
 /**
  * Helper method to return default avatar URL associated with login
  */
-function getDefaultAvatarURL(accountID: string | number = '', isNewDot = false): string {
+function getDefaultAvatarURL(accountID: string | number = ''): string {
     if (Number(accountID) === CONST.ACCOUNT_ID.CONCIERGE) {
         return CONST.CONCIERGE_ICON_URL;
     }
+    // To ensure that the avatar remains unchanged and matches the one returned by the backend,
+    // utilize an optimistic ID generated from the email instead of directly using the user ID.
+    const email = allPersonalDetails?.[accountID]?.login;
+    const originalOptimisticAccountID = email ? generateAccountID(email) : accountID;
 
     // Note that Avatar count starts at 1 which is why 1 has to be added to the result (or else 0 would result in a broken avatar link)
-    const accountIDHashBucket = (Number(accountID) % (isNewDot ? CONST.DEFAULT_AVATAR_COUNT : CONST.OLD_DEFAULT_AVATAR_COUNT)) + 1;
-    const avatarPrefix = isNewDot ? `default-avatar` : `avatar`;
+    const accountIDHashBucket = (Number(originalOptimisticAccountID) % CONST.DEFAULT_AVATAR_COUNT) + 1;
+    const avatarPrefix = `default-avatar`;
 
     return `${CONST.CLOUDFRONT_URL}/images/avatars/${avatarPrefix}_${accountIDHashBucket}.png`;
 }
@@ -135,7 +165,7 @@ function isDefaultAvatar(avatarSource?: AvatarSource): boolean {
  * @param accountID - the accountID of the user
  */
 function getAvatar(avatarSource: AvatarSource, accountID?: number): AvatarSource {
-    return isDefaultAvatar(avatarSource) ? getDefaultAvatar(accountID) : avatarSource;
+    return isDefaultAvatar(avatarSource) ? getDefaultAvatar(accountID, avatarSource as string) : avatarSource;
 }
 
 /**
@@ -146,7 +176,7 @@ function getAvatar(avatarSource: AvatarSource, accountID?: number): AvatarSource
  * @param accountID - the accountID of the user
  */
 function getAvatarUrl(avatarURL: string, accountID: number): string {
-    return isDefaultAvatar(avatarURL) ? getDefaultAvatarURL(accountID, true) : avatarURL;
+    return isDefaultAvatar(avatarURL) ? getDefaultAvatarURL(accountID) : avatarURL;
 }
 
 /**
@@ -184,13 +214,6 @@ function getSmallSizeAvatar(avatarSource: AvatarSource, accountID?: number): Ava
     return `${source.substring(0, lastPeriodIndex)}_128${source.substring(lastPeriodIndex)}`;
 }
 
-/**
- * Generate a random accountID base on searchValue.
- */
-function generateAccountID(searchValue: string): number {
-    return hashText(searchValue, 2 ** 32);
-}
-
 /**
  * Gets the secondary phone login number
  */