diff --git a/src/libs/UserUtils.js b/src/libs/UserUtils.ts
similarity index 63%
rename from src/libs/UserUtils.js
rename to src/libs/UserUtils.ts
index 2d5930b0dfd8..751ca5b69609 100644
--- a/src/libs/UserUtils.js
+++ b/src/libs/UserUtils.ts
@@ -1,9 +1,14 @@
-import _ from 'underscore';
-import lodashGet from 'lodash/get';
+import {SvgProps} from 'react-native-svg';
+import {ValueOf} from 'type-fest';
 import CONST from '../CONST';
 import hashCode from './hashCode';
-import * as Expensicons from '../components/Icon/Expensicons';
+import {ConciergeAvatar, FallbackAvatar} from '../components/Icon/Expensicons';
 import * as defaultAvatars from '../components/Icon/DefaultAvatars';
+import Login from '../types/onyx/Login';
+
+type AvatarRange = 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24;
+
+type LoginListIndicator = ValueOf<typeof CONST.BRICK_ROAD_INDICATOR_STATUS> | '';
 
 /**
  * Searches through given loginList for any contact method / login with an error.
@@ -25,36 +30,26 @@ import * as defaultAvatars from '../components/Icon/DefaultAvatars';
  *          }
  *      }
  * }}
- *
- * @param {Object} loginList
- * @param {Object} loginList.errorFields
- * @returns {Boolean}
  */
-function hasLoginListError(loginList) {
-    return _.some(loginList, (login) => _.some(lodashGet(login, 'errorFields', {}), (field) => !_.isEmpty(field)));
+function hasLoginListError(loginList: Login): boolean {
+    const errorFields = loginList?.errorFields ?? {};
+    return Object.values(errorFields).some((field) => Object.keys(field ?? {}).length > 0);
 }
 
 /**
  * Searches through given loginList for any contact method / login that requires
  * an Info brick road status indicator. Currently this only applies if the user
  * has an unvalidated contact method.
- *
- * @param {Object} loginList
- * @param {String} loginList.validatedDate
- * @returns {Boolean}
  */
-function hasLoginListInfo(loginList) {
-    return _.some(loginList, (login) => _.isEmpty(login.validatedDate));
+function hasLoginListInfo(loginList: Login): boolean {
+    return !loginList.validatedDate;
 }
 
 /**
  * Gets the appropriate brick road indicator status for a given loginList.
  * Error status is higher priority, so we check for that first.
- *
- * @param {Object} loginList
- * @returns {String}
  */
-function getLoginListBrickRoadIndicator(loginList) {
+function getLoginListBrickRoadIndicator(loginList: Login): LoginListIndicator {
     if (hasLoginListError(loginList)) {
         return CONST.BRICK_ROAD_INDICATOR_STATUS.ERROR;
     }
@@ -66,42 +61,35 @@ function getLoginListBrickRoadIndicator(loginList) {
 
 /**
  * Hashes provided string and returns a value between [0, range)
- * @param {String} text
- * @param {Number} range
- * @returns {Number}
  */
-function hashText(text, range) {
+function hashText(text: string, range: number): number {
     return Math.abs(hashCode(text.toLowerCase())) % range;
 }
 
 /**
  * Helper method to return the default avatar associated with the given accountID
- * @param {Number} [accountID]
- * @returns {String}
+ * @param [accountID]
+ * @returns
  */
-function getDefaultAvatar(accountID = -1) {
+function getDefaultAvatar(accountID = -1): React.FC<SvgProps> {
     if (accountID <= 0) {
-        return Expensicons.FallbackAvatar;
+        return FallbackAvatar;
     }
     if (Number(accountID) === CONST.ACCOUNT_ID.CONCIERGE) {
-        return Expensicons.ConciergeAvatar;
+        return ConciergeAvatar;
     }
 
     // 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;
+    const accountIDHashBucket = ((accountID % CONST.DEFAULT_AVATAR_COUNT) + 1) as AvatarRange;
 
     return defaultAvatars[`Avatar${accountIDHashBucket}`];
 }
 
 /**
  * Helper method to return default avatar URL associated with login
- *
- * @param {Number} [accountID]
- * @param {Boolean} [isNewDot]
- * @returns {String}
  */
-function getDefaultAvatarURL(accountID = '', isNewDot = false) {
+function getDefaultAvatarURL(accountID: string | number = '', isNewDot = false): string {
     if (Number(accountID) === CONST.ACCOUNT_ID.CONCIERGE) {
         return CONST.CONCIERGE_ICON_URL;
     }
@@ -115,26 +103,25 @@ function getDefaultAvatarURL(accountID = '', isNewDot = false) {
 
 /**
  * Given a user's avatar path, returns true if user doesn't have an avatar or if URL points to a default avatar
- * @param {String} [avatarURL] - the avatar source from user's personalDetails
- * @returns {Boolean}
+ * @param [avatarURL] - the avatar source from user's personalDetails
  */
-function isDefaultAvatar(avatarURL) {
-    if (
-        _.isString(avatarURL) &&
-        (avatarURL.includes('images/avatars/avatar_') || avatarURL.includes('images/avatars/default-avatar_') || avatarURL.includes('images/avatars/user/default'))
-    ) {
-        return true;
-    }
-
-    // We use a hardcoded "default" Concierge avatar
-    if (_.isString(avatarURL) && (avatarURL === CONST.CONCIERGE_ICON_URL_2021 || avatarURL === CONST.CONCIERGE_ICON_URL)) {
-        return true;
+function isDefaultAvatar(avatarURL?: string): boolean {
+    if (typeof avatarURL === 'string') {
+        if (avatarURL.includes('images/avatars/avatar_') || avatarURL.includes('images/avatars/default-avatar_') || avatarURL.includes('images/avatars/user/default')) {
+            return true;
+        }
+
+        // We use a hardcoded "default" Concierge avatar
+        if (avatarURL === CONST.CONCIERGE_ICON_URL_2021 || avatarURL === CONST.CONCIERGE_ICON_URL) {
+            return true;
+        }
     }
 
     if (!avatarURL) {
         // If null URL, we should also use a default avatar
         return true;
     }
+
     return false;
 }
 
@@ -142,11 +129,10 @@ function isDefaultAvatar(avatarURL) {
  * Provided a source URL, if source is a default avatar, return the associated SVG.
  * Otherwise, return the URL pointing to a user-uploaded avatar.
  *
- * @param {String} avatarURL - the avatar source from user's personalDetails
- * @param {Number} accountID - the accountID of the user
- * @returns {String|Function}
+ * @param avatarURL - the avatar source from user's personalDetails
+ * @param accountID - the accountID of the user
  */
-function getAvatar(avatarURL, accountID) {
+function getAvatar(avatarURL: string, accountID: number): React.FC<SvgProps> | string {
     return isDefaultAvatar(avatarURL) ? getDefaultAvatar(accountID) : avatarURL;
 }
 
@@ -154,25 +140,20 @@ function getAvatar(avatarURL, accountID) {
  * Provided an avatar URL, if avatar is a default avatar, return NewDot default avatar URL.
  * Otherwise, return the URL pointing to a user-uploaded avatar.
  *
- * @param {String} avatarURL - the avatar source from user's personalDetails
- * @param {Number} accountID - the accountID of the user
- * @returns {String}
+ * @param avatarURL - the avatar source from user's personalDetails
+ * @param accountID - the accountID of the user
  */
-function getAvatarUrl(avatarURL, accountID) {
+function getAvatarUrl(avatarURL: string, accountID: number): string {
     return isDefaultAvatar(avatarURL) ? getDefaultAvatarURL(accountID, true) : avatarURL;
 }
 
 /**
  * Avatars uploaded by users will have a _128 appended so that the asset server returns a small version.
  * This removes that part of the URL so the full version of the image can load.
- *
- * @param {String} [avatarURL]
- * @param {Number} [accountID]
- * @returns {String|Function}
  */
-function getFullSizeAvatar(avatarURL, accountID) {
+function getFullSizeAvatar(avatarURL: string, accountID: number): React.FC<SvgProps> | string {
     const source = getAvatar(avatarURL, accountID);
-    if (!_.isString(source)) {
+    if (typeof source !== 'string') {
         return source;
     }
     return source.replace('_128', '');
@@ -181,14 +162,10 @@ function getFullSizeAvatar(avatarURL, accountID) {
 /**
  * Small sized avatars end with _128.<file-type>. This adds the _128 at the end of the
  * source URL (before the file type) if it doesn't exist there already.
- *
- * @param {String} avatarURL
- * @param {Number} accountID
- * @returns {String|Function}
  */
-function getSmallSizeAvatar(avatarURL, accountID) {
+function getSmallSizeAvatar(avatarURL: string, accountID: number): React.FC<SvgProps> | string {
     const source = getAvatar(avatarURL, accountID);
-    if (!_.isString(source)) {
+    if (typeof source !== 'string') {
         return source;
     }
 
@@ -207,10 +184,8 @@ function getSmallSizeAvatar(avatarURL, accountID) {
 
 /**
  * Generate a random accountID base on searchValue.
- * @param {String} searchValue
- * @returns {Number}
  */
-function generateAccountID(searchValue) {
+function generateAccountID(searchValue: string): number {
     return hashText(searchValue, 2 ** 32);
 }