diff --git a/packages/client/src/methods/messages/find-in-update.ts b/packages/client/src/methods/messages/find-in-update.ts
index dbaa751e..389d4f8f 100644
--- a/packages/client/src/methods/messages/find-in-update.ts
+++ b/packages/client/src/methods/messages/find-in-update.ts
@@ -1,6 +1,7 @@
 import { TelegramClient } from '../../client'
 import { tl } from '@mtcute/tl'
 import { Message, MtCuteTypeAssertionError } from '../../types'
+import { createUsersChatsIndex } from '../../utils/peer-utils'
 
 /** @internal */
 export function _findMessageInUpdate(
@@ -20,10 +21,7 @@ export function _findMessageInUpdate(
             u._ === 'updateNewChannelMessage' ||
             u._ === 'updateNewScheduledMessage'
         ) {
-            const users: Record<number, tl.TypeUser> = {}
-            const chats: Record<number, tl.TypeChat> = {}
-            res.users.forEach((e) => (users[e.id] = e))
-            res.chats.forEach((e) => (chats[e.id] = e))
+            const { users, chats } = createUsersChatsIndex(res)
 
             return new Message(
                 this,
diff --git a/packages/client/src/methods/messages/get-messages.ts b/packages/client/src/methods/messages/get-messages.ts
index 66d9e152..9124ec6e 100644
--- a/packages/client/src/methods/messages/get-messages.ts
+++ b/packages/client/src/methods/messages/get-messages.ts
@@ -1,6 +1,6 @@
 import { TelegramClient } from '../../client'
 import { MaybeArray } from '@mtcute/core'
-import { normalizeToInputChannel } from '../../utils/peer-utils'
+import { createUsersChatsIndex, normalizeToInputChannel } from '../../utils/peer-utils'
 import { tl } from '@mtcute/tl'
 import { Message, InputPeerLike, MtCuteTypeAssertionError } from '../../types'
 
@@ -81,10 +81,7 @@ export async function getMessages(
             res._
         )
 
-    const users: Record<number, tl.TypeUser> = {}
-    const chats: Record<number, tl.TypeChat> = {}
-    res.users.forEach((e) => (users[e.id] = e))
-    res.chats.forEach((e) => (chats[e.id] = e))
+    const { users, chats } = createUsersChatsIndex(res)
 
     const ret = res.messages.map((msg) => new Message(this, msg, users, chats))
 
diff --git a/packages/client/src/methods/updates/handle-update.ts b/packages/client/src/methods/updates/handle-update.ts
index 1ad5cf5e..138323e9 100644
--- a/packages/client/src/methods/updates/handle-update.ts
+++ b/packages/client/src/methods/updates/handle-update.ts
@@ -2,7 +2,7 @@ import { tl } from '@mtcute/tl'
 import { TelegramClient } from '../../client'
 import { ChannelPrivateError } from '@mtcute/tl/errors'
 import { MAX_CHANNEL_ID } from '@mtcute/core'
-import { normalizeToInputChannel } from '../../utils/peer-utils'
+import { createUsersChatsIndex, normalizeToInputChannel } from '../../utils/peer-utils'
 import { extractChannelIdFromUpdate } from '../../utils/misc-utils'
 
 const debug = require('debug')('mtcute:upds')
@@ -21,10 +21,7 @@ export function _handleUpdate(
         if (update._ === 'updates' || update._ === 'updatesCombined') {
             const isMin = await this._cachePeersFrom(update)
 
-            const users: Record<number, tl.TypeUser> = {}
-            const chats: Record<number, tl.TypeChat> = {}
-            update.users.forEach((u) => (users[u.id] = u))
-            update.chats.forEach((u) => (chats[u.id] = u))
+            const { users, chats } = createUsersChatsIndex(update)
 
             for (const upd of update.updates) {
                 if (upd._ === 'updateChannelTooLong') {
@@ -167,10 +164,7 @@ export function _handleUpdate(
 
             if (diff._ === 'updates.difference') {
                 if (diff.newMessages.length) {
-                    const users: Record<number, tl.TypeUser> = {}
-                    const chats: Record<number, tl.TypeChat> = {}
-                    diff.users.forEach((u) => (users[u.id] = u))
-                    diff.chats.forEach((u) => (chats[u.id] = u))
+                    const { users, chats } = createUsersChatsIndex(diff)
 
                     await this._dispatchUpdate(
                         {
diff --git a/packages/client/src/utils/peer-utils.ts b/packages/client/src/utils/peer-utils.ts
index e60450d2..2f715ceb 100644
--- a/packages/client/src/utils/peer-utils.ts
+++ b/packages/client/src/utils/peer-utils.ts
@@ -77,3 +77,15 @@ export function inputPeerToPeer(inp: tl.TypeInputPeer): tl.TypePeer {
 
     return inp as never
 }
+
+export function createUsersChatsIndex(obj: { users: tl.TypeUser[], chats: tl.TypeChat[] }): {
+    users: Record<number, tl.TypeUser>
+    chats: Record<number, tl.TypeChat>
+} {
+    const users: Record<number, tl.TypeUser> = {}
+    const chats: Record<number, tl.TypeChat> = {}
+    obj.users.forEach((e) => (users[e.id] = e))
+    obj.chats.forEach((e) => (chats[e.id] = e))
+
+    return { users, chats }
+}