diff --git a/app/javascript/dashboard/components/widgets/AttachmentsPreview.vue b/app/javascript/dashboard/components/widgets/AttachmentsPreview.vue
index 84d6c7277..2d5ded515 100644
--- a/app/javascript/dashboard/components/widgets/AttachmentsPreview.vue
+++ b/app/javascript/dashboard/components/widgets/AttachmentsPreview.vue
@@ -11,9 +11,7 @@
           class="image-thumb"
           :src="attachment.thumb"
         />
-        <span v-else class="attachment-thumb">
-          📄
-        </span>
+        <span v-else class="attachment-thumb"> 📄 </span>
       </div>
       <div class="file-name-wrap">
         <span class="item">
@@ -37,8 +35,7 @@
   </div>
 </template>
 <script>
-import { formatBytes } from 'dashboard/helper/files';
-
+import { formatBytes } from 'shared/helpers/FileHelper';
 export default {
   props: {
     attachments: {
diff --git a/app/javascript/dashboard/components/widgets/conversation/ReplyBox.vue b/app/javascript/dashboard/components/widgets/conversation/ReplyBox.vue
index 30a37d5b8..0aeb9edcd 100644
--- a/app/javascript/dashboard/components/widgets/conversation/ReplyBox.vue
+++ b/app/javascript/dashboard/components/widgets/conversation/ReplyBox.vue
@@ -72,6 +72,7 @@
 <script>
 import { mapGetters } from 'vuex';
 import { mixin as clickaway } from 'vue-clickaway';
+import alertMixin from 'shared/mixins/alertMixin';
 
 import EmojiInput from 'shared/components/emoji/EmojiInput';
 import CannedResponse from './CannedResponse';
@@ -81,6 +82,9 @@ import ReplyTopPanel from 'dashboard/components/widgets/WootWriter/ReplyTopPanel
 import ReplyBottomPanel from 'dashboard/components/widgets/WootWriter/ReplyBottomPanel';
 import { REPLY_EDITOR_MODES } from 'dashboard/components/widgets/WootWriter/constants';
 import WootMessageEditor from 'dashboard/components/widgets/WootWriter/Editor';
+import { checkFileSizeLimit } from 'shared/helpers/FileHelper';
+import { MAXIMUM_FILE_UPLOAD_SIZE } from 'shared/constants/messages';
+
 import {
   isEscape,
   isEnter,
@@ -100,7 +104,7 @@ export default {
     ReplyBottomPanel,
     WootMessageEditor,
   },
-  mixins: [clickaway, inboxMixin, uiSettingsMixin],
+  mixins: [clickaway, inboxMixin, uiSettingsMixin, alertMixin],
   props: {
     inReplyTo: {
       type: [String, Number],
@@ -351,21 +355,28 @@ export default {
       }
     },
     onFileUpload(file) {
-      this.attachedFiles = [];
       if (!file) {
         return;
       }
-      const reader = new FileReader();
-      reader.readAsDataURL(file.file);
-
-      reader.onloadend = () => {
-        this.attachedFiles.push({
-          currentChatId: this.currentChat.id,
-          resource: file,
-          isPrivate: this.isPrivate,
-          thumb: reader.result,
-        });
-      };
+      if (checkFileSizeLimit(file, MAXIMUM_FILE_UPLOAD_SIZE)) {
+        this.attachedFiles = [];
+        const reader = new FileReader();
+        reader.readAsDataURL(file.file);
+        reader.onloadend = () => {
+          this.attachedFiles.push({
+            currentChatId: this.currentChat.id,
+            resource: file,
+            isPrivate: this.isPrivate,
+            thumb: reader.result,
+          });
+        };
+      } else {
+        this.showAlert(
+          this.$t('CONVERSATION.FILE_SIZE_LIMIT', {
+            MAXIMUM_FILE_UPLOAD_SIZE,
+          })
+        );
+      }
     },
     removeAttachment(itemIndex) {
       this.attachedFiles = this.attachedFiles.filter(
diff --git a/app/javascript/dashboard/helper/files.js b/app/javascript/dashboard/helper/files.js
deleted file mode 100644
index 4f7559304..000000000
--- a/app/javascript/dashboard/helper/files.js
+++ /dev/null
@@ -1,11 +0,0 @@
-export const formatBytes = (bytes, decimals = 2) => {
-  if (bytes === 0) return '0 Bytes';
-
-  const k = 1024;
-  const dm = decimals < 0 ? 0 : decimals;
-  const sizes = ['Bytes', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'];
-
-  const i = Math.floor(Math.log(bytes) / Math.log(k));
-
-  return parseFloat((bytes / Math.pow(k, i)).toFixed(dm)) + ' ' + sizes[i];
-};
diff --git a/app/javascript/dashboard/helper/specs/files.spec.js b/app/javascript/dashboard/helper/specs/files.spec.js
deleted file mode 100644
index 3b2c86bcd..000000000
--- a/app/javascript/dashboard/helper/specs/files.spec.js
+++ /dev/null
@@ -1,18 +0,0 @@
-import { formatBytes } from '../files';
-
-describe('#File Helpers', () => {
-  describe('formatBytes', () => {
-    it('should return zero bytes if 0 is passed', () => {
-      expect(formatBytes(0)).toBe('0 Bytes');
-    });
-    it('should return in bytes if 1000 is passed', () => {
-      expect(formatBytes(1000)).toBe('1000 Bytes');
-    });
-    it('should return in KB if 100000 is passed', () => {
-      expect(formatBytes(10000)).toBe('9.77 KB');
-    });
-    it('should return in MB if 10000000 is passed', () => {
-      expect(formatBytes(10000000)).toBe('9.54 MB');
-    });
-  });
-});
diff --git a/app/javascript/dashboard/i18n/locale/en/conversation.json b/app/javascript/dashboard/i18n/locale/en/conversation.json
index 68e4142fa..b13404e91 100644
--- a/app/javascript/dashboard/i18n/locale/en/conversation.json
+++ b/app/javascript/dashboard/i18n/locale/en/conversation.json
@@ -58,6 +58,7 @@
     "CHANGE_STATUS": "Conversation status changed",
     "CHANGE_AGENT": "Conversation Assignee changed",
     "CHANGE_TEAM": "Conversation team changed",
+    "FILE_SIZE_LIMIT": "File exceeds the {MAXIMUM_FILE_UPLOAD_SIZE} attachment limit",
     "SENT_BY": "Sent by:",
     "ASSIGNMENT": {
       "SELECT_AGENT": "Select Agent",
diff --git a/app/javascript/shared/constants/busEvents.js b/app/javascript/shared/constants/busEvents.js
index 6c7a4e24e..45992a63d 100644
--- a/app/javascript/shared/constants/busEvents.js
+++ b/app/javascript/shared/constants/busEvents.js
@@ -1,4 +1,5 @@
 export const BUS_EVENTS = {
   SET_REFERRER_HOST: 'SET_REFERRER_HOST',
   SET_TWEET_REPLY: 'SET_TWEET_REPLY',
+  ATTACHMENT_SIZE_CHECK_ERROR: 'ATTACHMENT_SIZE_CHECK_ERROR',
 };
diff --git a/app/javascript/shared/constants/messages.js b/app/javascript/shared/constants/messages.js
index 5f6ab6a5d..75eda5352 100644
--- a/app/javascript/shared/constants/messages.js
+++ b/app/javascript/shared/constants/messages.js
@@ -10,3 +10,5 @@ export const MESSAGE_TYPE = {
   ACTIVITY: 2,
   TEMPLATE: 3,
 };
+// Size in mega bytes
+export const MAXIMUM_FILE_UPLOAD_SIZE = 40;
diff --git a/app/javascript/shared/helpers/FileHelper.js b/app/javascript/shared/helpers/FileHelper.js
new file mode 100644
index 000000000..a784b2ba2
--- /dev/null
+++ b/app/javascript/shared/helpers/FileHelper.js
@@ -0,0 +1,25 @@
+export const formatBytes = (bytes, decimals = 2) => {
+  if (bytes === 0) return '0 Bytes';
+
+  const k = 1024;
+  const dm = decimals < 0 ? 0 : decimals;
+  const sizes = ['Bytes', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'];
+
+  const i = Math.floor(Math.log(bytes) / Math.log(k));
+
+  return parseFloat((bytes / Math.pow(k, i)).toFixed(dm)) + ' ' + sizes[i];
+};
+
+export const fileSizeInMegaBytes = bytes => {
+  if (bytes === 0) {
+    return 0;
+  }
+  const sizeInMB = (bytes / (1024 * 1024)).toFixed(2);
+  return sizeInMB;
+};
+
+export const checkFileSizeLimit = (file, maximumUploadLimit) => {
+  const fileSize = file?.file?.size;
+  const fileSizeInMB = fileSizeInMegaBytes(fileSize);
+  return fileSizeInMB <= maximumUploadLimit;
+};
diff --git a/app/javascript/shared/helpers/specs/FileHelper.spec.js b/app/javascript/shared/helpers/specs/FileHelper.spec.js
new file mode 100644
index 000000000..a0d1ac52f
--- /dev/null
+++ b/app/javascript/shared/helpers/specs/FileHelper.spec.js
@@ -0,0 +1,38 @@
+import {
+  formatBytes,
+  fileSizeInMegaBytes,
+  checkFileSizeLimit,
+} from '../FileHelper';
+
+describe('#File Helpers', () => {
+  describe('formatBytes', () => {
+    it('should return zero bytes if 0 is passed', () => {
+      expect(formatBytes(0)).toBe('0 Bytes');
+    });
+    it('should return in bytes if 1000 is passed', () => {
+      expect(formatBytes(1000)).toBe('1000 Bytes');
+    });
+    it('should return in KB if 100000 is passed', () => {
+      expect(formatBytes(10000)).toBe('9.77 KB');
+    });
+    it('should return in MB if 10000000 is passed', () => {
+      expect(formatBytes(10000000)).toBe('9.54 MB');
+    });
+  });
+  describe('fileSizeInMegaBytes', () => {
+    it('should return zero if 0 is passed', () => {
+      expect(fileSizeInMegaBytes(0)).toBe(0);
+    });
+    it('should return 19.07 if 20000000 is passed', () => {
+      expect(fileSizeInMegaBytes(20000000)).toBe('19.07');
+    });
+  });
+  describe('checkFileSizeLimit', () => {
+    it('should return false if file with size 62208194 and file size limit 40 are passed', () => {
+      expect(checkFileSizeLimit({ file: { size: 62208194 } }, 40)).toBe(false);
+    });
+    it('should return true if file with size 62208194 and file size limit 40 are passed', () => {
+      expect(checkFileSizeLimit({ file: { size: 199154 } }, 40)).toBe(true);
+    });
+  });
+});
diff --git a/app/javascript/widget/components/ChatAttachment.vue b/app/javascript/widget/components/ChatAttachment.vue
index 48f0463ef..4c872939c 100755
--- a/app/javascript/widget/components/ChatAttachment.vue
+++ b/app/javascript/widget/components/ChatAttachment.vue
@@ -4,7 +4,7 @@
     accept="image/*, application/pdf, audio/mpeg, video/mp4, audio/ogg, text/csv"
     @input-file="onFileUpload"
   >
-    <span class="attachment-button ">
+    <span class="attachment-button">
       <i v-if="!isUploading.image" class="ion-android-attach" />
       <spinner v-if="isUploading" size="small" />
     </span>
@@ -14,6 +14,9 @@
 <script>
 import FileUpload from 'vue-upload-component';
 import Spinner from 'shared/components/Spinner.vue';
+import { checkFileSizeLimit } from 'shared/helpers/FileHelper';
+import { MAXIMUM_FILE_UPLOAD_SIZE } from 'shared/constants/messages';
+import { BUS_EVENTS } from 'shared/constants/busEvents';
 
 export default {
   components: { FileUpload, Spinner },
@@ -31,14 +34,21 @@ export default {
       return fileType.includes('image') ? 'image' : 'file';
     },
     async onFileUpload(file) {
+      if (!file) {
+        return;
+      }
       this.isUploading = true;
       try {
-        const thumbUrl = window.URL.createObjectURL(file.file);
-        await this.onAttach({
-          fileType: this.getFileType(file.type),
-          file: file.file,
-          thumbUrl,
-        });
+        if (checkFileSizeLimit(file, MAXIMUM_FILE_UPLOAD_SIZE)) {
+          const thumbUrl = window.URL.createObjectURL(file.file);
+          await this.onAttach({
+            fileType: this.getFileType(file.type),
+            file: file.file,
+            thumbUrl,
+          });
+        } else {
+          window.bus.$emit(BUS_EVENTS.ATTACHMENT_SIZE_CHECK_ERROR);
+        }
       } catch (error) {
         // Error
       }
diff --git a/app/javascript/widget/i18n/locale/en.json b/app/javascript/widget/i18n/locale/en.json
index 33a27d18b..776ad30a0 100644
--- a/app/javascript/widget/i18n/locale/en.json
+++ b/app/javascript/widget/i18n/locale/en.json
@@ -48,5 +48,6 @@
         "ERROR": "Message too short"
       }
     }
-  }
+  },
+  "FILE_SIZE_LIMIT": "File exceeds the {MAXIMUM_FILE_UPLOAD_SIZE} attachment limit"
 }
diff --git a/app/javascript/widget/views/Home.vue b/app/javascript/widget/views/Home.vue
index 32f784ec7..3d77f33b5 100755
--- a/app/javascript/widget/views/Home.vue
+++ b/app/javascript/widget/views/Home.vue
@@ -34,6 +34,15 @@
         />
       </transition>
     </div>
+    <div v-if="showAttachmentError" class="banner">
+      <span>
+        {{
+          $t('FILE_SIZE_LIMIT', {
+            MAXIMUM_FILE_UPLOAD_SIZE: fileUploadSizeLimit,
+          })
+        }}
+      </span>
+    </div>
     <div class="flex flex-1 overflow-auto">
       <conversation-wrap
         v-if="currentView === 'messageView'"
@@ -80,6 +89,8 @@ import configMixin from '../mixins/configMixin';
 import TeamAvailability from 'widget/components/TeamAvailability';
 import Spinner from 'shared/components/Spinner.vue';
 import { mapGetters } from 'vuex';
+import { MAXIMUM_FILE_UPLOAD_SIZE } from 'shared/constants/messages';
+import { BUS_EVENTS } from 'shared/constants/busEvents';
 import PreChatForm from '../components/PreChat/Form';
 export default {
   name: 'Home',
@@ -105,7 +116,7 @@ export default {
     },
   },
   data() {
-    return { isOnCollapsedView: false };
+    return { isOnCollapsedView: false, showAttachmentError: false };
   },
   computed: {
     ...mapGetters({
@@ -132,6 +143,9 @@ export default {
     isOpen() {
       return this.conversationAttributes.status === 'open';
     },
+    fileUploadSizeLimit() {
+      return MAXIMUM_FILE_UPLOAD_SIZE;
+    },
     showInputTextArea() {
       if (this.hideInputForBotConversations) {
         if (this.isOpen) {
@@ -154,6 +168,14 @@ export default {
       );
     },
   },
+  mounted() {
+    bus.$on(BUS_EVENTS.ATTACHMENT_SIZE_CHECK_ERROR, () => {
+      this.showAttachmentError = true;
+      setTimeout(() => {
+        this.showAttachmentError = false;
+      }, 3000);
+    });
+  },
   methods: {
     startConversation() {
       this.isOnCollapsedView = !this.isOnCollapsedView;
@@ -221,5 +243,13 @@ export default {
   .input-wrap {
     padding: 0 $space-normal;
   }
+  .banner {
+    background: $color-error;
+    color: $color-white;
+    font-size: $font-size-default;
+    font-weight: $font-weight-bold;
+    padding: $space-slab;
+    text-align: center;
+  }
 }
 </style>