diff --git a/src/components/settings/SettingsPanel.tsx b/src/components/settings/SettingsPanel.tsx
index 9e4af71..edaa290 100644
--- a/src/components/settings/SettingsPanel.tsx
+++ b/src/components/settings/SettingsPanel.tsx
@@ -5,7 +5,7 @@ import toast from 'react-hot-toast';
 import { Card } from '@/components/ui';
 import { bcClient } from '@/services/bc/bcClient';
 import { useAuth, useProfilePhoto } from '@/services/auth';
-import { useCompanyStore } from '@/hooks';
+import { useCompanyStore, useSettingsStore } from '@/hooks';
 import {
   BuildingOffice2Icon,
   BuildingOfficeIcon,
@@ -33,6 +33,7 @@ export function SettingsPanel() {
   const { account, isAuthenticated } = useAuth();
   const { photoUrl } = useProfilePhoto(isAuthenticated);
   const { selectedCompany } = useCompanyStore();
+  const { requireTimesheetComments, updateSettings } = useSettingsStore();
   const [companyInfo, setCompanyInfo] = useState<CompanyInfo | null>(null);
   const [isLoading, setIsLoading] = useState(true);
   const [error, setError] = useState<string | null>(null);
@@ -236,7 +237,30 @@ export function SettingsPanel() {
               <p className="text-dark-400 text-sm">Get reminded to fill in your timesheet</p>
             </div>
             <label className="relative inline-flex cursor-pointer items-center">
-              <input type="checkbox" defaultChecked className="peer sr-only" />
+              <input
+                type="checkbox"
+                defaultChecked
+                aria-label="Timesheet Reminders"
+                className="peer sr-only"
+              />
+              <div className="peer bg-dark-600 peer-checked:bg-thyme-600 peer-focus:ring-thyme-500 h-6 w-11 rounded-full peer-focus:ring-2 peer-focus:outline-none after:absolute after:top-[2px] after:left-[2px] after:h-5 after:w-5 after:rounded-full after:bg-white after:transition-all after:content-[''] peer-checked:after:translate-x-full"></div>
+            </label>
+          </div>
+          <div className="flex items-center justify-between">
+            <div>
+              <p className="text-dark-100">Require Comments on Time Entries</p>
+              <p className="text-dark-400 text-sm">
+                Enforce adding notes/comments when logging time
+              </p>
+            </div>
+            <label className="relative inline-flex cursor-pointer items-center">
+              <input
+                type="checkbox"
+                checked={requireTimesheetComments}
+                onChange={(e) => updateSettings({ requireTimesheetComments: e.target.checked })}
+                aria-label="Require Comments on Time Entries"
+                className="peer sr-only"
+              />
               <div className="peer bg-dark-600 peer-checked:bg-thyme-600 peer-focus:ring-thyme-500 h-6 w-11 rounded-full peer-focus:ring-2 peer-focus:outline-none after:absolute after:top-[2px] after:left-[2px] after:h-5 after:w-5 after:rounded-full after:bg-white after:transition-all after:content-[''] peer-checked:after:translate-x-full"></div>
             </label>
           </div>
diff --git a/src/components/timesheet/TimeEntryModal.tsx b/src/components/timesheet/TimeEntryModal.tsx
index 3134db2..a57e638 100644
--- a/src/components/timesheet/TimeEntryModal.tsx
+++ b/src/components/timesheet/TimeEntryModal.tsx
@@ -4,7 +4,7 @@ import { useState, useEffect, useMemo, useCallback } from 'react';
 import toast from 'react-hot-toast';
 import { TrashIcon, ExclamationTriangleIcon } from '@heroicons/react/24/outline';
 import { Modal, Button, Input, Select } from '@/components/ui';
-import { useTimeEntriesStore, useProjectsStore } from '@/hooks';
+import { useTimeEntriesStore, useProjectsStore, useSettingsStore } from '@/hooks';
 import { useAuth } from '@/services/auth';
 import { bcClient } from '@/services/bc/bcClient';
 import type { TimeEntry, SelectOption } from '@/types';
@@ -26,6 +26,7 @@ export function TimeEntryModal({ isOpen, onClose, date, entry }: TimeEntryModalP
 
   const { addEntry, updateEntry, deleteEntry } = useTimeEntriesStore();
   const { projects, selectedProject, selectedTask, selectProject, selectTask } = useProjectsStore();
+  const { requireTimesheetComments } = useSettingsStore();
 
   const [customerId, setCustomerId] = useState('');
   const [projectId, setProjectId] = useState('');
@@ -193,6 +194,11 @@ export function TimeEntryModal({ isOpen, onClose, date, entry }: TimeEntryModalP
       return;
     }
 
+    if (requireTimesheetComments && !notes.trim()) {
+      toast.error('Notes are required. Please add a comment before saving.');
+      return;
+    }
+
     if (notes.length > MAX_NOTES_LENGTH) {
       toast.error(`Notes cannot exceed ${MAX_NOTES_LENGTH} characters.`);
       return;
@@ -354,7 +360,7 @@ export function TimeEntryModal({ isOpen, onClose, date, entry }: TimeEntryModalP
         {/* Notes */}
         <div>
           <label htmlFor="notes" className="text-dark-200 mb-1 block text-sm font-medium">
-            Notes (optional)
+            Notes ({requireTimesheetComments ? 'required' : 'optional'})
           </label>
           <textarea
             id="notes"
@@ -362,6 +368,7 @@ export function TimeEntryModal({ isOpen, onClose, date, entry }: TimeEntryModalP
             value={notes}
             onChange={(e) => setNotes(e.target.value)}
             maxLength={MAX_NOTES_LENGTH}
+            required={requireTimesheetComments}
             className={`border-dark-600 bg-dark-700 text-dark-100 placeholder:text-dark-400 focus:ring-thyme-500 flex w-full rounded-lg border px-3 py-2 text-sm focus:border-transparent focus:ring-2 focus:outline-none ${
               notes.length >= MAX_NOTES_LENGTH ? 'border-red-500' : ''
             }`}
diff --git a/src/components/timesheet/WeeklyTimesheet.tsx b/src/components/timesheet/WeeklyTimesheet.tsx
index 8da2c48..74dc103 100644
--- a/src/components/timesheet/WeeklyTimesheet.tsx
+++ b/src/components/timesheet/WeeklyTimesheet.tsx
@@ -13,7 +13,7 @@ import {
   UserCircleIcon,
   EnvelopeIcon,
 } from '@heroicons/react/24/outline';
-import { useTimeEntriesStore, useProjectsStore, useTeammateStore } from '@/hooks';
+import { useTimeEntriesStore, useProjectsStore, useTeammateStore, useSettingsStore } from '@/hooks';
 import { useAuth } from '@/services/auth';
 import { Button, Card, WeekNavigation, ExtensionPreviewWrapper } from '@/components/ui';
 import { TimeEntryCell } from './TimeEntryCell';
@@ -38,6 +38,7 @@ export function WeeklyTimesheet() {
   const userId = account?.localAccountId || '';
   const userEmail = account?.username || '';
   const { selectedTeammate } = useTeammateStore();
+  const { requireTimesheetComments } = useSettingsStore();
   const isViewingTeammate = selectedTeammate !== null;
 
   const searchParams = useSearchParams();
@@ -208,6 +209,17 @@ export function WeeklyTimesheet() {
 
   const handleSubmitTimesheet = async () => {
     if (!currentTimesheet) return;
+
+    if (requireTimesheetComments) {
+      const entriesMissingNotes = entries.filter((e) => !e.notes?.trim());
+      if (entriesMissingNotes.length > 0) {
+        toast.error(
+          `${entriesMissingNotes.length} ${entriesMissingNotes.length === 1 ? 'entry is' : 'entries are'} missing comments. Please add notes to all entries before submitting.`
+        );
+        return;
+      }
+    }
+
     setIsSubmitting(true);
     try {
       await submitTimesheet();
diff --git a/src/hooks/useSettingsStore.ts b/src/hooks/useSettingsStore.ts
index 93f93b9..a7609ce 100644
--- a/src/hooks/useSettingsStore.ts
+++ b/src/hooks/useSettingsStore.ts
@@ -12,6 +12,7 @@ const defaultSettings: UserSettings = {
   defaultTaskId: undefined,
   weeklyHoursTarget: 40,
   notificationsEnabled: true,
+  requireTimesheetComments: false,
   theme: 'system',
 };
 
diff --git a/src/types/index.ts b/src/types/index.ts
index ef38cd2..6be6cf6 100644
--- a/src/types/index.ts
+++ b/src/types/index.ts
@@ -296,6 +296,7 @@ export interface UserSettings {
   defaultTaskId?: string;
   weeklyHoursTarget: number;
   notificationsEnabled: boolean;
+  requireTimesheetComments: boolean;
   theme: 'light' | 'dark' | 'system';
 }