diff --git a/tests/Feature/Admin/Finance/CashAccountTest.php b/tests/Feature/Admin/Finance/CashAccountTest.php
index 3214333..700952c 100644
--- a/tests/Feature/Admin/Finance/CashAccountTest.php
+++ b/tests/Feature/Admin/Finance/CashAccountTest.php
@@ -90,6 +90,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 50000,
         'description' => 'Deposit test',
+        'receipt_key' => 'cash-transaction/deposit-001.jpg',
     ]);
 
     $response
@@ -108,6 +109,7 @@
     $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 50000,
         'description' => 'Deposit test',
+        'receipt_key' => 'cash-transaction/deposit-001.jpg',
     ]);
 
     $this->assertDatabaseCount('cash_transactions', 1);
@@ -128,6 +130,7 @@
     $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 50000,
         'description' => 'Deposit test',
+        'receipt_key' => 'cash-transaction/deposit-001.jpg',
     ]);
 
     $this->assertDatabaseHas('cash_transactions', [
@@ -144,6 +147,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => '',
         'description' => 'Test',
+        'receipt_key' => 'cash-transaction/receipt.jpg',
     ]);
 
     $response->assertSessionHasErrors('amount');
@@ -158,6 +162,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 'abc',
         'description' => 'Test',
+        'receipt_key' => 'cash-transaction/receipt.jpg',
     ]);
 
     $response->assertSessionHasErrors('amount');
@@ -172,6 +177,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 0,
         'description' => 'Test',
+        'receipt_key' => 'cash-transaction/receipt.jpg',
     ]);
 
     $response->assertSessionHasErrors('amount');
@@ -186,6 +192,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 1,
         'description' => 'Minimum deposit',
+        'receipt_key' => 'cash-transaction/receipt.jpg',
     ]);
 
     $response->assertSessionHasNoErrors();
@@ -201,6 +208,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 50000,
         'description' => '',
+        'receipt_key' => 'cash-transaction/receipt.jpg',
     ]);
 
     $response->assertSessionHasErrors('description');
@@ -215,6 +223,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 50000,
         'description' => str_repeat('a', 101),
+        'receipt_key' => 'cash-transaction/receipt.jpg',
     ]);
 
     $response->assertSessionHasErrors('description');
@@ -229,6 +238,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 50000,
         'description' => str_repeat('a', 100),
+        'receipt_key' => 'cash-transaction/receipt.jpg',
     ]);
 
     $response->assertSessionHasNoErrors();
@@ -243,6 +253,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => '50.000',
         'description' => 'Formatted deposit',
+        'receipt_key' => 'cash-transaction/receipt.jpg',
     ]);
 
     $response->assertSessionHasNoErrors();
@@ -258,6 +269,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 1000000000,
         'description' => 'Large deposit',
+        'receipt_key' => 'cash-transaction/receipt.jpg',
     ]);
 
     $response->assertSessionHasNoErrors();
@@ -273,6 +285,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => -50000,
         'description' => 'Negative deposit',
+        'receipt_key' => 'cash-transaction/receipt.jpg',
     ]);
 
     $response->assertSessionHasErrors('amount');
@@ -287,16 +300,19 @@
     $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 100000,
         'description' => 'First deposit',
+        'receipt_key' => 'cash-transaction/receipt1.jpg',
     ]);
 
     $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 200000,
         'description' => 'Second deposit',
+        'receipt_key' => 'cash-transaction/receipt2.jpg',
     ]);
 
     $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 300000,
         'description' => 'Third deposit',
+        'receipt_key' => 'cash-transaction/receipt3.jpg',
     ]);
 
     expect(CashAccount::first()->balance)->toBe(600000);
@@ -312,6 +328,7 @@
     $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 50000,
         'description' => 'First deposit',
+        'receipt_key' => 'cash-transaction/receipt.jpg',
     ]);
 
     expect(CashAccount::first()->balance)->toBe(50000);
@@ -326,11 +343,56 @@
     $response = $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 50000,
         'description' => 'Deposit toast test',
+        'receipt_key' => 'cash-transaction/receipt.jpg',
     ]);
 
     $response->assertRedirect();
 });
 
+test('deposit receipt_key is required', function () {
+    $user = User::factory()->create();
+    $this->actingAs($user);
+
+    CashAccount::factory()->create(['balance' => 100000]);
+
+    $response = $this->post(route('admin.finance.cash-accounts.deposit'), [
+        'amount' => 50000,
+        'description' => 'Test',
+    ]);
+
+    $response->assertSessionHasErrors('receipt_key');
+});
+
+test('deposit receipt_key max length is 500', function () {
+    $user = User::factory()->create();
+    $this->actingAs($user);
+
+    CashAccount::factory()->create(['balance' => 100000]);
+
+    $response = $this->post(route('admin.finance.cash-accounts.deposit'), [
+        'amount' => 50000,
+        'description' => 'Test',
+        'receipt_key' => str_repeat('a', 501),
+    ]);
+
+    $response->assertSessionHasErrors('receipt_key');
+});
+
+test('deposit receipt_key exactly 500 characters is accepted', function () {
+    $user = User::factory()->create();
+    $this->actingAs($user);
+
+    CashAccount::factory()->create(['balance' => 0]);
+
+    $response = $this->post(route('admin.finance.cash-accounts.deposit'), [
+        'amount' => 50000,
+        'description' => 'Test',
+        'receipt_key' => str_repeat('a', 500),
+    ]);
+
+    $response->assertSessionHasNoErrors();
+});
+
 /*
 |--------------------------------------------------------------------------
 | WITHDRAWAL
@@ -346,6 +408,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 30000,
         'description' => 'Withdrawal test',
+        'receipt_key' => 'cash-transaction/withdrawal-001.jpg',
     ]);
 
     $response
@@ -364,6 +427,7 @@
     $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 30000,
         'description' => 'Withdrawal test',
+        'receipt_key' => 'cash-transaction/withdrawal-001.jpg',
     ]);
 
     $this->assertDatabaseCount('cash_transactions', 1);
@@ -384,6 +448,7 @@
     $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 30000,
         'description' => 'Withdrawal test',
+        'receipt_key' => 'cash-transaction/withdrawal-001.jpg',
     ]);
 
     $this->assertDatabaseHas('cash_transactions', [
@@ -400,6 +465,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 100000,
         'description' => 'Withdrawal test',
+        'receipt_key' => 'cash-transaction/withdrawal.jpg',
     ]);
 
     // Controller catches ValidationException and flashes toast error
@@ -416,6 +482,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 50000,
         'description' => 'Withdrawal exact balance',
+        'receipt_key' => 'cash-transaction/withdrawal.jpg',
     ]);
 
     $response->assertSessionHasNoErrors();
@@ -431,6 +498,7 @@
     $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 100000,
         'description' => 'Withdraw all',
+        'receipt_key' => 'cash-transaction/withdrawal.jpg',
     ]);
 
     expect(CashAccount::first()->balance)->toBe(0);
@@ -445,6 +513,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => '',
         'description' => 'Test',
+        'receipt_key' => 'cash-transaction/withdrawal.jpg',
     ]);
 
     $response->assertSessionHasErrors('amount');
@@ -459,6 +528,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 'abc',
         'description' => 'Test',
+        'receipt_key' => 'cash-transaction/withdrawal.jpg',
     ]);
 
     $response->assertSessionHasErrors('amount');
@@ -473,6 +543,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 0,
         'description' => 'Test',
+        'receipt_key' => 'cash-transaction/withdrawal.jpg',
     ]);
 
     $response->assertSessionHasErrors('amount');
@@ -487,6 +558,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 50000,
         'description' => '',
+        'receipt_key' => 'cash-transaction/withdrawal.jpg',
     ]);
 
     $response->assertSessionHasErrors('description');
@@ -501,6 +573,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 50000,
         'description' => str_repeat('a', 101),
+        'receipt_key' => 'cash-transaction/withdrawal.jpg',
     ]);
 
     $response->assertSessionHasErrors('description');
@@ -515,6 +588,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => '50.000',
         'description' => 'Formatted withdrawal',
+        'receipt_key' => 'cash-transaction/withdrawal.jpg',
     ]);
 
     $response->assertSessionHasNoErrors();
@@ -530,6 +604,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => -50000,
         'description' => 'Negative withdrawal',
+        'receipt_key' => 'cash-transaction/withdrawal.jpg',
     ]);
 
     $response->assertSessionHasErrors('amount');
@@ -544,16 +619,19 @@
     $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 100000,
         'description' => 'First withdrawal',
+        'receipt_key' => 'cash-transaction/withdrawal1.jpg',
     ]);
 
     $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 200000,
         'description' => 'Second withdrawal',
+        'receipt_key' => 'cash-transaction/withdrawal2.jpg',
     ]);
 
     $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 300000,
         'description' => 'Third withdrawal',
+        'receipt_key' => 'cash-transaction/withdrawal3.jpg',
     ]);
 
     expect(CashAccount::first()->balance)->toBe(400000);
@@ -569,11 +647,56 @@
     $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 100000,
         'description' => 'Should fail',
+        'receipt_key' => 'cash-transaction/withdrawal.jpg',
     ]);
 
     $this->assertDatabaseCount('cash_transactions', 0);
 });
 
+test('withdrawal receipt_key is required', function () {
+    $user = User::factory()->create();
+    $this->actingAs($user);
+
+    CashAccount::factory()->create(['balance' => 100000]);
+
+    $response = $this->post(route('admin.finance.cash-accounts.withdrawal'), [
+        'amount' => 50000,
+        'description' => 'Test',
+    ]);
+
+    $response->assertSessionHasErrors('receipt_key');
+});
+
+test('withdrawal receipt_key max length is 500', function () {
+    $user = User::factory()->create();
+    $this->actingAs($user);
+
+    CashAccount::factory()->create(['balance' => 100000]);
+
+    $response = $this->post(route('admin.finance.cash-accounts.withdrawal'), [
+        'amount' => 50000,
+        'description' => 'Test',
+        'receipt_key' => str_repeat('a', 501),
+    ]);
+
+    $response->assertSessionHasErrors('receipt_key');
+});
+
+test('withdrawal receipt_key exactly 500 characters is accepted', function () {
+    $user = User::factory()->create();
+    $this->actingAs($user);
+
+    CashAccount::factory()->create(['balance' => 100000]);
+
+    $response = $this->post(route('admin.finance.cash-accounts.withdrawal'), [
+        'amount' => 50000,
+        'description' => 'Test',
+        'receipt_key' => str_repeat('a', 500),
+    ]);
+
+    $response->assertSessionHasNoErrors();
+});
+
 /*
 |--------------------------------------------------------------------------
 | MIXED DEPOSIT AND WITHDRAWAL
@@ -589,24 +712,28 @@
     $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 500000,
         'description' => 'Initial deposit',
+        'receipt_key' => 'cash-transaction/deposit1.jpg',
     ]);
     expect(CashAccount::first()->balance)->toBe(500000);
 
     $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 200000,
         'description' => 'First withdrawal',
+        'receipt_key' => 'cash-transaction/withdrawal1.jpg',
     ]);
     expect(CashAccount::first()->balance)->toBe(300000);
 
     $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 100000,
         'description' => 'Second deposit',
+        'receipt_key' => 'cash-transaction/deposit2.jpg',
     ]);
     expect(CashAccount::first()->balance)->toBe(400000);
 
     $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 400000,
         'description' => 'Final withdrawal',
+        'receipt_key' => 'cash-transaction/withdrawal2.jpg',
     ]);
     expect(CashAccount::first()->balance)->toBe(0);
 
@@ -622,11 +749,13 @@
     $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 100000,
         'description' => 'Deposit',
+        'receipt_key' => 'cash-transaction/deposit.jpg',
     ]);
 
     $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 80000,
         'description' => 'Withdrawal',
+        'receipt_key' => 'cash-transaction/withdrawal.jpg',
     ]);
 
     expect(CashAccount::first()->balance)->toBe(20000);
@@ -634,6 +763,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 30000,
         'description' => 'Should fail',
+        'receipt_key' => 'cash-transaction/withdrawal2.jpg',
     ]);
 
     $response->assertRedirect();
@@ -668,6 +798,7 @@
     $response = $this->put(route('admin.finance.cash-accounts.transactions.update', $transaction), [
         'amount' => 75000,
         'description' => 'Updated deposit',
+        'receipt_key' => 'cash-transaction/deposit-updated.jpg',
     ]);
 
     $response
@@ -702,6 +833,7 @@
     $response = $this->put(route('admin.finance.cash-accounts.transactions.update', $transaction), [
         'amount' => 20000,
         'description' => 'Updated withdrawal',
+        'receipt_key' => 'cash-transaction/withdrawal-updated.jpg',
     ]);
 
     $response->assertSessionHasNoErrors();
@@ -731,6 +863,7 @@
     $response = $this->put(route('admin.finance.cash-accounts.transactions.update', $transaction), [
         'amount' => 20000,
         'description' => 'Updated expense',
+        'receipt_key' => 'cash-transaction/expense-updated.jpg',
     ]);
 
     $response->assertRedirect();
@@ -755,6 +888,7 @@
     $response = $this->put(route('admin.finance.cash-accounts.transactions.update', $transaction), [
         'amount' => 20000,
         'description' => 'Updated transfer',
+        'receipt_key' => 'cash-transaction/transfer-updated.jpg',
     ]);
 
     $response->assertRedirect();
@@ -782,6 +916,7 @@
     $this->put(route('admin.finance.cash-accounts.transactions.update', $transaction), [
         'amount' => 80000,
         'description' => 'Increased',
+        'receipt_key' => 'cash-transaction/deposit-increased.jpg',
     ]);
 
     expect(CashAccount::first()->balance)->toBe(130000);
@@ -808,6 +943,7 @@
     $this->put(route('admin.finance.cash-accounts.transactions.update', $transaction), [
         'amount' => 20000,
         'description' => 'Decreased',
+        'receipt_key' => 'cash-transaction/deposit-decreased.jpg',
     ]);
 
     expect(CashAccount::first()->balance)->toBe(70000);
@@ -834,6 +970,7 @@
     $this->put(route('admin.finance.cash-accounts.transactions.update', $transaction), [
         'amount' => 50000,
         'description' => 'Increased withdrawal',
+        'receipt_key' => 'cash-transaction/withdrawal-increased.jpg',
     ]);
 
     expect(CashAccount::first()->balance)->toBe(80000);
@@ -860,6 +997,7 @@
     $this->put(route('admin.finance.cash-accounts.transactions.update', $transaction), [
         'amount' => 10000,
         'description' => 'Decreased withdrawal',
+        'receipt_key' => 'cash-transaction/withdrawal-decreased.jpg',
     ]);
 
     expect(CashAccount::first()->balance)->toBe(120000);
@@ -883,6 +1021,7 @@
     $response = $this->put(route('admin.finance.cash-accounts.transactions.update', $transaction), [
         'amount' => 0,
         'description' => 'Zero amount',
+        'receipt_key' => 'cash-transaction/deposit.jpg',
     ]);
 
     $response->assertSessionHasErrors('amount');
@@ -910,12 +1049,36 @@
     $response = $this->put(route('admin.finance.cash-accounts.transactions.update', $transaction), [
         'amount' => '75.000',
         'description' => 'Formatted amount',
+        'receipt_key' => 'cash-transaction/deposit.jpg',
     ]);
 
     $response->assertSessionHasNoErrors();
     expect(CashAccount::first()->balance)->toBe(125000);
 });
 
+test('transaction update requires receipt_key', function () {
+    $user = User::factory()->create();
+    $this->actingAs($user);
+
+    $cashAccount = CashAccount::factory()->create(['balance' => 100000]);
+
+    $transaction = CashTransaction::factory()->create([
+        'cash_account_id' => $cashAccount->id,
+        'created_by_id' => $user->id,
+        'type' => CashTransactionType::DEPOSIT,
+        'amount' => 50000,
+        'balance_after' => 100000,
+        'description' => 'Original',
+    ]);
+
+    $response = $this->put(route('admin.finance.cash-accounts.transactions.update', $transaction), [
+        'amount' => 75000,
+        'description' => 'Updated',
+    ]);
+
+    $response->assertSessionHasErrors('receipt_key');
+});
+
 /*
 |--------------------------------------------------------------------------
 | DELETE TRANSACTION
@@ -1024,12 +1187,14 @@
     $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 100000,
         'description' => 'Deposit 1',
+        'receipt_key' => 'cash-transaction/deposit1.jpg',
     ]);
     $t1 = CashTransaction::latest()->first();
 
     $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 50000,
         'description' => 'Deposit 2',
+        'receipt_key' => 'cash-transaction/deposit2.jpg',
     ]);
 
     expect(CashAccount::first()->balance)->toBe(150000);
@@ -1050,12 +1215,14 @@
     $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 50000,
         'description' => 'Withdrawal 1',
+        'receipt_key' => 'cash-transaction/withdrawal1.jpg',
     ]);
     $t1 = CashTransaction::latest()->first();
 
     $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 30000,
         'description' => 'Withdrawal 2',
+        'receipt_key' => 'cash-transaction/withdrawal2.jpg',
     ]);
 
     expect(CashAccount::first()->balance)->toBe(120000);
@@ -1076,6 +1243,7 @@
     $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 50000,
         'description' => 'Deposit',
+        'receipt_key' => 'cash-transaction/deposit.jpg',
     ]);
     $deposit = CashTransaction::latest()->first();
 
@@ -1083,6 +1251,7 @@
     $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 80000,
         'description' => 'Withdrawal',
+        'receipt_key' => 'cash-transaction/withdrawal.jpg',
     ]);
 
     expect(CashAccount::first()->balance)->toBe(20000);
@@ -1157,6 +1326,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 50000,
         'description' => 'Unauthorized',
+        'receipt_key' => 'cash-transaction/receipt.jpg',
     ]);
 
     $response->assertRedirect(route('login'));
@@ -1169,6 +1339,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 50000,
         'description' => 'Unauthorized',
+        'receipt_key' => 'cash-transaction/receipt.jpg',
     ]);
 
     $response->assertRedirect(route('login'));
@@ -1338,11 +1509,13 @@
     $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 500000,
         'description' => 'Modal usaha',
+        'receipt_key' => 'cash-transaction/deposit.jpg',
     ]);
 
     $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 100000,
         'description' => 'Belanja inventory',
+        'receipt_key' => 'cash-transaction/withdrawal.jpg',
     ]);
 
     expect(CashAccount::first()->balance)->toBe(400000);
@@ -1358,16 +1531,19 @@
     $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 200000,
         'description' => 'Penjualan pagi',
+        'receipt_key' => 'cash-transaction/deposit1.jpg',
     ]);
 
     $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 350000,
         'description' => 'Penjualan siang',
+        'receipt_key' => 'cash-transaction/deposit2.jpg',
     ]);
 
     $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 150000,
         'description' => 'Penjualan sore',
+        'receipt_key' => 'cash-transaction/deposit3.jpg',
     ]);
 
     expect(CashAccount::first()->balance)->toBe(700000);
@@ -1383,16 +1559,19 @@
     $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 50000,
         'description' => 'Bayar listrik',
+        'receipt_key' => 'cash-transaction/withdrawal1.jpg',
     ]);
 
     $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 30000,
         'description' => 'Bayar air',
+        'receipt_key' => 'cash-transaction/withdrawal2.jpg',
     ]);
 
     $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 200000,
         'description' => 'Gaji karyawan',
+        'receipt_key' => 'cash-transaction/withdrawal3.jpg',
     ]);
 
     expect(CashAccount::first()->balance)->toBe(720000);
@@ -1416,6 +1595,7 @@
     $response = $this->put(route('admin.finance.cash-accounts.transactions.update', $transaction), [
         'amount' => 100000,
         'description' => 'Penjualan produk A',
+        'receipt_key' => 'cash-transaction/deposit.jpg',
     ]);
 
     $response->assertSessionHasNoErrors();
@@ -1436,6 +1616,7 @@
     $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 100000,
         'description' => 'Wrong amount',
+        'receipt_key' => 'cash-transaction/deposit.jpg',
     ]);
     $wrongDeposit = CashTransaction::where('cash_account_id', $cashAccount->id)->first();
 
@@ -1449,6 +1630,7 @@
     $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 150000,
         'description' => 'Correct amount',
+        'receipt_key' => 'cash-transaction/deposit-correct.jpg',
     ]);
 
     expect(CashAccount::first()->balance)->toBe(150000);
@@ -1465,6 +1647,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 100000,
         'description' => 'Withdraw all',
+        'receipt_key' => 'cash-transaction/withdrawal.jpg',
     ]);
 
     $response->assertSessionHasNoErrors();
@@ -1480,6 +1663,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 100001,
         'description' => 'Over balance',
+        'receipt_key' => 'cash-transaction/withdrawal.jpg',
     ]);
 
     $response->assertRedirect();
@@ -1496,6 +1680,7 @@
         $this->post(route('admin.finance.cash-accounts.deposit'), [
             'amount' => 100000,
             'description' => "Deposit {$i}",
+            'receipt_key' => "cash-transaction/deposit{$i}.jpg",
         ]);
     }
 
@@ -1524,6 +1709,7 @@
     $response = $this->put(route('admin.finance.cash-accounts.transactions.update', $transaction), [
         'amount' => 20000,
         'description' => 'Reduced',
+        'receipt_key' => 'cash-transaction/withdrawal-reduced.jpg',
     ]);
 
     $response->assertSessionHasNoErrors();
@@ -1551,6 +1737,7 @@
     $response = $this->put(route('admin.finance.cash-accounts.transactions.update', $transaction), [
         'amount' => 60000,
         'description' => 'Increased',
+        'receipt_key' => 'cash-transaction/withdrawal-increased.jpg',
     ]);
 
     $response->assertSessionHasNoErrors();
@@ -1580,6 +1767,7 @@
     $response = $this->put(route('admin.finance.cash-accounts.transactions.update', $transaction), [
         'amount' => 200000,
         'description' => 'Way too much',
+        'receipt_key' => 'cash-transaction/withdrawal.jpg',
     ]);
 
     $response->assertRedirect();
@@ -1595,6 +1783,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 50000,
         'description' => 'Deposit dari PT. Maju Jaya & Co.',
+        'receipt_key' => 'cash-transaction/deposit.jpg',
     ]);
 
     $response->assertSessionHasNoErrors();
@@ -1612,6 +1801,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 50000,
         'description' => 'Pembayaran gaji karyawan',
+        'receipt_key' => 'cash-transaction/withdrawal.jpg',
     ]);
 
     $response->assertSessionHasNoErrors();
@@ -1628,6 +1818,7 @@
 
     $response = $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => 50000,
+        'receipt_key' => 'cash-transaction/receipt.jpg',
     ]);
 
     $response->assertSessionHasErrors('description');
@@ -1641,6 +1832,7 @@
 
     $response = $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => 50000,
+        'receipt_key' => 'cash-transaction/receipt.jpg',
     ]);
 
     $response->assertSessionHasErrors('description');
@@ -1655,6 +1847,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => '',
         'description' => 'Test',
+        'receipt_key' => 'cash-transaction/receipt.jpg',
     ]);
 
     $response->assertSessionHasErrors('amount');
@@ -1669,6 +1862,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => '',
         'description' => 'Test',
+        'receipt_key' => 'cash-transaction/receipt.jpg',
     ]);
 
     $response->assertSessionHasErrors('amount');
@@ -1683,6 +1877,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.deposit'), [
         'amount' => '100.500',
         'description' => 'Float amount',
+        'receipt_key' => 'cash-transaction/receipt.jpg',
     ]);
 
     $response->assertSessionHasNoErrors();
@@ -1698,6 +1893,7 @@
     $response = $this->post(route('admin.finance.cash-accounts.withdrawal'), [
         'amount' => '250.000',
         'description' => 'Float amount',
+        'receipt_key' => 'cash-transaction/receipt.jpg',
     ]);
 
     $response->assertSessionHasNoErrors();
diff --git a/tests/Feature/Admin/Finance/ExpenseTest.php b/tests/Feature/Admin/Finance/ExpenseTest.php
index 586a4d8..6214e48 100644
--- a/tests/Feature/Admin/Finance/ExpenseTest.php
+++ b/tests/Feature/Admin/Finance/ExpenseTest.php
@@ -52,6 +52,7 @@
     $response = $this->post(route('admin.finance.expenses.store'), [
         'amount' => 50000,
         'description' => 'Pembelian ATK',
+        'receipt_key' => 'expense/receipt-001.jpg',
     ]);
 
     $response
@@ -75,6 +76,7 @@
     $response = $this->post(route('admin.finance.expenses.store'), [
         'amount' => '',
         'description' => 'Test',
+        'receipt_key' => 'expense/receipt.jpg',
     ]);
 
     $response->assertSessionHasErrors('amount');
@@ -89,6 +91,7 @@
     $response = $this->post(route('admin.finance.expenses.store'), [
         'amount' => 0,
         'description' => 'Test',
+        'receipt_key' => 'expense/receipt.jpg',
     ]);
 
     $response->assertSessionHasErrors('amount');
@@ -103,11 +106,26 @@
     $response = $this->post(route('admin.finance.expenses.store'), [
         'amount' => 50000,
         'description' => '',
+        'receipt_key' => 'expense/receipt.jpg',
     ]);
 
     $response->assertSessionHasErrors('description');
 });
 
+test('expense receipt_key is required', function () {
+    $user = User::factory()->create();
+    $this->actingAs($user);
+
+    CashAccount::factory()->create(['balance' => 100000]);
+
+    $response = $this->post(route('admin.finance.expenses.store'), [
+        'amount' => 50000,
+        'description' => 'Test',
+    ]);
+
+    $response->assertSessionHasErrors('receipt_key');
+});
+
 test('expense fails when balance is insufficient', function () {
     $user = User::factory()->create();
     $this->actingAs($user);
@@ -117,9 +135,11 @@
     $response = $this->post(route('admin.finance.expenses.store'), [
         'amount' => 100000,
         'description' => 'Test',
+        'receipt_key' => 'expense/receipt.jpg',
     ]);
 
-    $response->assertSessionHasErrors('amount');
+    $response->assertRedirect();
+    expect(CashAccount::first()->balance)->toBe(50000);
 });
 
 test('expense can be updated', function () {
@@ -143,6 +163,7 @@
     $response = $this->put(route('admin.finance.expenses.update', $expense), [
         'amount' => 40000,
         'description' => 'Pembelian ATK Updated',
+        'receipt_key' => 'expense/receipt-updated.jpg',
     ]);
 
     $response
@@ -154,6 +175,32 @@
     expect($expense->description)->toBe('Pembelian ATK Updated');
 });
 
+test('expense update requires receipt_key', function () {
+    $user = User::factory()->create();
+    $this->actingAs($user);
+
+    $cashAccount = CashAccount::factory()->create(['balance' => 100000]);
+    $cashTransaction = CashTransaction::factory()->create([
+        'cash_account_id' => $cashAccount->id,
+        'created_by_id' => $user->id,
+        'type' => 'expense',
+        'amount' => 30000,
+        'balance_after' => 70000,
+    ]);
+    $expense = Expense::factory()->create([
+        'cash_transaction_id' => $cashTransaction->id,
+        'created_by_id' => $user->id,
+        'amount' => 30000,
+    ]);
+
+    $response = $this->put(route('admin.finance.expenses.update', $expense), [
+        'amount' => 40000,
+        'description' => 'Updated',
+    ]);
+
+    $response->assertSessionHasErrors('receipt_key');
+});
+
 test('expense can be deleted', function () {
     $user = User::factory()->create();
     $this->actingAs($user);
@@ -181,3 +228,33 @@
     $this->assertSoftDeleted('expenses', ['id' => $expense->id]);
     expect(CashAccount::first()->balance)->toBe(130000);
 });
+
+test('expense receipt_key max length is 500', function () {
+    $user = User::factory()->create();
+    $this->actingAs($user);
+
+    CashAccount::factory()->create(['balance' => 100000]);
+
+    $response = $this->post(route('admin.finance.expenses.store'), [
+        'amount' => 50000,
+        'description' => 'Test',
+        'receipt_key' => str_repeat('a', 501),
+    ]);
+
+    $response->assertSessionHasErrors('receipt_key');
+});
+
+test('expense receipt_key exactly 500 characters is accepted', function () {
+    $user = User::factory()->create();
+    $this->actingAs($user);
+
+    CashAccount::factory()->create(['balance' => 100000]);
+
+    $response = $this->post(route('admin.finance.expenses.store'), [
+        'amount' => 50000,
+        'description' => 'Test',
+        'receipt_key' => str_repeat('a', 500),
+    ]);
+
+    $response->assertSessionHasNoErrors();
+});