diff --git a/modules/_bundled/sirsoft-ecommerce/src/Repositories/Contracts/OrderCashReceiptRepositoryInterface.php b/modules/_bundled/sirsoft-ecommerce/src/Repositories/Contracts/OrderCashReceiptRepositoryInterface.php
index 4c480c76..cb31644a 100644
--- a/modules/_bundled/sirsoft-ecommerce/src/Repositories/Contracts/OrderCashReceiptRepositoryInterface.php
+++ b/modules/_bundled/sirsoft-ecommerce/src/Repositories/Contracts/OrderCashReceiptRepositoryInterface.php
@@ -53,4 +53,18 @@ interface OrderCashReceiptRepositoryInterface
      * @return OrderCashReceipt|null 이력 (없으면 null)
      */
     public function findByReceiptKey(string $receiptKey): ?OrderCashReceipt;
+
+    /**
+     * 주문의 발급(issue) 시도 횟수를 반환합니다. (성공/실패 무관)
+     *
+     * 프로바이더가 발급 요청 식별자를 회차로 구분해야 할 때 쓰인다.
+     * 예: 토스페이먼츠는 동일 orderId 재사용을 중복으로 거부하므로 회차 접미가 필요하다.
+     *
+     * 실패한 시도까지 세는 이유 — 프로바이더에 요청이 도달한 뒤 응답만 실패했을 수 있고,
+     * 그 경우 같은 식별자를 재사용하면 중복 거부된다.
+     *
+     * @param  Order  $order  주문 모델
+     * @return int 발급 이력 건수
+     */
+    public function countIssues(Order $order): int;
 }
diff --git a/modules/_bundled/sirsoft-ecommerce/src/Repositories/OrderCashReceiptRepository.php b/modules/_bundled/sirsoft-ecommerce/src/Repositories/OrderCashReceiptRepository.php
index c1d6d99b..9037b733 100644
--- a/modules/_bundled/sirsoft-ecommerce/src/Repositories/OrderCashReceiptRepository.php
+++ b/modules/_bundled/sirsoft-ecommerce/src/Repositories/OrderCashReceiptRepository.php
@@ -94,4 +94,15 @@ class OrderCashReceiptRepository implements OrderCashReceiptRepositoryInterface
             ->orderByDesc('id')
             ->first();
     }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function countIssues(Order $order): int
+    {
+        return $this->model->newQuery()
+            ->where('order_id', $order->id)
+            ->where('transaction_type', CashReceiptTransactionType::ISSUE->value)
+            ->count();
+    }
 }
diff --git a/modules/_bundled/sirsoft-ecommerce/src/Services/CashReceiptService.php b/modules/_bundled/sirsoft-ecommerce/src/Services/CashReceiptService.php
index f46cf88b..b08ae825 100644
--- a/modules/_bundled/sirsoft-ecommerce/src/Services/CashReceiptService.php
+++ b/modules/_bundled/sirsoft-ecommerce/src/Services/CashReceiptService.php
@@ -106,6 +106,10 @@ class CashReceiptService
             'tax_free_amount' => $target['tax_free_amount'],
             'order_name' => $this->buildOrderName($order),
             'order_number' => $order->order_number,
+            // 이번 발급의 회차 (1부터). 프로바이더가 발급 요청 식별자를 회차로 구분할 때 사용한다.
+            // 토스는 동일 orderId 재사용을 중복 거부하므로 "{order_number}-cr{seq}" 로 접미한다.
+            // 프로바이더 종속 문자열 조립은 리스너가 하고, 코어는 숫자만 제공한다.
+            'issue_sequence' => $this->repository->countIssues($order) + 1,
         ];
 
         $result = HookManager::applyFilters(
diff --git a/modules/_bundled/sirsoft-ecommerce/tests/Unit/Services/CashReceiptServiceTest.php b/modules/_bundled/sirsoft-ecommerce/tests/Unit/Services/CashReceiptServiceTest.php
index 81cfc8e2..f1d23f2c 100644
--- a/modules/_bundled/sirsoft-ecommerce/tests/Unit/Services/CashReceiptServiceTest.php
+++ b/modules/_bundled/sirsoft-ecommerce/tests/Unit/Services/CashReceiptServiceTest.php
@@ -591,6 +591,67 @@ class CashReceiptServiceTest extends ModuleTestCase
         );
     }
 
+    #[Test]
+    public function 최초_발급의_회차는_1이다(): void
+    {
+        $this->registerProvider();
+        $order = $this->makeOrder(11000, 11000, 0);
+
+        $this->service()->issue($order, CashReceiptType::INCOME, self::IDENTIFIER);
+
+        $this->assertSame(1, $this->issueCalls[0]['payload']['issue_sequence']);
+    }
+
+    #[Test]
+    public function 재발급의_회차는_증가한다(): void
+    {
+        // 토스는 동일 orderId 재사용을 중복 거부하므로 재발급마다 회차가 달라야 한다.
+        $this->registerProvider();
+        $order = $this->makeOrder(11000, 11000, 0);
+        $this->service()->issue($order, CashReceiptType::INCOME, self::IDENTIFIER);
+
+        $order->update(['total_cash_equivalent_amount' => 5500, 'total_tax_amount' => 5500]);
+        $this->service()->syncFromOrder($order->fresh(), '부분환불');
+
+        $this->assertSame(1, $this->issueCalls[0]['payload']['issue_sequence']);
+        $this->assertSame(2, $this->issueCalls[1]['payload']['issue_sequence'], '재발급은 2회차');
+    }
+
+    #[Test]
+    public function 발급이_실패해도_다음_회차는_증가한다(): void
+    {
+        // 프로바이더에 요청이 도달한 뒤 응답만 실패했을 수 있다.
+        // 같은 식별자를 재사용하면 중복 거부되므로 실패한 시도도 회차를 소모해야 한다.
+        $this->registerProvider();
+        $this->issueShouldFail = true;
+        $order = $this->makeOrder(11000, 11000, 0);
+
+        $this->service()->issue($order, CashReceiptType::INCOME, self::IDENTIFIER);
+        $this->assertSame(1, $this->issueCalls[0]['payload']['issue_sequence']);
+
+        $this->issueShouldFail = false;
+        $this->service()->issue($order->fresh(), CashReceiptType::INCOME, self::IDENTIFIER);
+
+        $this->assertSame(2, $this->issueCalls[1]['payload']['issue_sequence'], '실패한 1회차를 건너뛴다');
+    }
+
+    #[Test]
+    public function 취소_이력은_발급_회차를_소모하지_않는다(): void
+    {
+        $this->registerProvider();
+        $order = $this->makeOrder(11000, 11000, 0);
+        $this->service()->issue($order, CashReceiptType::INCOME, self::IDENTIFIER);
+
+        $this->service()->cancelAll($order->fresh(), '전액취소');
+
+        // 취소 1건이 남았지만 발급 회차는 issue 이력만 센다
+        $repository = app(OrderCashReceiptRepositoryInterface::class);
+        $this->assertSame(1, $repository->countIssues($order->fresh()));
+
+        $this->service()->issue($order->fresh(), CashReceiptType::INCOME, self::IDENTIFIER);
+        $this->assertSame(2, $this->issueCalls[1]['payload']['issue_sequence']);
+    }
+
     #[Test]
     public function 주문_삭제_시_현금영수증_이력도_명시적으로_삭제된다(): void
     {
diff --git a/modules/_bundled/sirsoft-ecommerce/tests/scenarios/cash-receipt-infrastructure.yaml b/modules/_bundled/sirsoft-ecommerce/tests/scenarios/cash-receipt-infrastructure.yaml
index 79c0570c..504f13ab 100644
--- a/modules/_bundled/sirsoft-ecommerce/tests/scenarios/cash-receipt-infrastructure.yaml
+++ b/modules/_bundled/sirsoft-ecommerce/tests/scenarios/cash-receipt-infrastructure.yaml
@@ -80,6 +80,10 @@ effects:
   - issue_delegates_to_provider_filter         # 발급을 cash_receipt.issue 필터로 위임
   - cancel_delegates_without_amount            # 취소 필터에 금액을 넘기지 않음(항상 전액취소)
   - issue_records_ledger_and_payment_summary   # 이력 + 결제 요약 컬럼 동시 갱신
+  - issue_sequence_starts_at_one               # 최초 발급 회차 = 1
+  - issue_sequence_increments_on_reissue       # 재발급마다 회차 증가 (토스 orderId 중복 거부 회피)
+  - failed_issue_consumes_sequence             # 실패한 발급도 회차를 소모 (프로바이더 도달 후 실패 대비)
+  - cancel_does_not_consume_issue_sequence     # 취소 이력은 발급 회차를 소모하지 않음
 
   # syncFromOrder — 무상태 재계산
   - sync_reissues_on_amount_change             # 감소·증가 모두 전체취소 후 전액 재발급