diff --git a/app/Services/CalendarService.php b/app/Services/CalendarService.php
index bdd87ae..9d44415 100644
--- a/app/Services/CalendarService.php
+++ b/app/Services/CalendarService.php
@@ -4,6 +4,7 @@
 
 use App\Models\Construction\Contract;
 use App\Models\Production\WorkOrder;
+use App\Models\Tenants\Bill;
 use App\Models\Tenants\Leave;
 use App\Models\Tenants\Schedule;
 use Illuminate\Support\Collection;
@@ -16,6 +17,7 @@
  * - 계약(Contract): 시공 일정
  * - 휴가(Leave): 직원 휴가 일정
  * - 일정(Schedule): 본사 공통 일정 + 테넌트 일정 (세금 신고, 공휴일 등)
+ * - 어음(Bill): 어음 만기일 일정
  */
 class CalendarService extends Service
 {
@@ -24,7 +26,7 @@ class CalendarService extends Service
      *
      * @param  string  $startDate  조회 시작일 (Y-m-d)
      * @param  string  $endDate  조회 종료일 (Y-m-d)
-     * @param  string|null  $type  일정 타입 필터 (schedule|order|construction|other|null=전체)
+     * @param  string|null  $type  일정 타입 필터 (schedule|order|construction|other|bill|null=전체)
      * @param  string|null  $departmentFilter  부서 필터 (all|department|personal)
      */
     public function getSchedules(
@@ -64,6 +66,13 @@ public function getSchedules(
             );
         }
 
+        // 어음 만기일
+        if ($type === null || $type === 'bill') {
+            $schedules = $schedules->merge(
+                $this->getBillSchedules($tenantId, $startDate, $endDate)
+            );
+        }
+
         // startDate 기준 정렬
         $sortedSchedules = $schedules
             ->sortBy('startDate')
@@ -331,4 +340,46 @@ private function getGeneralSchedules(
             ];
         });
     }
+
+    /**
+     * 어음 만기일 일정 조회
+     */
+    private function getBillSchedules(
+        int $tenantId,
+        string $startDate,
+        string $endDate
+    ): Collection {
+        $excludedStatuses = [
+            'paymentComplete',
+            'dishonored',
+        ];
+
+        $bills = Bill::query()
+            ->where('tenant_id', $tenantId)
+            ->whereNotNull('maturity_date')
+            ->where('maturity_date', '>=', $startDate)
+            ->where('maturity_date', '<=', $endDate)
+            ->whereNotIn('status', $excludedStatuses)
+            ->orderBy('maturity_date')
+            ->limit(100)
+            ->get();
+
+        return $bills->map(function ($bill) {
+            $clientName = $bill->display_client_name ?? $bill->client_name ?? '';
+
+            return [
+                'id' => 'bill_'.$bill->id,
+                'title' => '[만기] '.$clientName.' '.number_format($bill->amount).'원',
+                'startDate' => $bill->maturity_date->format('Y-m-d'),
+                'endDate' => $bill->maturity_date->format('Y-m-d'),
+                'startTime' => null,
+                'endTime' => null,
+                'isAllDay' => true,
+                'type' => 'bill',
+                'department' => null,
+                'personName' => null,
+                'color' => null,
+            ];
+        });
+    }
 }