diff --git a/app/Models/Tenants/ExpectedExpense.php b/app/Models/Tenants/ExpectedExpense.php
index 7ad94e1..0600839 100644
--- a/app/Models/Tenants/ExpectedExpense.php
+++ b/app/Models/Tenants/ExpectedExpense.php
@@ -3,8 +3,10 @@
 namespace App\Models\Tenants;
 
 use App\Traits\BelongsToTenant;
+use Illuminate\Database\Eloquent\Builder;
 use Illuminate\Database\Eloquent\Model;
 use Illuminate\Database\Eloquent\Relations\BelongsTo;
+use Illuminate\Database\Eloquent\Relations\MorphTo;
 use Illuminate\Database\Eloquent\SoftDeletes;
 
 class ExpectedExpense extends Model
@@ -24,6 +26,8 @@ class ExpectedExpense extends Model
         'payment_status',
         'approval_status',
         'description',
+        'source_type',
+        'source_id',
         'created_by',
         'updated_by',
         'deleted_by',
@@ -42,6 +46,8 @@ class ExpectedExpense extends Model
      */
     public const TRANSACTION_TYPES = [
         'purchase' => '매입',
+        'card' => '카드결제',
+        'bill' => '발행어음',
         'advance' => '선급금',
         'suspense' => '가지급금',
         'rent' => '임대료',
@@ -131,4 +137,29 @@ public function getApprovalStatusLabelAttribute(): string
     {
         return self::APPROVAL_STATUSES[$this->approval_status] ?? $this->approval_status;
     }
+
+    /**
+     * 원본 소스 관계 (Polymorphic)
+     */
+    public function source(): MorphTo
+    {
+        return $this->morphTo();
+    }
+
+    /**
+     * 원본 소스로 검색
+     */
+    public function scopeBySource(Builder $query, string $sourceType, int $sourceId): Builder
+    {
+        return $query->where('source_type', $sourceType)
+            ->where('source_id', $sourceId);
+    }
+
+    /**
+     * 동기화된 레코드 여부
+     */
+    public function isSynced(): bool
+    {
+        return ! is_null($this->source_type) && ! is_null($this->source_id);
+    }
 }
diff --git a/app/Observers/ExpenseSync/BillExpenseSyncObserver.php b/app/Observers/ExpenseSync/BillExpenseSyncObserver.php
new file mode 100644
index 0000000..27003ba
--- /dev/null
+++ b/app/Observers/ExpenseSync/BillExpenseSyncObserver.php
@@ -0,0 +1,169 @@
+<?php
+
+namespace App\Observers\ExpenseSync;
+
+use App\Models\Tenants\Bill;
+use App\Models\Tenants\ExpectedExpense;
+
+/**
+ * 발행어음 데이터를 예상 지출(expected_expenses)로 자동 동기화
+ * (bill_type = 'issued' 인 경우만)
+ */
+class BillExpenseSyncObserver
+{
+    /**
+     * 어음 생성 시 → 발행어음인 경우 예상 지출 생성
+     */
+    public function created(Bill $bill): void
+    {
+        if ($this->isIssuedBill($bill)) {
+            $this->syncToExpectedExpense($bill);
+        }
+    }
+
+    /**
+     * 어음 수정 시 → 발행어음 상태 변경 처리
+     */
+    public function updated(Bill $bill): void
+    {
+        $wasIssued = $bill->getOriginal('bill_type') === 'issued';
+        $isIssued = $this->isIssuedBill($bill);
+
+        if ($isIssued) {
+            // 발행어음 → 동기화
+            $this->syncToExpectedExpense($bill);
+        } elseif ($wasIssued && ! $isIssued) {
+            // 발행어음에서 수취어음으로 변경 → 예상 지출 삭제
+            $this->deleteExpectedExpense($bill);
+        }
+    }
+
+    /**
+     * 어음 삭제 시 → 예상 지출 삭제
+     */
+    public function deleted(Bill $bill): void
+    {
+        if ($this->isIssuedBill($bill)) {
+            $this->deleteExpectedExpense($bill);
+        }
+    }
+
+    /**
+     * 어음 복원 시 → 발행어음인 경우 예상 지출 복원
+     */
+    public function restored(Bill $bill): void
+    {
+        if (! $this->isIssuedBill($bill)) {
+            return;
+        }
+
+        $expense = ExpectedExpense::withTrashed()
+            ->withoutGlobalScopes()
+            ->bySource('bills', $bill->id)
+            ->first();
+
+        if ($expense) {
+            $expense->restore();
+            $this->updateExpectedExpense($expense, $bill);
+        } else {
+            $this->createExpectedExpense($bill);
+        }
+    }
+
+    /**
+     * 어음 강제 삭제 시 → 예상 지출 강제 삭제
+     */
+    public function forceDeleted(Bill $bill): void
+    {
+        ExpectedExpense::withTrashed()
+            ->withoutGlobalScopes()
+            ->bySource('bills', $bill->id)
+            ->forceDelete();
+    }
+
+    /**
+     * 발행어음 여부 확인
+     */
+    protected function isIssuedBill(Bill $bill): bool
+    {
+        return $bill->bill_type === 'issued';
+    }
+
+    /**
+     * 예상 지출에 동기화
+     */
+    protected function syncToExpectedExpense(Bill $bill): void
+    {
+        $expense = ExpectedExpense::withoutGlobalScopes()
+            ->bySource('bills', $bill->id)
+            ->first();
+
+        if ($expense) {
+            $this->updateExpectedExpense($expense, $bill);
+        } else {
+            $this->createExpectedExpense($bill);
+        }
+    }
+
+    /**
+     * 예상 지출 삭제
+     */
+    protected function deleteExpectedExpense(Bill $bill): void
+    {
+        ExpectedExpense::withoutGlobalScopes()
+            ->bySource('bills', $bill->id)
+            ->delete();
+    }
+
+    /**
+     * 어음 상태 → 지급상태 매핑
+     */
+    protected function mapPaymentStatus(string $billStatus): string
+    {
+        return match ($billStatus) {
+            'paymentComplete', 'collectionComplete' => 'paid',
+            'dishonored' => 'overdue',
+            default => 'pending',
+        };
+    }
+
+    /**
+     * 예상 지출 생성
+     */
+    protected function createExpectedExpense(Bill $bill): void
+    {
+        ExpectedExpense::create([
+            'tenant_id' => $bill->tenant_id,
+            'expected_payment_date' => $bill->maturity_date, // 만기일을 예상 지급일로
+            'transaction_type' => 'bill',
+            'amount' => $bill->amount,
+            'client_id' => $bill->client_id,
+            'client_name' => $bill->client_name,
+            'bank_account_id' => $bill->bank_account_id,
+            'description' => $bill->note ?? "어음번호: {$bill->bill_number}",
+            'payment_status' => $this->mapPaymentStatus($bill->status),
+            'approval_status' => 'none',
+            'source_type' => 'bills',
+            'source_id' => $bill->id,
+            'created_by' => $bill->created_by,
+            'updated_by' => $bill->updated_by,
+        ]);
+    }
+
+    /**
+     * 예상 지출 업데이트
+     */
+    protected function updateExpectedExpense(ExpectedExpense $expense, Bill $bill): void
+    {
+        $expense->update([
+            'expected_payment_date' => $bill->maturity_date,
+            'amount' => $bill->amount,
+            'client_id' => $bill->client_id,
+            'client_name' => $bill->client_name,
+            'bank_account_id' => $bill->bank_account_id,
+            'description' => $bill->note ?? "어음번호: {$bill->bill_number}",
+            'payment_status' => $this->mapPaymentStatus($bill->status),
+            'updated_by' => $bill->updated_by,
+        ]);
+    }
+}
diff --git a/app/Observers/ExpenseSync/PurchaseExpenseSyncObserver.php b/app/Observers/ExpenseSync/PurchaseExpenseSyncObserver.php
new file mode 100644
index 0000000..c6bf077
--- /dev/null
+++ b/app/Observers/ExpenseSync/PurchaseExpenseSyncObserver.php
@@ -0,0 +1,120 @@
+<?php
+
+namespace App\Observers\ExpenseSync;
+
+use App\Models\Tenants\ExpectedExpense;
+use App\Models\Tenants\Purchase;
+
+/**
+ * 매입 데이터를 예상 지출(expected_expenses)로 자동 동기화
+ */
+class PurchaseExpenseSyncObserver
+{
+    /**
+     * 매입 생성 시 → 예상 지출 생성
+     */
+    public function created(Purchase $purchase): void
+    {
+        $this->syncToExpectedExpense($purchase);
+    }
+
+    /**
+     * 매입 수정 시 → 예상 지출 업데이트
+     */
+    public function updated(Purchase $purchase): void
+    {
+        $this->syncToExpectedExpense($purchase);
+    }
+
+    /**
+     * 매입 삭제 시 → 예상 지출 삭제
+     */
+    public function deleted(Purchase $purchase): void
+    {
+        ExpectedExpense::withoutGlobalScopes()
+            ->bySource('purchases', $purchase->id)
+            ->delete();
+    }
+
+    /**
+     * 매입 복원 시 → 예상 지출 복원
+     */
+    public function restored(Purchase $purchase): void
+    {
+        // 기존 soft deleted 레코드가 있으면 복원, 없으면 생성
+        $expense = ExpectedExpense::withTrashed()
+            ->withoutGlobalScopes()
+            ->bySource('purchases', $purchase->id)
+            ->first();
+
+        if ($expense) {
+            $expense->restore();
+            $this->updateExpectedExpense($expense, $purchase);
+        } else {
+            $this->syncToExpectedExpense($purchase);
+        }
+    }
+
+    /**
+     * 매입 강제 삭제 시 → 예상 지출 강제 삭제
+     */
+    public function forceDeleted(Purchase $purchase): void
+    {
+        ExpectedExpense::withTrashed()
+            ->withoutGlobalScopes()
+            ->bySource('purchases', $purchase->id)
+            ->forceDelete();
+    }
+
+    /**
+     * 예상 지출에 동기화
+     */
+    protected function syncToExpectedExpense(Purchase $purchase): void
+    {
+        $expense = ExpectedExpense::withoutGlobalScopes()
+            ->bySource('purchases', $purchase->id)
+            ->first();
+
+        if ($expense) {
+            $this->updateExpectedExpense($expense, $purchase);
+        } else {
+            $this->createExpectedExpense($purchase);
+        }
+    }
+
+    /**
+     * 예상 지출 생성
+     */
+    protected function createExpectedExpense(Purchase $purchase): void
+    {
+        ExpectedExpense::create([
+            'tenant_id' => $purchase->tenant_id,
+            'expected_payment_date' => $purchase->purchase_date,
+            'transaction_type' => 'purchase',
+            'amount' => $purchase->total_amount,
+            'client_id' => $purchase->client_id,
+            'description' => $purchase->description ?? "매입번호: {$purchase->purchase_number}",
+            'payment_status' => $purchase->withdrawal_id ? 'paid' : 'pending',
+            'approval_status' => 'none',
+            'source_type' => 'purchases',
+            'source_id' => $purchase->id,
+            'created_by' => $purchase->created_by,
+            'updated_by' => $purchase->updated_by,
+        ]);
+    }
+
+    /**
+     * 예상 지출 업데이트
+     */
+    protected function updateExpectedExpense(ExpectedExpense $expense, Purchase $purchase): void
+    {
+        $expense->update([
+            'expected_payment_date' => $purchase->purchase_date,
+            'amount' => $purchase->total_amount,
+            'client_id' => $purchase->client_id,
+            'description' => $purchase->description ?? "매입번호: {$purchase->purchase_number}",
+            'payment_status' => $purchase->withdrawal_id ? 'paid' : 'pending',
+            'updated_by' => $purchase->updated_by,
+        ]);
+    }
+}
diff --git a/app/Observers/ExpenseSync/WithdrawalExpenseSyncObserver.php b/app/Observers/ExpenseSync/WithdrawalExpenseSyncObserver.php
new file mode 100644
index 0000000..1b1ec9b
--- /dev/null
+++ b/app/Observers/ExpenseSync/WithdrawalExpenseSyncObserver.php
@@ -0,0 +1,158 @@
+<?php
+
+namespace App\Observers\ExpenseSync;
+
+use App\Models\Tenants\ExpectedExpense;
+use App\Models\Tenants\Withdrawal;
+
+/**
+ * 카드결제 데이터를 예상 지출(expected_expenses)로 자동 동기화
+ * (payment_method = 'card' 인 경우만)
+ */
+class WithdrawalExpenseSyncObserver
+{
+    /**
+     * 출금 생성 시 → 카드결제인 경우 예상 지출 생성
+     */
+    public function created(Withdrawal $withdrawal): void
+    {
+        if ($this->isCardPayment($withdrawal)) {
+            $this->syncToExpectedExpense($withdrawal);
+        }
+    }
+
+    /**
+     * 출금 수정 시 → 카드결제 상태 변경 처리
+     */
+    public function updated(Withdrawal $withdrawal): void
+    {
+        $wasCard = $withdrawal->getOriginal('payment_method') === 'card';
+        $isCard = $this->isCardPayment($withdrawal);
+
+        if ($isCard) {
+            // 카드결제 → 동기화
+            $this->syncToExpectedExpense($withdrawal);
+        } elseif ($wasCard && ! $isCard) {
+            // 카드결제에서 다른 방법으로 변경 → 예상 지출 삭제
+            $this->deleteExpectedExpense($withdrawal);
+        }
+    }
+
+    /**
+     * 출금 삭제 시 → 예상 지출 삭제
+     */
+    public function deleted(Withdrawal $withdrawal): void
+    {
+        if ($this->isCardPayment($withdrawal)) {
+            $this->deleteExpectedExpense($withdrawal);
+        }
+    }
+
+    /**
+     * 출금 복원 시 → 카드결제인 경우 예상 지출 복원
+     */
+    public function restored(Withdrawal $withdrawal): void
+    {
+        if (! $this->isCardPayment($withdrawal)) {
+            return;
+        }
+
+        $expense = ExpectedExpense::withTrashed()
+            ->withoutGlobalScopes()
+            ->bySource('withdrawals', $withdrawal->id)
+            ->first();
+
+        if ($expense) {
+            $expense->restore();
+            $this->updateExpectedExpense($expense, $withdrawal);
+        } else {
+            $this->createExpectedExpense($withdrawal);
+        }
+    }
+
+    /**
+     * 출금 강제 삭제 시 → 예상 지출 강제 삭제
+     */
+    public function forceDeleted(Withdrawal $withdrawal): void
+    {
+        ExpectedExpense::withTrashed()
+            ->withoutGlobalScopes()
+            ->bySource('withdrawals', $withdrawal->id)
+            ->forceDelete();
+    }
+
+    /**
+     * 카드결제 여부 확인
+     */
+    protected function isCardPayment(Withdrawal $withdrawal): bool
+    {
+        return $withdrawal->payment_method === 'card';
+    }
+
+    /**
+     * 예상 지출에 동기화
+     */
+    protected function syncToExpectedExpense(Withdrawal $withdrawal): void
+    {
+        $expense = ExpectedExpense::withoutGlobalScopes()
+            ->bySource('withdrawals', $withdrawal->id)
+            ->first();
+
+        if ($expense) {
+            $this->updateExpectedExpense($expense, $withdrawal);
+        } else {
+            $this->createExpectedExpense($withdrawal);
+        }
+    }
+
+    /**
+     * 예상 지출 삭제
+     */
+    protected function deleteExpectedExpense(Withdrawal $withdrawal): void
+    {
+        ExpectedExpense::withoutGlobalScopes()
+            ->bySource('withdrawals', $withdrawal->id)
+            ->delete();
+    }
+
+    /**
+     * 예상 지출 생성
+     */
+    protected function createExpectedExpense(Withdrawal $withdrawal): void
+    {
+        ExpectedExpense::create([
+            'tenant_id' => $withdrawal->tenant_id,
+            'expected_payment_date' => $withdrawal->withdrawal_date,
+            'transaction_type' => 'card',
+            'amount' => $withdrawal->amount,
+            'client_id' => $withdrawal->client_id,
+            'client_name' => $withdrawal->client_name ?? $withdrawal->merchant_name,
+            'bank_account_id' => $withdrawal->bank_account_id,
+            'account_code' => $withdrawal->account_code,
+            'description' => $withdrawal->description,
+            'payment_status' => 'paid', // 카드결제는 이미 결제 완료 상태
+            'approval_status' => 'none',
+            'source_type' => 'withdrawals',
+            'source_id' => $withdrawal->id,
+            'created_by' => $withdrawal->created_by,
+            'updated_by' => $withdrawal->updated_by,
+        ]);
+    }
+
+    /**
+     * 예상 지출 업데이트
+     */
+    protected function updateExpectedExpense(ExpectedExpense $expense, Withdrawal $withdrawal): void
+    {
+        $expense->update([
+            'expected_payment_date' => $withdrawal->withdrawal_date,
+            'amount' => $withdrawal->amount,
+            'client_id' => $withdrawal->client_id,
+            'client_name' => $withdrawal->client_name ?? $withdrawal->merchant_name,
+            'bank_account_id' => $withdrawal->bank_account_id,
+            'account_code' => $withdrawal->account_code,
+            'description' => $withdrawal->description,
+            'updated_by' => $withdrawal->updated_by,
+        ]);
+    }
+}
diff --git a/app/Providers/AppServiceProvider.php b/app/Providers/AppServiceProvider.php
index 3cda80a..528e54f 100644
--- a/app/Providers/AppServiceProvider.php
+++ b/app/Providers/AppServiceProvider.php
@@ -12,6 +12,8 @@
 use App\Models\Tenants\Deposit;
 use App\Models\Tenants\ExpectedExpense;
 use App\Models\Tenants\Stock;
+use App\Models\Tenants\Bill;
+use App\Models\Tenants\Purchase;
 use App\Models\Tenants\Tenant;
 use App\Models\Tenants\Withdrawal;
 use App\Observers\MenuObserver;
@@ -24,6 +26,9 @@
 use App\Observers\TodayIssue\OrderIssueObserver;
 use App\Observers\TodayIssue\StockIssueObserver;
 use App\Observers\TodayIssue\WithdrawalIssueObserver;
+use App\Observers\ExpenseSync\BillExpenseSyncObserver;
+use App\Observers\ExpenseSync\PurchaseExpenseSyncObserver;
+use App\Observers\ExpenseSync\WithdrawalExpenseSyncObserver;
 use Illuminate\Database\Eloquent\Builder;
 use Illuminate\Database\Eloquent\Relations\Relation;
 use Illuminate\Support\Facades\DB;
@@ -83,5 +88,10 @@ public function boot(): void
         Client::observe(ClientIssueObserver::class);
         Deposit::observe(DepositIssueObserver::class);
         Withdrawal::observe(WithdrawalIssueObserver::class);
+
+        // 예상 지출 자동 동기화 (매입/카드결제/발행어음 → expected_expenses)
+        Purchase::observe(PurchaseExpenseSyncObserver::class);
+        Withdrawal::observe(WithdrawalExpenseSyncObserver::class);
+        Bill::observe(BillExpenseSyncObserver::class);
     }
 }
diff --git a/database/migrations/2026_01_23_100000_add_source_fields_to_expected_expenses_table.php b/database/migrations/2026_01_23_100000_add_source_fields_to_expected_expenses_table.php
new file mode 100644
index 0000000..4f7cb4c
--- /dev/null
+++ b/database/migrations/2026_01_23_100000_add_source_fields_to_expected_expenses_table.php
@@ -0,0 +1,27 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::table('expected_expenses', function (Blueprint $table) {
+            $table->string('source_type', 50)->nullable()->after('description')->comment('원본 테이블: purchases/withdrawals/bills');
+            $table->unsignedBigInteger('source_id')->nullable()->after('source_type')->comment('원본 레코드 ID');
+
+            // 복합 인덱스: 동기화된 레코드 검색용
+            $table->index(['source_type', 'source_id'], 'idx_source');
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::table('expected_expenses', function (Blueprint $table) {
+            $table->dropIndex('idx_source');
+            $table->dropColumn(['source_type', 'source_id']);
+        });
+    }
+};