diff --git a/backend/app/services/payment_chase.py b/backend/app/services/payment_chase.py
index e3999518..76bcf9b3 100644
--- a/backend/app/services/payment_chase.py
+++ b/backend/app/services/payment_chase.py
@@ -20,11 +20,7 @@ def chase_period_money(
     due_amount: Any,
     transfers: Iterable[Mapping[str, Any]],
 ) -> Tuple[Decimal, Decimal]:
-    """
-    与缴费信息期次口径一致：
-    已缴 = dfj + jfqrz + yjf；欠缴 = max(应缴 − 已缴, 0)。
-    返回 (paidAmount, arrearsAmount)。
-    """
+    """已缴 = 仅 yjf；欠缴 = max(应缴 − 已缴, 0)。"""
     summary: Dict[str, Any] = summarize_period(
         due_amount=due_amount, transfers=transfers
     )
diff --git a/backend/app/services/sample_payment_period_summary.py b/backend/app/services/sample_payment_period_summary.py
index fe8b72dc..0df9bd70 100644
--- a/backend/app/services/sample_payment_period_summary.py
+++ b/backend/app/services/sample_payment_period_summary.py
@@ -17,7 +17,7 @@ def _status(row: Mapping[str, Any], *keys: str) -> str:
     return ""
 
 
-_DISPLAY_PAID_STATUSES = ("dfj", "jfqrz", "yjf")
+_DISPLAY_PAID_STATUSES = ("yjf",)
 
 
 def summarize_period(
@@ -26,7 +26,7 @@ def summarize_period(
     transfers: Iterable[Mapping[str, Any]],
 ) -> Dict[str, Any]:
     """
-    displayPaidAmount: dfj + jfqrz + yjf 合计（列表「已缴费金额」）
+    displayPaidAmount: 已缴费金额仅计付款完成(yjf)
     arrearsAmount: max(due - displayPaidAmount, 0)
     financeAudit: jfqrz > (confirmed>=due 且无确认中 → yjf) > (0<confirmed → partial) > dfj
     payDate: 首笔 transferTime 的日期部分（调用方应按 create_time ASC 传入）
diff --git a/backend/tests/test_payment_chase.py b/backend/tests/test_payment_chase.py
index 1780f8a1..8342b724 100644
--- a/backend/tests/test_payment_chase.py
+++ b/backend/tests/test_payment_chase.py
@@ -12,8 +12,8 @@ from app.services.payment_chase import (
 
 
 class TestChase(unittest.TestCase):
-    def test_chase_paid_includes_dfj_jfqrz_yjf(self):
-        """与缴费信息期次一致：已缴 = dfj + jfqrz + yjf"""
+    def test_chase_paid_only_counts_yjf(self):
+        """已缴 = 仅 yjf；欠缴 = 应缴 − 已缴"""
         paid, arrears = chase_period_money(
             due_amount=Decimal("1000"),
             transfers=[
@@ -34,10 +34,10 @@ class TestChase(unittest.TestCase):
                 },
             ],
         )
-        self.assertEqual(paid, Decimal("600"))
-        self.assertEqual(arrears, Decimal("400"))
+        self.assertEqual(paid, Decimal("100"))
+        self.assertEqual(arrears, Decimal("900"))
 
-    def test_chase_full_display_paid_not_candidate(self):
+    def test_chase_dfj_only_still_has_arrears(self):
         paid, arrears = chase_period_money(
             due_amount=Decimal("500"),
             transfers=[
@@ -48,9 +48,9 @@ class TestChase(unittest.TestCase):
                 }
             ],
         )
-        self.assertEqual(paid, Decimal("500"))
-        self.assertEqual(arrears, Decimal("0"))
-        self.assertFalse(
+        self.assertEqual(paid, Decimal("0"))
+        self.assertEqual(arrears, Decimal("500"))
+        self.assertTrue(
             is_chase_candidate(
                 due_date=date(2026, 9, 1),
                 today=date(2026, 10, 9),
diff --git a/backend/tests/test_sample_payment_period_summary.py b/backend/tests/test_sample_payment_period_summary.py
index 3cc5144d..515c643a 100644
--- a/backend/tests/test_sample_payment_period_summary.py
+++ b/backend/tests/test_sample_payment_period_summary.py
@@ -18,7 +18,7 @@ class TestPeriodSummary(unittest.TestCase):
         self.assertEqual(r["payTypeSummary"], "")
         self.assertEqual(r["financeAudit"], "dfj")
 
-    def test_dfj_counts_as_display_paid(self):
+    def test_dfj_does_not_count_as_display_paid(self):
         r = summarize_period(
             due_amount=Decimal("1000"),
             transfers=[
@@ -30,8 +30,8 @@ class TestPeriodSummary(unittest.TestCase):
                 }
             ],
         )
-        self.assertEqual(r["displayPaidAmount"], Decimal("400"))
-        self.assertEqual(r["arrearsAmount"], Decimal("600"))
+        self.assertEqual(r["displayPaidAmount"], Decimal("0"))
+        self.assertEqual(r["arrearsAmount"], Decimal("1000"))
         self.assertEqual(r["payDate"], "2026-04-19")
 
     def test_multi_transfer_summary(self):
@@ -90,5 +90,5 @@ class TestPeriodSummary(unittest.TestCase):
                 }
             ],
         )
-        self.assertEqual(r["displayPaidAmount"], Decimal("2000"))
+        self.assertEqual(r["displayPaidAmount"], Decimal("0"))
         self.assertEqual(r["financeAudit"], "jfqrz")