diff --git a/app/Http/Controllers/Business/Pages.php b/app/Http/Controllers/Business/Pages.php
index 829e8ac4..90ad36b8 100644
--- a/app/Http/Controllers/Business/Pages.php
+++ b/app/Http/Controllers/Business/Pages.php
@@ -372,6 +372,10 @@ class Pages extends Controller
         $jdSofiaGuobu = '(' . $jdSofiaPay . ' - COALESCE(income_amount, 0)) > 0.005';
         $rules['差额=订单实付包含商家承担优惠和以旧换新国补'] = $jdSofiaGuard . ' AND ' . $jdSofiaGuobu;
         $rules['差额=订单实付包含商家承担优惠'] = $jdSofiaGuard . ' AND NOT (' . $jdSofiaGuobu . ')';
+        // 拼多多全额退款：先于通用「未减优惠/冲减」判定，避免抵减项把退款单误标成其他原因。
+        $pddFullRefundHit = "platform = '拼多多'"
+            . ' AND ABS(COALESCE(income_amount, 0) + COALESCE(refund_amount, 0)) <= 0.02';
+        $rules['订单实付含已退款部分'] = $pddFullRefundHit;
         // C 方案：这三条是"通用等式档"——口径（卖家实收 / 应付已付）能对上账单的行让位给口径兜底
         // （归零 + 口径标识），只有口径也对不上时才显示这三档，避免把口径差标成一堆"未减优惠/冲减"。
         $notBasisMarked = self::receiptReasonNotBasisMarkedSql();
@@ -410,7 +414,18 @@ class Pages extends Controller
             . ' OR ' . $refundGapHit($refundEvidence['cancelled_sum'])
             . ' OR ' . $refundGapNetHit($refundEvidence['refund_sum'])
             . ' OR ' . $refundFullHit($refundEvidence['refund_sum'])
-            . ') ELSE 0 END = 1) OR ' . $taoRefundHit;
+            . ') ELSE 0 END = 1) OR ' . $taoRefundHit . ' OR ' . $pddFullRefundHit;
+
+        // 拼多多部分退款：账单收入高于聚水潭买家实付，且扣除优惠/冲减后仍有正向小额差额，
+        // 与「多多支付立减」等平台支付类补贴一致；只标注原因，不改差额和收入。
+        $pddPaymentDiscount = '(' . $effective . ' - COALESCE(discount_amount, 0) - COALESCE(offset_amount, 0))';
+        $rules['差额=平台支付立减'] = "platform = '拼多多'"
+            . " AND match_status = '已匹配'"
+            . ' AND ' . $effective . ' > 0.005'
+            . ' AND COALESCE(refund_amount, 0) < -0.005'
+            . ' AND ' . $pddPaymentDiscount . ' > 0.005'
+            . ' AND ' . $pddPaymentDiscount . ' <= 20.005'
+            . ' AND ' . $notBasisMarked;
 
         // 1688 先采后付订单的订单实付包含平台红包补贴，但支付宝实际到账是扣除补贴后的现金；
         // 仅对已匹配、负差额、无优惠/冲减/退款且当前没有口径标识的行标注，不改差额金额。
@@ -601,6 +616,11 @@ class Pages extends Controller
         if (abs($product) < 0.005) {
             return ($row->planting_amount ?? null) !== null ? $label . '取数为0（种菜）' : $label . '取数为0';
         }
+        // 拼多多全额退款优先于其它抵减等式：退款后实际净收款为 0，不应再落成优惠/冲减异常。
+        if (($row->platform ?? '') === '拼多多'
+            && abs($income + (float) ($row->refund_amount ?? 0)) <= 0.02) {
+            return '订单实付含已退款部分';
+        }
         // 得物负差额：差额与联合营销费未让利尾数吻合（营销费支出 + 差额恰为整数）→「订单实付未减联合营销费」。
         // 放在通用「未减冲减/优惠」等式之前：得物这类行的差额常恰好等于冲减（营销费）金额，需优先给出具体项备注。
         if (($row->platform ?? '') === '得物' && $difference < -0.005) {
@@ -707,6 +727,17 @@ class Pages extends Controller
             }
         }
 
+        // 拼多多部分退款：差额扣除优惠/冲减后，剩余部分与平台支付立减一致。
+        $pddPaymentDiscount = $difference - $discount - $offset;
+        if (($row->platform ?? '') === '拼多多'
+            && ! $basisMarked
+            && $difference > 0.005
+            && (float) ($row->refund_amount ?? 0) < -0.005
+            && $pddPaymentDiscount > 0.005
+            && $pddPaymentDiscount <= 20.005) {
+            return '差额=平台支付立减';
+        }
+
         // 原因优先：上面的规则都没命中时，如果这行的口径（卖家实收 / 应付已付）能对上账单，
         // 就按口径兜底——差额按 0 展示、口径标识在「匹配原因」列，不再当异常。
         $rawRemark = trim((string) ($row->remark ?? ''));
@@ -1661,8 +1692,8 @@ class Pages extends Controller
         // 联动统计要跑几次全表聚合，短时间内重复请求（页面加载 + 下拉刷新）直接吃缓存
         $cacheKey = 'performance-details-facets:' . md5(serialize([$month, $filters, $orderNo]));
 
-        // 数据按天同步，缓存 10 分钟：大幅降低大平台（拼多多等）的联动等待。
-        return response()->json(cache()->remember($cacheKey, now()->addSeconds(600), function () use ($month, $filters, $orderNo) {
+        // 数据按天同步；联动统计会扫全月，缓存 1 小时，避免相同筛选反复等待。
+        return response()->json(cache()->remember($cacheKey, now()->addHour(), function () use ($month, $filters, $orderNo) {
             return [
                 'month' => substr($month, 0, 7),
                 'facets' => $this->receiptOrderMatchFacets($month, $filters, $orderNo),
diff --git a/tests/Unit/EcommerceFinance/PerformanceDifferenceRemarkTest.php b/tests/Unit/EcommerceFinance/PerformanceDifferenceRemarkTest.php
new file mode 100644
index 00000000..bf131158
--- /dev/null
+++ b/tests/Unit/EcommerceFinance/PerformanceDifferenceRemarkTest.php
@@ -0,0 +1,71 @@
+<?php
+
+namespace Tests\Unit\EcommerceFinance;
+
+use App\Http\Controllers\Business\Pages;
+use ReflectionMethod;
+use Tests\TestCase;
+
+class PerformanceDifferenceRemarkTest extends TestCase
+{
+    private function remark(array $attributes): ?string
+    {
+        $row = (object) array_merge([
+            'platform' => '拼多多',
+            'match_status' => '已匹配',
+            'income_amount' => 0,
+            'discount_amount' => 0,
+            'offset_amount' => 0,
+            'refund_amount' => 0,
+            'product_amount' => 0,
+            'paid_amount' => 0,
+            'difference' => 0,
+            'planting_amount' => null,
+            'remark' => null,
+        ], $attributes);
+
+        return (new ReflectionMethod(Pages::class, 'receiptDifferenceRemark'))->invoke(null, $row);
+    }
+
+    public function test_pinduoduo_full_refund_wins_before_other_difference_rules(): void
+    {
+        $this->assertSame('订单实付含已退款部分', $this->remark([
+            'income_amount' => 7.00,
+            'discount_amount' => 17.00,
+            'refund_amount' => -7.00,
+            'product_amount' => 42.00,
+            'paid_amount' => 6.99,
+            'difference' => 17.01,
+        ]));
+    }
+
+    public function test_pinduoduo_partial_refund_marks_platform_payment_discount(): void
+    {
+        $this->assertSame('差额=平台支付立减', $this->remark([
+            'income_amount' => 896.00,
+            'refund_amount' => -552.36,
+            'product_amount' => 936.00,
+            'paid_amount' => 894.21,
+            'difference' => 1.79,
+        ]));
+
+        $this->assertSame('差额=平台支付立减', $this->remark([
+            'income_amount' => 16.43,
+            'refund_amount' => -12.00,
+            'product_amount' => 21.90,
+            'paid_amount' => 16.42,
+            'difference' => 0.01,
+        ]));
+    }
+
+    public function test_large_unexplained_pinduoduo_difference_stays_pending(): void
+    {
+        $this->assertSame('差额待核实', $this->remark([
+            'income_amount' => 130.00,
+            'refund_amount' => -50.00,
+            'product_amount' => 150.00,
+            'paid_amount' => 100.00,
+            'difference' => 30.00,
+        ]));
+    }
+}