diff --git a/internal/model/testdb.go b/internal/model/testdb.go
index 4910b80..e12d7f3 100644
--- a/internal/model/testdb.go
+++ b/internal/model/testdb.go
@@ -32,7 +32,7 @@ func OpenTestDB(t *testing.T) *gorm.DB {
 		t.Fatalf("open test db: %v", err)
 	}
 	if err := db.AutoMigrate(&OrderV2{}, &Attempt{}, &Account{}, &Refund{}, &WebhookDelivery{},
-		&Product{}, &ProductPrice{}); err != nil {
+		&Product{}, &ProductPrice{}, &Subscription{}); err != nil {
 		t.Fatalf("migrate: %v", err)
 	}
 	if err := UpgradeWebhookDeliveryIndex(db); err != nil {
diff --git a/internal/model/v2.go b/internal/model/v2.go
index 94665b0..f5f4dcc 100644
--- a/internal/model/v2.go
+++ b/internal/model/v2.go
@@ -121,3 +121,33 @@ type Refund struct {
 	InitiatedBy        string       `gorm:"size:16"` // business/platform
 	CompletedAt        *time.Time
 }
+
+// ---- 订阅(recurring)----
+
+type SubStatus string
+
+const (
+	SubActive   SubStatus = "active"   // 已激活,正常续费
+	SubPastDue  SubStatus = "past_due" // 某期扣款失败,待恢复(invoice.payment_failed)
+	SubCanceled SubStatus = "canceled" // 已取消(主动/网关删除),终态
+)
+
+// Subscription 是"同一 entitlement 的跨期账本"(设计 §5.1)。单笔层(OrderV2/Attempt)
+// 与订阅层解耦:每期扣款仍落一张 renewal OrderV2,Subscription 只维护状态机 + 续费锚点。
+type Subscription struct {
+	Base
+	SubID            string    `gorm:"uniqueIndex;size:64;not null"` // pay 生成的逻辑订阅号
+	OutTradeNo       string    `gorm:"index;size:64;not null"`       // 首购 order(诞生订阅那笔)
+	MerchantID       uint64    `gorm:"index"`
+	BizSystem        string    `gorm:"index;size:32"`
+	BizRef           string    `gorm:"size:128"`
+	BizCode          string    `gorm:"index;size:64"` // 套餐码副本,续费事件带回
+	Channel          string    `gorm:"index;size:32;not null;uniqueIndex:uq_sub_provider"`
+	ProviderSubRef   string    `gorm:"size:128;not null;uniqueIndex:uq_sub_provider"` // 渠道订阅号(stripe sub id)
+	RecurringKind    string    `gorm:"size:24"`                                       // gateway_scheduled/token_offsession/...
+	AmountMinor      int64     `gorm:"not null"`
+	Currency         string    `gorm:"size:16;not null"`
+	Status           SubStatus `gorm:"index;size:16;not null"`
+	CurrentPeriodEnd *time.Time
+	CanceledAt       *time.Time
+}
diff --git a/internal/store/subscription.go b/internal/store/subscription.go
new file mode 100644
index 0000000..0ba7822
--- /dev/null
+++ b/internal/store/subscription.go
@@ -0,0 +1,87 @@
+package store
+
+import (
+	"errors"
+	"fmt"
+	"time"
+
+	"gorm.io/gorm"
+	"gorm.io/gorm/clause"
+
+	"github.com/wangjia/pay/internal/model"
+)
+
+var ErrSubNotFound = errors.New("store: subscription not found")
+
+type SubscriptionStore struct{ db *gorm.DB }
+
+func NewSubscriptionStore(db *gorm.DB) *SubscriptionStore { return &SubscriptionStore{db: db} }
+
+// Create 幂等插入:重复 (channel,provider_sub_ref) → no-op(created=false)。
+// Stripe 会重投 checkout.session.completed;诞生订阅必须幂等。
+func (s *SubscriptionStore) Create(sub *model.Subscription) (bool, error) {
+	res := s.db.Clauses(clause.OnConflict{
+		Columns:   []clause.Column{{Name: "channel"}, {Name: "provider_sub_ref"}},
+		DoNothing: true,
+	}).Create(sub)
+	if res.Error != nil {
+		return false, fmt.Errorf("store.SubscriptionStore.Create: %w", res.Error)
+	}
+	return res.RowsAffected > 0, nil
+}
+
+func (s *SubscriptionStore) GetBySubID(subID string) (*model.Subscription, error) {
+	var sub model.Subscription
+	if err := s.db.Where("sub_id = ?", subID).First(&sub).Error; err != nil {
+		if errors.Is(err, gorm.ErrRecordNotFound) {
+			return nil, ErrSubNotFound
+		}
+		return nil, fmt.Errorf("store.GetBySubID: %w", err)
+	}
+	return &sub, nil
+}
+
+func (s *SubscriptionStore) GetByProviderRef(channel, ref string) (*model.Subscription, error) {
+	var sub model.Subscription
+	if err := s.db.Where("channel = ? AND provider_sub_ref = ?", channel, ref).First(&sub).Error; err != nil {
+		if errors.Is(err, gorm.ErrRecordNotFound) {
+			return nil, ErrSubNotFound
+		}
+		return nil, fmt.Errorf("store.GetByProviderRef: %w", err)
+	}
+	return &sub, nil
+}
+
+// Activate 置 active + 刷新续费锚点(past_due 续费成功恢复也走它);canceled 终态不复活。
+func (s *SubscriptionStore) Activate(subID string, periodEnd *time.Time) (bool, error) {
+	upd := map[string]any{"status": model.SubActive}
+	if periodEnd != nil {
+		upd["current_period_end"] = periodEnd
+	}
+	res := s.db.Model(&model.Subscription{}).
+		Where("sub_id = ? AND status <> ?", subID, model.SubCanceled).Updates(upd)
+	if res.Error != nil {
+		return false, fmt.Errorf("store.Activate: %w", res.Error)
+	}
+	return res.RowsAffected > 0, nil
+}
+
+func (s *SubscriptionStore) MarkPastDue(channel, providerRef string) (bool, error) {
+	res := s.db.Model(&model.Subscription{}).
+		Where("channel = ? AND provider_sub_ref = ? AND status = ?", channel, providerRef, model.SubActive).
+		Update("status", model.SubPastDue)
+	if res.Error != nil {
+		return false, fmt.Errorf("store.MarkPastDue: %w", res.Error)
+	}
+	return res.RowsAffected > 0, nil
+}
+
+func (s *SubscriptionStore) MarkCanceled(subID string) (bool, error) {
+	res := s.db.Model(&model.Subscription{}).
+		Where("sub_id = ? AND status <> ?", subID, model.SubCanceled).
+		Updates(map[string]any{"status": model.SubCanceled, "canceled_at": time.Now()})
+	if res.Error != nil {
+		return false, fmt.Errorf("store.MarkCanceled: %w", res.Error)
+	}
+	return res.RowsAffected > 0, nil
+}
diff --git a/internal/store/subscription_test.go b/internal/store/subscription_test.go
new file mode 100644
index 0000000..22dc9c1
--- /dev/null
+++ b/internal/store/subscription_test.go
@@ -0,0 +1,65 @@
+package store_test
+
+import (
+	"testing"
+	"time"
+
+	"github.com/wangjia/pay/internal/model"
+	"github.com/wangjia/pay/internal/store"
+)
+
+func newSubStore(t *testing.T) *store.SubscriptionStore {
+	return store.NewSubscriptionStore(model.OpenTestDB(t))
+}
+
+func TestSubscriptionCreateIdempotent(t *testing.T) {
+	s := newSubStore(t)
+	sub := &model.Subscription{SubID: "SUB-1", Channel: "stripe", ProviderSubRef: "sub_x",
+		OutTradeNo: "PAY-1", BizSystem: "pangolin", BizRef: "u-1", BizCode: "pro_month",
+		AmountMinor: 2999, Currency: "USD", Status: model.SubActive}
+	created, err := s.Create(sub)
+	if err != nil || !created {
+		t.Fatalf("first create: created=%v err=%v", created, err)
+	}
+	// 同 provider_sub_ref 再建 → 幂等 no-op(Stripe 重投 checkout.completed)
+	again, err := s.Create(&model.Subscription{SubID: "SUB-2", Channel: "stripe", ProviderSubRef: "sub_x",
+		OutTradeNo: "PAY-1", AmountMinor: 2999, Currency: "USD", Status: model.SubActive})
+	if err != nil || again {
+		t.Fatalf("dup create: again=%v err=%v", again, err)
+	}
+}
+
+func TestSubscriptionStateMachine(t *testing.T) {
+	s := newSubStore(t)
+	end := time.Now().Add(30 * 24 * time.Hour)
+	if _, err := s.Create(&model.Subscription{SubID: "SUB-9", Channel: "stripe", ProviderSubRef: "sub_9",
+		OutTradeNo: "PAY-9", AmountMinor: 2999, Currency: "USD", Status: model.SubActive}); err != nil {
+		t.Fatal(err)
+	}
+	// active → past_due
+	ok, _ := s.MarkPastDue("stripe", "sub_9")
+	if !ok {
+		t.Fatal("MarkPastDue should flip active→past_due")
+	}
+	// past_due → active(续费恢复)
+	ok, _ = s.Activate("SUB-9", &end)
+	if !ok {
+		t.Fatal("Activate should recover past_due→active")
+	}
+	// → canceled(终态)
+	ok, _ = s.MarkCanceled("SUB-9")
+	if !ok {
+		t.Fatal("MarkCanceled should flip →canceled")
+	}
+	// canceled 后不可复活
+	if ok, _ := s.Activate("SUB-9", &end); ok {
+		t.Fatal("canceled sub must not be re-activated")
+	}
+	if ok, _ := s.MarkPastDue("stripe", "sub_9"); ok {
+		t.Fatal("canceled sub must not go past_due")
+	}
+	got, err := s.GetBySubID("SUB-9")
+	if err != nil || got.Status != model.SubCanceled {
+		t.Fatalf("final status = %v err=%v", got.Status, err)
+	}
+}
diff --git a/main.go b/main.go
index 8c039de..55fcf5d 100644
--- a/main.go
+++ b/main.go
@@ -122,6 +122,7 @@ func autoMigrate(db *gorm.DB) {
 		&model.NotifyLog{},
 		&model.BizNotifyLog{},
 		&model.OrderV2{}, &model.Attempt{}, &model.Account{}, &model.Refund{}, &model.WebhookDelivery{}, // v2
+		&model.Subscription{}, // v2 recurring
 	); err != nil {
 		log.Fatalf("自动迁移失败: %v", err)
 	}