diff --git a/api/src/billing/billing.service.spec.ts b/api/src/billing/billing.service.spec.ts
index e082d79..2778902 100644
--- a/api/src/billing/billing.service.spec.ts
+++ b/api/src/billing/billing.service.spec.ts
@@ -11,7 +11,7 @@ function createPrismaMock() {
       findMany: jest.fn().mockResolvedValue([]),
     },
     tenantAccount: {
-      findMany: jest.fn(),
+      findMany: jest.fn().mockResolvedValue([]),
       findUnique: jest.fn().mockImplementation(() => Promise.resolve({ ...accountState })),
       findUniqueOrThrow: jest.fn().mockImplementation(() => Promise.resolve({ ...accountState })),
       create: jest.fn(),
@@ -30,7 +30,7 @@ function createPrismaMock() {
       }),
     },
     accountTransaction: {
-      findMany: jest.fn(),
+      findMany: jest.fn().mockResolvedValue([]),
       findFirst: jest.fn(),
       findUnique: jest.fn().mockResolvedValue(null),
       findUniqueOrThrow: jest.fn().mockImplementation(({ where }) => Promise.resolve({ id: 'tx-charged', idempotencyKey: where.idempotencyKey })),
@@ -55,6 +55,7 @@ function createPrismaMock() {
       create: jest.fn().mockResolvedValue({ id: 'operation-1' }),
     },
     $executeRaw: jest.fn(),
+    $queryRaw: jest.fn(),
   };
   return Object.assign(prisma, {
     $transaction: jest.fn((callback: (client: typeof prisma) => unknown) => callback(prisma)),
@@ -319,11 +320,11 @@ describe('BillingService', () => {
   it('settles a frozen SMS charge with one account lock and an idempotent ledger pair', async () => {
     const prisma = createPrismaMock();
     const rows = new Map<string, Record<string, unknown>>();
-    prisma.accountTransaction.findUnique.mockImplementation(({ where }) => Promise.resolve(rows.get(where.idempotencyKey) ?? null));
-    prisma.accountTransaction.findUniqueOrThrow.mockImplementation(({ where }) => Promise.resolve(rows.get(where.idempotencyKey)));
-    prisma.accountTransaction.createMany.mockImplementation(({ data }) => {
-      data.forEach((row: Record<string, unknown>) => rows.set(String(row.idempotencyKey), { id: `tx-${row.transactionType}`, ...row }));
-      return Promise.resolve({ count: data.length });
+    prisma.accountTransaction.findMany.mockImplementation(() => Promise.resolve([...rows.values()]));
+    prisma.$queryRaw.mockImplementation(() => {
+      const charged = { id: 'tx-charged', idempotencyKey: 'sms-charge:msg-paid-1', transactionType: 'charged', amountCents: -325 };
+      rows.set(String(charged.idempotencyKey), charged);
+      return Promise.resolve([charged]);
     });
     const service = new BillingService(prisma as never);
     const input = { tenantId: 'tenant-1', amountCents: 325, messageId: 'msg-paid-1', taskId: 'task-paid-1' };
@@ -333,7 +334,8 @@ describe('BillingService', () => {
 
     expect(first).toEqual(expect.objectContaining({ transactionType: 'charged', amountCents: -325 }));
     expect(replay).toEqual(first);
-    expect(prisma.accountTransaction.createMany).toHaveBeenCalledTimes(1);
+    expect(prisma.$queryRaw).toHaveBeenCalledTimes(1);
+    expect(prisma.$executeRaw).not.toHaveBeenCalled();
     expect(prisma.tenantAccount.update).not.toHaveBeenCalled();
   });
 
diff --git a/api/src/billing/billing.service.ts b/api/src/billing/billing.service.ts
index 732c928..5a7d738 100644
--- a/api/src/billing/billing.service.ts
+++ b/api/src/billing/billing.service.ts
@@ -441,44 +441,49 @@ export class BillingService {
     if (amountCents <= 0) return null;
     const releaseKey = `sms-charge-release:${data.messageId}`;
     const chargeKey = `sms-charge:${data.messageId}`;
-    return this.prisma.$transaction(async (tx) => {
-      await tx.$executeRaw`SELECT pg_advisory_xact_lock(hashtextextended(${'tenant-account:' + data.tenantId}, 0))`;
-      const [release, charge] = await Promise.all([
-        tx.accountTransaction.findUnique({ where: { idempotencyKey: releaseKey } }),
-        tx.accountTransaction.findUnique({ where: { idempotencyKey: chargeKey } }),
-      ]);
-      if (charge) return charge;
-      const account = await tx.tenantAccount.findUniqueOrThrow({ where: { tenantId: data.tenantId } });
-      const balance = moneyToNumber(account.balanceCents);
-      if (release) {
-        const updated = await tx.tenantAccount.update({
-          where: { tenantId: data.tenantId },
-          data: { balanceCents: { decrement: amountCents } },
-        });
-        return tx.accountTransaction.create({
-          data: {
-            tenantId: data.tenantId, transactionType: 'charged', idempotencyKey: chargeKey,
-            amountCents: -amountCents, balanceAfter: updated.balanceCents,
-            relatedType: 'sms_message_record', relatedId: data.messageId, remark: '提交成功扣费',
-          },
-        });
-      }
-      await tx.accountTransaction.createMany({
-        data: [
-          {
-            tenantId: data.tenantId, transactionType: 'released', idempotencyKey: releaseKey,
-            amountCents, balanceAfter: balance + amountCents,
-            relatedType: 'sms_batch_task', relatedId: data.taskId, remark: data.remark,
-          },
-          {
-            tenantId: data.tenantId, transactionType: 'charged', idempotencyKey: chargeKey,
-            amountCents: -amountCents, balanceAfter: balance,
-            relatedType: 'sms_message_record', relatedId: data.messageId, remark: '提交成功扣费',
-          },
-        ],
+    const existing = await this.prisma.accountTransaction.findMany({
+      where: { idempotencyKey: { in: [releaseKey, chargeKey] } },
+    });
+    const charge = existing.find((row) => row.idempotencyKey === chargeKey);
+    if (charge) return charge;
+    const release = existing.find((row) => row.idempotencyKey === releaseKey);
+    if (release) {
+      // Recover the legacy two-transaction boundary: a crash may have committed
+      // release before charge, so this path must perform the missing balance debit.
+      return this.applyAccountDelta({
+        tenantId: data.tenantId, transactionType: 'charged', idempotencyKey: chargeKey,
+        amountCents: -amountCents, relatedType: 'sms_message_record', relatedId: data.messageId,
+        remark: '提交成功扣费（恢复既有已释放冻结）',
       });
-      return tx.accountTransaction.findUniqueOrThrow({ where: { idempotencyKey: chargeKey } });
-    }, { isolationLevel: Prisma.TransactionIsolationLevel.ReadCommitted });
+    }
+    const rows = await this.prisma.$queryRaw<Array<{ id: string; idempotencyKey: string }>>(Prisma.sql`
+      WITH account AS (
+        SELECT "balanceCents" FROM "TenantAccount" WHERE "tenantId" = ${data.tenantId}
+      ), inserted AS (
+        INSERT INTO "AccountTransaction" (
+          id, "tenantId", "transactionType", "idempotencyKey", "amountCents",
+          "balanceAfter", "relatedType", "relatedId", remark, "createdAt"
+        )
+        SELECT gen_random_uuid()::text, ${data.tenantId}, ledger."transactionType", ledger."idempotencyKey",
+               ledger."amountCents", account."balanceCents" + ledger."balanceDelta",
+               ledger."relatedType", ledger."relatedId", ledger.remark, (NOW() AT TIME ZONE 'UTC')
+        FROM account
+        CROSS JOIN (VALUES
+          ('released', ${releaseKey}, ${amountCents}::bigint, ${amountCents}::bigint, 'sms_batch_task', ${data.taskId}, ${data.remark ?? null}),
+          ('charged', ${chargeKey}, ${-amountCents}::bigint, 0::bigint, 'sms_message_record', ${data.messageId}, '提交成功扣费')
+        ) AS ledger("transactionType", "idempotencyKey", "amountCents", "balanceDelta", "relatedType", "relatedId", remark)
+        ON CONFLICT ("idempotencyKey") DO NOTHING
+        RETURNING id, "idempotencyKey"
+      )
+      SELECT id, "idempotencyKey" FROM inserted WHERE "idempotencyKey" = ${chargeKey}
+      UNION ALL
+      SELECT id, "idempotencyKey" FROM "AccountTransaction" WHERE "idempotencyKey" = ${chargeKey}
+      LIMIT 1
+    `);
+    if (rows[0]) return rows[0];
+    // A concurrent identical callback can win ON CONFLICT while remaining
+    // invisible to this statement's snapshot; one read repairs that MVCC edge.
+    return this.prisma.accountTransaction.findUniqueOrThrow({ where: { idempotencyKey: chargeKey } });
   }
 
   release(data: BillingActionDto) {
diff --git a/docs/codebase-modularization-roadmap.md b/docs/codebase-modularization-roadmap.md
index c634ff5..499f44a 100644
--- a/docs/codebase-modularization-roadmap.md
+++ b/docs/codebase-modularization-roadmap.md
@@ -1168,6 +1168,6 @@ global，不能错误归入client。`client-signature-*`、发送页、企业认
 ## 2026-08-21 第四阶段模块边界
 
 - `send-inbound-entry`负责编排正价批次短事务；账户固定锁序、总额覆盖、逐短信冻结幂等键留在PostgreSQL一致性边界，不迁入Redis。
-- `billing.service`集中维护账户锁和流水，`settleFrozenCharge`把释放/扣费合并为一个事务；`send-accounting`只编排消息计费状态。
+- `billing.service`集中维护余额锁和流水；`settleFrozenCharge`利用冻结已完成扣减、释放与扣费净变化为零的事实，以单个幂等SQL写成流水对且不争抢账户锁，只有历史半完成恢复才进入带锁余额补扣；`send-accounting`只编排消息计费状态。
 - `send-chain.helpers`提供无副作用的优先级、主备和稳定weight选择；提交服务只提供消息稳定键与真实在线/报备候选，不保存进程内轮询状态。
 - Gateway既有Submit池与结果Outbox继续独立有界；先以正价六通道实测定位容量，只有证据证明单条回调仍触发停止线时才扩展批量回调协议。
diff --git a/docs/first-version-development-requirements.md b/docs/first-version-development-requirements.md
index a0b5b31..cc0224d 100644
--- a/docs/first-version-development-requirements.md
+++ b/docs/first-version-development-requirements.md
@@ -2133,6 +2133,6 @@
 ## 完整处理500条/秒第四阶段：正价计费与供应商并行（2026-08-21）
 
 - 普通CMPP短短信批量路径必须支持正单价：按企业固定锁序一次校验批次总金额、一次更新余额，并为每短信写独立幂等冻结流水；任务、请求、消息与冻结流水同属一个短事务。余额加授信必须覆盖所需金额，不能只判断大于零。
-- 供应商接受后，释放冻结与正式扣费在一个账户锁事务内保留两条审计流水；零金额不创建AccountTransaction。拒绝、超时、重投和最终失败继续沿用逐短信幂等释放、扣费和退款。
+- 供应商接受后，释放冻结与正式扣费以一个原子SQL写入两条幂等审计流水；二者净余额变化为零，不得争抢企业账户锁或重复更新账户。只有恢复历史“已释放但未扣费”半完成状态时才取得账户锁补扣。零金额不创建AccountTransaction；拒绝、超时、重投和最终失败继续沿用逐短信幂等释放、扣费和退款。
 - 同通道组内在线、已报备、同地域、同最低优先级且非备用的通道按weight和稳定消息键分流；备用、离线及更低优先级不抢占。只有显式配置为同优先级非备用的通道才参与主动双活。
 - 压测使用隔离测试企业、真实PostgreSQL账务、单价`0.0325元/计费条`、三运营商混合号码和六个模拟供应商账号；逐档核对消息、冻结/释放/扣费/退款、SmsBillingRecord、通道分布、队列和数据库。临时单价与主动双活配置须先快照、测试后恢复。
diff --git a/docs/system-functional-test-cases.md b/docs/system-functional-test-cases.md
index 91bd650..6f25e24 100644
--- a/docs/system-functional-test-cases.md
+++ b/docs/system-functional-test-cases.md
@@ -4779,7 +4779,7 @@ npm run verify:phase8
 | --- | --- | --- |
 | TC-CMPP-500-P4-001 | 同企业正价短短信批量入站并重放 | 一次账户余额更新；每短信唯一`:freeze`流水；任务/请求/消息金额正确；重放不重复冻结 |
 | TC-CMPP-500-P4-002 | 余额加授信小于批次或单条金额 | 不得透支；批次安全回退且只发送余额覆盖的短信 |
-| TC-CMPP-500-P4-003 | 正价短信Submit接受及Outbox重放 | 一个账户锁事务生成released/charged；余额净值不重复变化；SmsBillingRecord唯一charged |
+| TC-CMPP-500-P4-003 | 正价短信Submit接受及Outbox重放 | 一个原子SQL生成released/charged且不取得账户锁；余额净值不重复变化；SmsBillingRecord唯一charged；历史半完成状态仍可锁定恢复 |
 | TC-CMPP-500-P4-004 | 零价短信Submit接受 | 保留业务结果但无0金额AccountTransaction |
 | TC-CMPP-500-P4-005 | 两个同优先级非备用通道与一个备用通道 | 稳定weighted分流只覆盖两个主动通道；排除已尝试通道后可安全切换；备用不抢占 |
 | TC-CMPP-500-P4-006 | 三运营商、六通道、325金额单位阶梯压测 | 每档入口/Inbox/供应商/回执/账务对账一致，双Stream和数据库最终稳定排空；失败即停止升档 |
diff --git a/docs/testing-progress.md b/docs/testing-progress.md
index a020a3f..606cd88 100644
--- a/docs/testing-progress.md
+++ b/docs/testing-progress.md
@@ -3840,3 +3840,6 @@ git diff --check
 - 10个隔离应用仍为单价0、同企业余额1/授信0；移动主备各200条/秒，联通/电信主备各150条/秒，窗口32。组项目为主10/备用20，默认只能三主主动承载，六连接在线不等于六通道并行。
 - 已实现正价Worker批次、覆盖本次金额的余额判断、单事务释放/扣费、零价免账户流水，以及同最低优先级非备用通道的稳定weighted分流；默认主备语义不变。API正式编译和Billing/纯策略/SendChain三套143项通过。
 - 部署、恢复资产、测试充值、临时六通道主动双活、smoke及阶梯结果待补记；所有临时配置只允许在测试环境先快照后变更并在测试后恢复。
+- 首轮正价三运营商100条/秒生成2999条，2999/2999 SubmitResp成功、P50/P95/P99=`32/68/130ms`，Inbox与唯一MessageId均2999；移动/联通/电信分别998/996/1005，六通道最终各承载488至514条，证明主动双活与跨运营商分流有效。注入结束时仅388条完成扣费，命令Stream`128/2131`、结果Outbox`32/192`、等待锁/idle in transaction各5，按停止线不升200档。
+- 该轮最终双Stream归零，冻结/释放各2999、正式扣费2987、退款30、12条供应商最终拒绝只释放不扣费；SmsBillingRecord为charged2957/refunded30，余额恒等式精确成立，六通道与数据库最终无等待锁/idle in transaction。证据确认瓶颈是每个正价Submit结果在企业账户锁上串行，而不是单价0时可见的通道容量。
+- 后续最小修复将正常“释放冻结+正式扣费”改为单个幂等SQL：冻结已在入口扣减，流水对净余额为零，因此正常结算不再取得账户锁或更新账户；历史已释放未扣费状态仍用原带锁路径补扣，并保留并发`ON CONFLICT`后一次MVCC恢复读。专项134项和TypeScript已通过，完整门禁、修复提交、新恢复资产与复测待补记。