diff --git a/backend/scripts/check-beijing-social.ts b/backend/scripts/check-beijing-social.ts
new file mode 100644
index 0000000..9752a95
--- /dev/null
+++ b/backend/scripts/check-beijing-social.ts
@@ -0,0 +1,10 @@
+import { PrismaClient } from '@prisma/client'
+const prisma = new PrismaClient()
+async function main() {
+  const accounts = await prisma.socialAccount.findMany({ where: { type: 'SOCIAL', city: '北京' }, select: { id: true, name: true } })
+  for (const a of accounts) {
+    const std = await prisma.socialYearStandard.findFirst({ where: { accountId: a.id, isCurrent: true }, select: { medicalOrgExtra: true, medicalEmpExtra: true, extraInsurances: true, effectiveFrom: true } })
+    console.log(a.name + ' | effective=' + std?.effectiveFrom + ' | medicalOrgExtra=' + std?.medicalOrgExtra + ' | medicalEmpExtra=' + std?.medicalEmpExtra + ' | extraInsurances=' + JSON.stringify(std?.extraInsurances))
+  }
+}
+main().then(() => process.exit(0))
diff --git a/backend/scripts/fix-medical-extra.ts b/backend/scripts/fix-medical-extra.ts
new file mode 100644
index 0000000..24734b3
--- /dev/null
+++ b/backend/scripts/fix-medical-extra.ts
@@ -0,0 +1,25 @@
+/**
+ * 更新北京社保账户的大病医疗个人附加（3元/月）
+ */
+import { PrismaClient } from '@prisma/client'
+const prisma = new PrismaClient()
+
+async function main() {
+  // 北京社保账户：医疗个人附加3元（大病医疗）
+  const beijingSocial = await prisma.socialAccount.findMany({ where: { type: 'SOCIAL', city: '北京' }, select: { id: true, name: true } })
+  for (const a of beijingSocial) {
+    const result = await prisma.socialYearStandard.updateMany({
+      where: { accountId: a.id, isCurrent: true },
+      data: { medicalEmpExtra: 3 },
+    })
+    console.log(`[更新] ${a.name} → medicalEmpExtra=3，影响 ${result.count} 条`)
+  }
+
+  // 验证
+  for (const a of beijingSocial) {
+    const std = await prisma.socialYearStandard.findFirst({ where: { accountId: a.id, isCurrent: true }, select: { medicalEmpExtra: true, effectiveFrom: true } })
+    console.log(`[验证] ${a.name} | effective=${std?.effectiveFrom} | medicalEmpExtra=${std?.medicalEmpExtra}`)
+  }
+}
+
+main().then(() => process.exit(0)).catch(e => { console.error(e); process.exit(1) })
diff --git a/backend/src/routes/social.routes.ts b/backend/src/routes/social.routes.ts
index 760122f..7010471 100644
--- a/backend/src/routes/social.routes.ts
+++ b/backend/src/routes/social.routes.ts
@@ -263,6 +263,22 @@ router.post('/accounts/:accountId/standards', async (req: AuthRequest, res: Resp
     const account = await prisma.socialAccount.findFirst({ where: { id: accountId, orgId } })
     if (!account) return res.status(404).json({ success: false, error: { code: 'NOT_FOUND', message: '账户不存在' } })
 
+    // 检查是否已存在同 effectiveFrom 的标准
+    const existing = await prisma.socialYearStandard.findFirst({ where: { accountId, effectiveFrom: data.effectiveFrom } })
+    if (existing) {
+      // 已存在：更新而非报错
+      const standard = await prisma.socialYearStandard.update({
+        where: { id: existing.id },
+        data: { ...data, isCurrent: true, effectiveTo: null },
+      })
+      // 将其他当前版本标记为失效
+      await prisma.socialYearStandard.updateMany({
+        where: { accountId, isCurrent: true, id: { not: existing.id } },
+        data: { isCurrent: false, effectiveTo: data.effectiveFrom },
+      })
+      return res.json({ success: true, data: standard })
+    }
+
     // 将旧当前版本标记为失效
     const current = await prisma.socialYearStandard.findFirst({ where: { accountId, isCurrent: true } })
     if (current) {