diff --git a/scripts/reconcile-helcim-payments.mjs b/scripts/reconcile-helcim-payments.mjs
new file mode 100644
index 0000000..c047929
--- /dev/null
+++ b/scripts/reconcile-helcim-payments.mjs
@@ -0,0 +1,121 @@
+/**
+ * Reconcile Helcim transactions → Payment docs in Mongo.
+ *
+ * For every Member with a helcimCustomerId, fetch their recent Helcim
+ * transactions and upsert a Payment row for each one. Idempotent: existing
+ * Payment docs (keyed by helcimTransactionId) are never overwritten. Skips
+ * transactions with status 'other' (verify/auth-only etc.).
+ *
+ * Usage:
+ *   node scripts/reconcile-helcim-payments.mjs            # dry-run (default)
+ *   node scripts/reconcile-helcim-payments.mjs --apply    # writes new Payment rows
+ *
+ * Uses:
+ *   - Launch-day backfill for pre-existing members.
+ *   - Ongoing reconciliation (nightly cron) to catch Helcim-initiated recurring
+ *     charges that bypass the synchronous write paths in subscription.post.js
+ *     and update-contribution.post.js.
+ *
+ * Required env: MONGODB_URI, HELCIM_API_TOKEN
+ */
+
+import dotenv from 'dotenv'
+import { fileURLToPath } from 'url'
+import { dirname, resolve } from 'path'
+import mongoose from 'mongoose'
+
+const __filename = fileURLToPath(import.meta.url)
+const __dirname = dirname(__filename)
+dotenv.config({ path: resolve(__dirname, '../.env') })
+
+// Nitro auto-imports used inside server/utils/helcim.js — shim them so the
+// util module loads outside the Nitro runtime.
+globalThis.useRuntimeConfig = () => ({ helcimApiToken: process.env.HELCIM_API_TOKEN })
+globalThis.createError = (opts = {}) => {
+  const err = new Error(opts.statusMessage || 'Error')
+  Object.assign(err, opts)
+  return err
+}
+
+const { default: Member } = await import('../server/models/member.js')
+const { default: Payment } = await import('../server/models/payment.js')
+const { listHelcimCustomerTransactions } = await import('../server/utils/helcim.js')
+const { upsertPaymentFromHelcim } = await import('../server/utils/payments.js')
+
+async function run() {
+  const apply = process.argv.includes('--apply')
+
+  if (!process.env.MONGODB_URI) {
+    console.error('MONGODB_URI not set in environment')
+    process.exit(1)
+  }
+  if (!process.env.HELCIM_API_TOKEN) {
+    console.error('HELCIM_API_TOKEN not set in environment')
+    process.exit(1)
+  }
+
+  await mongoose.connect(process.env.MONGODB_URI)
+
+  const members = await Member.find(
+    { helcimCustomerId: { $exists: true, $ne: null } },
+    { _id: 1, email: 1, name: 1, helcimCustomerId: 1, helcimSubscriptionId: 1, billingCadence: 1 }
+  ).lean()
+
+  console.log(`Scanning ${members.length} members with helcimCustomerId`)
+
+  let txExamined = 0
+  let created = 0
+  let existed = 0
+  let skipped = 0
+  let memberErrors = 0
+
+  for (const member of members) {
+    let txs
+    try {
+      txs = await listHelcimCustomerTransactions(member.helcimCustomerId)
+    } catch (err) {
+      memberErrors++
+      console.error(`  ERR member=${member._id} (${member.email}): ${err?.message || err}`)
+      continue
+    }
+
+    for (const tx of txs) {
+      txExamined++
+      if (tx.status === 'other') {
+        skipped++
+        continue
+      }
+
+      if (!apply) {
+        const existing = await Payment.findOne({ helcimTransactionId: tx.id })
+        if (existing) existed++
+        else created++
+        continue
+      }
+
+      const result = await upsertPaymentFromHelcim(member, tx)
+      if (result.created) created++
+      else if (result.payment) existed++
+      else skipped++
+    }
+  }
+
+  const verb = apply ? 'Created' : 'Would create'
+  console.log(`\nMembers scanned: ${members.length}`)
+  console.log(`Transactions examined: ${txExamined}`)
+  console.log(`${verb}: ${created}`)
+  console.log(`Already existed: ${existed}`)
+  console.log(`Skipped (status=other or unmapped): ${skipped}`)
+  if (memberErrors > 0) console.log(`Helcim API errors for members: ${memberErrors}`)
+  if (!apply) console.log('\nDry-run complete. Re-run with --apply to write Payment rows.')
+
+  await mongoose.disconnect()
+}
+
+run().catch(async (err) => {
+  console.error(err)
+  try {
+    await mongoose.disconnect()
+  } catch {}
+  process.exit(1)
+})