diff --git a/scripts/backfill-phone-e164.ts b/scripts/backfill-phone-e164.ts
new file mode 100644
index 0000000..a737d08
--- /dev/null
+++ b/scripts/backfill-phone-e164.ts
@@ -0,0 +1,144 @@
+/**
+ * Backfill `client_contacts.value_e164` from `value` for phone / whatsapp
+ * contacts where it's null or empty.
+ *
+ * The legacy seed (and pre-normalization production data) stored phone
+ * numbers in `value` as free text — "+33 4 93 00 0002" — but `value_e164`
+ * is what every UI surface and dedup matcher reads. This script runs the
+ * raw `value` through libphonenumber-js (via the script-safe wrapper to
+ * avoid the Node 25 metadata-loader bug) and writes the canonical E.164
+ * form back.
+ *
+ * Usage:
+ *   pnpm tsx scripts/backfill-phone-e164.ts            # dry-run report
+ *   pnpm tsx scripts/backfill-phone-e164.ts --apply    # actually write
+ *
+ * The dry-run report prints, for each unparseable row, the contact id +
+ * raw value so you can hand-clean before re-running.
+ */
+import 'dotenv/config';
+import { and, eq, inArray, isNull, or, sql } from 'drizzle-orm';
+
+import { db } from '@/lib/db';
+import { clientContacts } from '@/lib/db/schema/clients';
+import { parsePhoneScriptSafe } from '@/lib/dedup/phone-parse';
+import type { CountryCode } from '@/lib/i18n/countries';
+
+const APPLY = process.argv.includes('--apply');
+
+interface PhoneRow {
+  id: string;
+  channel: string;
+  value: string | null;
+  valueCountry: string | null;
+}
+
+async function main() {
+  console.log(`Phone E.164 backfill — ${APPLY ? 'APPLY MODE' : 'dry-run'}`);
+  console.log('');
+
+  // Find candidate rows: phone or whatsapp contacts with a `value` set but
+  // `value_e164` null/empty.
+  const rows: PhoneRow[] = await db
+    .select({
+      id: clientContacts.id,
+      channel: clientContacts.channel,
+      value: clientContacts.value,
+      valueCountry: clientContacts.valueCountry,
+    })
+    .from(clientContacts)
+    .where(
+      and(
+        inArray(clientContacts.channel, ['phone', 'whatsapp']),
+        or(isNull(clientContacts.valueE164), eq(clientContacts.valueE164, '')),
+        sql`${clientContacts.value} IS NOT NULL AND ${clientContacts.value} <> ''`,
+      ),
+    );
+
+  console.log(`  found ${rows.length} candidate rows`);
+
+  let parsedFull = 0;
+  let parsedE164Only = 0;
+  let unparseable = 0;
+  const updates: Array<{
+    id: string;
+    valueE164: string;
+    valueCountry: CountryCode | null;
+  }> = [];
+  const fails: Array<{ id: string; value: string; reason: string }> = [];
+
+  for (const row of rows) {
+    if (!row.value) continue;
+    const defaultCountry = (row.valueCountry as CountryCode | null) ?? undefined;
+    const parsed1 = parsePhoneScriptSafe(row.value, defaultCountry);
+
+    if (parsed1.e164 && parsed1.country) {
+      // Both e164 + country resolved — best case.
+      updates.push({ id: row.id, valueE164: parsed1.e164, valueCountry: parsed1.country });
+      parsedFull++;
+    } else if (parsed1.e164) {
+      // E.164 came back but country didn't (e.g. UK +44 7700 900xxx
+      // fictional/reserved range — libphonenumber returns the e164 form
+      // but refuses to assign a country). Still safe to write — the e164
+      // is canonical. Country stays null.
+      updates.push({
+        id: row.id,
+        valueE164: parsed1.e164,
+        valueCountry: (row.valueCountry as CountryCode | null) ?? null,
+      });
+      parsedE164Only++;
+    } else {
+      fails.push({
+        id: row.id,
+        value: row.value,
+        reason: row.value.trim().startsWith('+')
+          ? 'has + prefix but parse failed'
+          : 'no leading + and no country hint',
+      });
+      unparseable++;
+    }
+  }
+
+  console.log('');
+  console.log('  ✓ parsed cleanly (e164 + country)', parsedFull);
+  console.log('  ✓ parsed e164 only (no country) ', parsedE164Only);
+  console.log('  ✗ unparseable                   ', unparseable);
+  console.log('');
+
+  if (fails.length > 0) {
+    console.log('Failures (first 10):');
+    for (const f of fails.slice(0, 10)) {
+      console.log(`  [${f.id}] "${f.value}" — ${f.reason}`);
+    }
+    console.log('');
+  }
+
+  if (!APPLY) {
+    console.log('Dry-run only. Re-run with --apply to write the updates.');
+    return;
+  }
+
+  if (updates.length === 0) {
+    console.log('No updates to write.');
+    return;
+  }
+
+  console.log(`Writing ${updates.length} updates...`);
+
+  for (const u of updates) {
+    await db
+      .update(clientContacts)
+      .set({
+        valueE164: u.valueE164,
+        valueCountry: u.valueCountry,
+      })
+      .where(eq(clientContacts.id, u.id));
+  }
+
+  console.log(`  ✓ wrote ${updates.length} rows`);
+}
+
+main().catch((err) => {
+  console.error(err);
+  process.exit(1);
+});