diff --git a/nexa_coa_setup/scripts/convert_l10nca_to_4digit.py b/nexa_coa_setup/scripts/convert_l10nca_to_4digit.py
new file mode 100644
index 00000000..811f327a
--- /dev/null
+++ b/nexa_coa_setup/scripts/convert_l10nca_to_4digit.py
@@ -0,0 +1,34 @@
+"""Rename the l10n_ca bank/AR/AP/tax legacy accounts to 4-digit codes."""
+LEGACY_MAP = [
+    # (old_code, new_code, expected_name_substring)
+    ("112005", "1010", "Scotia Current"),       # Primary operating (most-used)
+    ("112004", "1030", "BMO"),                   # BMO bank
+    ("112007", "1040", "RBC"),                   # RBC bank (NOT visa)
+    ("112008", "1070", "Scotia Credit Card"),    # Scotia CC
+    ("112006", "1071", "RBC VISA"),              # RBC visa
+    ("112002", "1080", "Outstanding Receipts"),  # In-transit receipts
+    ("112003", "1081", "Outstanding Payments"),  # In-transit payments
+    ("112001", "1090", "Bank Suspense"),         # Catch-all suspense
+    ("115100", "1100", "Customers Account"),     # AR control
+    ("118310", "1215", "HST receivable - 13%"),  # Legacy 13% HST receivable (near new 1210)
+    ("211100", "2010", "Vendors Account"),       # AP control
+    ("213310", "2115", "HST to pay - 13%"),      # Legacy 13% HST collected (near new 2110)
+]
+ok = 0; skipped = 0; missing = 0
+for old, new, hint in LEGACY_MAP:
+    acc = env['account.account'].search([('code', '=', old)], limit=1)
+    if not acc:
+        print(f"MISS {old} -> {new}: not found")
+        missing += 1; continue
+    if hint.lower() not in (acc.name or '').lower():
+        print(f"SKIP {old} -> {new}: name '{acc.name}' doesn't match '{hint}'")
+        skipped += 1; continue
+    conflict = env['account.account'].with_context(active_test=False).search([('code', '=', new)], limit=1)
+    if conflict:
+        print(f"SKIP {old} -> {new}: target occupied by {conflict.name}")
+        skipped += 1; continue
+    acc.code = new
+    ok += 1
+    print(f"OK {old} -> {new}: {acc.name}")
+print(f">>> Renumbered {ok}, skipped {skipped}, missing {missing} of {len(LEGACY_MAP)}")
+env.cr.commit()