diff --git a/next_crm/patches.txt b/next_crm/patches.txt
index c0ec8ad91c..d26d4b95d6 100644
--- a/next_crm/patches.txt
+++ b/next_crm/patches.txt
@@ -17,3 +17,4 @@ next_crm.patches.v1_0.update_won_date
 next_crm.patches.v1_0.update_crm_views_filters
 next_crm.patches.v1_0.add_contracts_documents_section_to_customers
 next_crm.patches.v0_1.remove_stale_field_order_property_setters
+next_crm.patches.v1_0.backfill_utm_source_from_legacy_source
diff --git a/next_crm/patches/v1_0/backfill_utm_source_from_legacy_source.py b/next_crm/patches/v1_0/backfill_utm_source_from_legacy_source.py
new file mode 100644
index 0000000000..701e0cc35b
--- /dev/null
+++ b/next_crm/patches/v1_0/backfill_utm_source_from_legacy_source.py
@@ -0,0 +1,75 @@
+"""Backfill `utm_source` from the legacy `source` column on Lead and Opportunity.
+
+Mirrors https://github.com/frappe/erpnext/pull/55022 — shipped here so sites
+running next_crm don't have to wait on the upstream patch landing.
+
+The v15 patch `erpnext.patches.v15_0.migrate_to_utm_analytics` migrated the
+`Lead Source` lookup doctype's rows into `UTM Source`, then renamed the
+per-row `source` field on Lead/Opportunity to `utm_source` via the
+`oldfieldname` schema hint.
+
+That hint is documentation-only in Frappe — the only code path that actually
+issues a `RENAME COLUMN` is the desk-driven Custom Field rename flow.
+Standard DocField schema-sync only adds new columns and modifies existing
+ones; it never renames or drops based on JSON changes. So on every site
+that ran the v15 patch, `utm_source` was added empty alongside the legacy
+`source` column, and every row's source value was orphaned on the now
+meta-less `source` column.
+
+This patch promotes those values: where `utm_source` is empty and the
+legacy `source` column still exists with a value, copy it forward. Rows
+where both columns are set to *different* values are left untouched and
+surfaced as a count for the operator to triage. Idempotent re-run is a
+no-op.
+"""
+
+import click
+import frappe
+from frappe.query_builder.functions import Count
+
+
+def execute():
+    for doctype in ("Lead", "Opportunity"):
+        if not frappe.db.exists("DocType", doctype):
+            continue
+        columns = frappe.db.get_table_columns(doctype)
+        if "source" not in columns or "utm_source" not in columns:
+            # Either the legacy column was already dropped (clean rename
+            # completed) or the new column never landed — nothing to do.
+            continue
+
+        _backfill_one(doctype)
+
+
+def _backfill_one(doctype: str) -> None:
+    table = frappe.qb.DocType(doctype)
+
+    empty_utm = table.utm_source.isnull() | (table.utm_source == "")
+    utm_set = table.utm_source.isnotnull() & (table.utm_source != "")
+    source_set = table.source.isnotnull() & (table.source != "")
+
+    to_fill = (
+        frappe.qb.from_(table).select(Count("*")).where(empty_utm & source_set).run()
+    )[0][0]
+    conflicts = (
+        frappe.qb.from_(table)
+        .select(Count("*"))
+        .where(utm_set & source_set & (table.utm_source != table.source))
+        .run()
+    )[0][0]
+
+    if to_fill:
+        frappe.qb.update(table).set(table.utm_source, table.source).where(
+            empty_utm & source_set
+        ).run()
+        click.secho(
+            f"  {doctype}: copied legacy `source` → `utm_source` on {to_fill} rows",
+            fg="green",
+        )
+
+    if conflicts:
+        click.secho(
+            f"  {doctype}: {conflicts} rows have both `source` and `utm_source` populated "
+            f"with DIFFERENT values; left untouched — review manually",
+            fg="yellow",
+        )