diff --git a/README.md b/README.md
index 3f35a6bc..245c3948 100644
--- a/README.md
+++ b/README.md
@@ -93,8 +93,9 @@ This high-level architecture demonstrates how Marketing Analytics Jumpstart inte
 - [ ] [Create GCP project](https://cloud.google.com/resource-manager/docs/creating-managing-projects#creating_a_project) and [Enable Billing](https://cloud.google.com/billing/docs/how-to/modify-project)
 - [ ] Set up [Google Analyics 4 Export](https://support.google.com/analytics/answer/9823238?hl=en#zippy=%2Cin-this-article) and [Google Ads Export](https://cloud.google.com/bigquery/docs/google-ads-transfer) to Bigquery
 - [ ] [Backfill](https://cloud.google.com/bigquery/docs/google-ads-transfer) BigQuery Data Transfer service for Google Ads
-- [ ] Have existing Google Analytics 4 property with [Measurement ID](https://support.google.com/analytics/answer/12270356?hl=en)
+- [ ] Have existing Google Analytics 4 Property with [Measurement ID](https://support.google.com/analytics/answer/12270356?hl=en)
 
+**Note:** Google Ads Customer Matching currently only works with Google Analytics 4 **Properties** linked to Google Ads Accounts, it won't work for subproperties or Rollup properties.
 
 ## Installation Permissions and Privileges
 - [ ] Google Analytics Property Editor or Owner