diff --git a/dbt_project.yml b/dbt_project.yml
index 718e56a..4a37fab 100644
--- a/dbt_project.yml
+++ b/dbt_project.yml
@@ -20,3 +20,7 @@ vars:
   # dbt_tags__policy_data_types: # optional, defaults to same policy name as tag name if not specified per policy
   #   - <tag-name>: ['datatype','list'] # list of tag names, assign list of datatypes. Suffixes policy name with datatypes on assigning policies to tags
   # dbt_tags__tag_name_separator: ~ # optional, the default value is tilda. If you use ~ in your tag names then you can set a different separator character here
+  # dbt_tags__tag_source_columns:  # Optional. Enables or disables the tagging of source columns.
+  #   When set to true, it allows the project to tag columns defined in sources.
+  #   By default, this project allows enabling column tagging when using the apply_column_tags() macro.
+  #   Set dbt_tags__tag_source_columns: false to disable source column tagging.
diff --git a/docs/index.md b/docs/index.md
index 300faee..c81b4bf 100644
--- a/docs/index.md
+++ b/docs/index.md
@@ -65,7 +65,7 @@ Here are the full list of built-in variables:
 - `dbt_tags__allowed_tags`
 - `dbt_tags__resource_types`
 - `dbt_tags__policy_data_types`
-
+- `dbt_tags__tag_source_columns`
 ## How to Contribute ❤️
 
 `dbt-tags` is an open-source dbt package. Whether you are a seasoned open-source contributor or a first-time committer, we welcome and encourage you to contribute code, documentation, ideas, or problem statements to this project.