diff --git a/data/reusables/repositories/repo-name.md b/data/reusables/repositories/repo-name.md
index 35dcdb76aeed..7c831e3120ea 100644
--- a/data/reusables/repositories/repo-name.md
+++ b/data/reusables/repositories/repo-name.md
@@ -1,3 +1,3 @@
-1. Type a name for your repository (maximum 100 characters), and an optional description.
+1. Type a name for your repository and an optional description. The repository name must not exceed 100 characters, and can only contain ASCII letters, digits, and the characters `.`, `-`, and `_`.
 
    ![Screenshot of a the first step in creating a repository. The "Repository name" field contains the text "hello-world" and is outlined in orange.](/assets/images/help/repository/create-repository-name.png)