There is going to be a time in the very near future where AdWords are going to be able to set sitelink extensions at the account level. The announcement was made by Google about the release of account-level sitelinks in a tweet on August 30.
New account-level sitelinks save you time and help ensure your ads show with helpful links to your site. Learn more: https://t.co/RWLiUfjHyh
— Google AdWords (@adwords) August 30, 2016
The feature, at the point of this writing, is still rolling out, so it’s possible you wont’ be seeing it in your accounts yet. But, once its rolled out completely, you’ll be able to add or edit sitelinks at the account level from All campaigns. This information comes from the support page. When users add a new sitelink extension from the Ad extensions tab, they’ll be an option that will allow them to choose Account instead of just Campaign.
Although there are many cases for using both campaign and ad group-level extensions, there are a number of advertisers taht will find the ability to set them at the account level quite helpful. An example given by Ginny Marvin:
“Smaller sites that are already using the same sitelink extensions across all campaigns and advertisers that want to streamline offers and other messaging in sitelinks across an account will no longer have to remember to associate those extensions with every campaign.”