Starting in April, Google will require ad display URLs and destination URLs to match. This policy will include redirects and vanity URLs. Google is making this changed based on feedback from both users and advertisers.
This would seem problematic to clients using agencies like ChannelAdvisor to run their paid search accounts, since most agencies use a redirect URL for tracking purposes. DON’T worry, as long as the agency redirect resolves to a landing page that matches the ad’s display URL, you won’t be penalized.
For example, if the display URL in your ad is www.yoursitecom and the tracking redirect on your destination URL looks like http://tracking.searchmarketing.com/click.asp?aid=12345678999 but resolves for the user to www.yoursite.com (or a sub-domain), your ads will meet the new Google requirement.
Sub-domains will continue to be accepted, as long as the top-level domain matches the URL of your landing page.
written by Erin Gordon — erin.gordon at channeladvisor.com