A local citation is any listing of your business's name, address, and phone number (NAP) on a directory or listings site. Citation building is the work of submitting that information to directories, keeping it consistent across listings, checking for duplicates, and verifying each profile. For a service business — plumbing, HVAC, roofing, electrical — citations are one of the inputs Google says it uses to judge prominence, alongside links and articles. They are not a shortcut to rankings, and Google publishes no citation count that a business is required to hit.