Traditionally, when verifying a business listing on Google+ you would have to wait a few weeks for a post card that holds a verification code to be delivered to your business, and then you must enter it online.
Many users are unaware that you are able to instantly verify your Google Local Listing or Google My Business Listing using Webmaster Tools. Effective as of August 2014, your business is able to be instantly verified on Google My Business. Your business’s website must already be verified with Google Webmaster Tools in order to be instantly verified.
Make sure that you are signed in to Google My Business with the same email account you used to verify your website with on Webmaster Tools. If you have not done already verified your site, click here to learn how, or watch the video below.
You can get the instructions on how to verify with Webmaster Tools, or see other methods of verification here. Note that instant verification is only available for some business categories.