KnowBe4 that we use for security awareness training also provides us with an addon for Gmail that lets you easily report phishing scams to them and to us.

Addons in the new Gmail interface by default are hidden on the left side of your browser window. To make them appear, click the arrow at the bottom right as shown in this screenshot:

The Phish Alert button is the red fishhook as shown in this screenshot:

To report a suspected phishing email, open the email (don't click any links or open any attachments included with a suspicious email), and click the Phish Alert hook. It will show you the subject and who the message is from. Be sure it is a message you want to report and then click the blue Phish Alert button as shown in the screenshot below:

If the email you are reporting is one of the test emails sent periodically by KnowBe4, Phish Alert will congratulate you for recognizing it as a suspicious email and reporting it to us as show below:

If the suspicious email is not from KnowBe4, it will alert them, alert the IT department, and delete the message from your mailbox as shown below: