This holiday season you can show your appreciation to your Amazon driver and spread holiday cheer.

Starting this week in the U.S., customers who say, “Alexa, thank my driver” will trigger a tip toward the last worker who delivered a package to that customer. The $5 comes at no cost to the customer, and Amazon said in a blog post that it will run the promotion for the first 1 million thank-you’s received.

The five drivers who receive the most customer thank-you’s will also be rewarded with $10,000 and an additional $10,000 to their charity of choice, Amazon said.

You’ll need an Alexa-enabled device such as Echo or Echo Show if you want Amazon to pick up the tab. Otherwise, you can open your front door and slap $5 directly into the hand of that delivery person yourself.

The timing of the promotion comes as Amazon is facing a lawsuit in Washington, D.C., where Attorney General Karl Racine’s office filed a consumer protection lawsuit against the e-commerce giant, alleging that the company stole tips from drivers and deceived consumers about a tipping model in its Amazon Flex service.