Almost 800 Greene King pubs will be taking part in the annual festive anti-drink-drive campaign with Coca-Cola.
The pubco's brands Belhaven, Eating Inn and Hungry Horse have signed up for the 'Designated Driver' promotion, which runs until last orders on 1 January 2016.
Drink-driving falls
The reward for non-drinkers comes as the number of people driving after drinking continues to fall.
New research for the Greene King Leisure Spend Tracker shows that people who had consumed alcohol in the evening away from home, including a pub, restaurant or sports club, and were over the legal alcohol limit to drive, would be extremely unlikely to drive home.
The results of the survey highlighted 69% were more likely to get a taxi than drink and drive, 53% would get a lift, 49% would walk and 38% would take public transport.
Only 1% of respondents said they would actually drink and drive.
Attitude
Greene King's group marketing director Fiona Gunn said: "With drink-driving accidents being cut by half since 2004 and test failure rates falling every year, it is clear that voluntary initiatives such as the Coca-Cola Designated Driver campaign can have a positive impact on people's attitude to drink-driving.
"Much of the credit for the declines also lies with the Government and the police through their annual campaigns, which Greene King, as a responsible pub retailer, is more than happy to support."
A Coca-Cola Christmas truck keyring with two snap-off tokens entitles the designated driver to two free drinks of any combination from a 330ml glass bottle of Coca-Cola, Diet Coke, Coca-Cola Zero, 275ml Appletiser or Appletiser Apple & Pomegranate.
To get the keyring, the driver in a group of two or more diners simply has to show their car keys to their server.