The credit card brand’s campaign, created by Ogilvy, will use its illustrative style to promote the role of small businesses as heroes of the high street, ahead of Small Business Saturday on 7 December.
As part of the activity, people with American Express cards who spend more than £10 on them with participating small businesses on the day, will get £5 credit.
The campaign kicks off today and will include a 30-second TV spot, out-of-home six-sheets across the London Underground, rail stations and streets, supported by digital, search and regional radio ads.
The voiceover for the TV ad asks people to "support the heroes of our high street"; suggesting shoppers "think big" and "shop small".
The creative director behind the campaign was Arthur Parshotam. Kuntzel & Deygas directed the TV spot through Add a Dog.
American Express channels on Facebook, Twitter and YouTube will support the initiative, as will a below-the-line campaign targeting card members and small businesses.
Melissa Weber, the director, UK brand communications, American Express, said: "We’re excited that Small Business Saturday has made it to British shores and are delighted to be part of an initiative that celebrates the contribution small businesses make to our economy and local communities."