The mailer, which contained a pack of fuzzy felt shapes to play with and asked recipients "Does your bank give you that warm fuzzy feeling?", was described by the judges as "strong and insightful, reflecting the brand".
It generated a response rate of 6.3%, more than twice that of the control pack, which achieved a 2.6% response.
One judge said: "The industry gets criticised for sending out junk mail and over-egged pieces. With First Direct's piece, you get it, hold onto it and reach out to it --a testament to fine work that is right for its target audience."
The campaign also won gold in the financial services category, helping Craik Jones tie with Story as the agency with the most gold awards.
Craik Jones' three other golds were for: Media - Business Direct Mail (high volume) for Virgin Trains; Creativity - Creative Solutions for Refuge; and Strategy - Customer Loyalty for Diageo's whisky brand Bell's.
Story's four golds were in: Markets - FMCG for The Glenmorangie Company; Media - Online Advertising for The Glenmorangie Company; Media - Consumer Direct Mail (low volume) for First Direct; and Strategy - Launches for The Glenmorangie Company.
Kitcatt Nohr Alexander Shaw was the next most awarded agency with three golds for: Markets - IT/Telecommunications for Logitech; Media - Inserts for NSPCC; and Creativity - Copy for The Samaritans.
Among the remaining strategy categories, the Customer Acquisition gold went to Partners Andrews Aldridge for Visit Wales and the Brand Building gold went to Draft FCB London for Oxfam.
In the new category of Media - Digital Direct 北京赛车pk10, the gold went to 20:20 London for Sony PlayStation2's '24: The Game'.
Other media wins worthy of mention was the Broadcast gold for the pairing of Watson Phillips Norman and Mike Colling & Company for Which? and the Multiple Media gold for Partners Andrews Aldridge for Haringtons Hairdressers.
Media - Email was won by Dare for The AA, with judges commenting the standard of entries was getting higher every year.
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