Global postal services expect to sort through that number of wish lists by the time Christmas rolls around, according to a survey by the Universal Postal Union (UPU), which coordinates the world's mail systems.
That is two million more than the haul estimated in a similar survey in 2007.
Postal services in Canada, France, Spain and Ireland "are reporting increases in the number of letters sent to Santa, Père Noël or the Three Wise Men, from last year", UPU said in a statement, referring to the French and Spanish versions of the famous gift-deliverer.
Last year the French held the record with 1.7 million letters, followed by Canadians, who penned 1.35 million.
Frequently addressed just to "Santa, North Pole", these letters are handled by some 20 postal services worldwide.
Many have created formal programmes to help answer the missives, UPU said.
The US postal service even encourages people to "adopt" Santa letters, sending gifts under his name back to the authors, according to its website.
As a "universal superstar", Santa maintains addresses in many parts of the world, UPU said.
One of the more popular is Finland's Santa Claus Village, on the Arctic Circle, which last year received more than 500,000 letters from 192 countries, according to the Finnish postal service.
Post offices in locations with names reminiscent of the holiday season, like Christmas Island in Canada, also receive large amounts of mail this time of year, UPU said.
Established in 1874, the union is the second oldest international organization in the world.
With its 192 member countries, the Swiss-based group calls itself "the primary forum for cooperation between postal sector players".