London Mayor Sadiq Khan joined UK television icon and writer Fry, 67, and former England football manager Gareth Southgate in being knighted in the latest list.
Fry, best known for playing his idol Oscar Wilde in the 1997 movie "Wilde" and hit British television comedy "Blackadder" was recognised for services to mental health awareness, the environment and to charity.
Fry, who has a form of bipolar disorder, has spoken openly about his struggles with manic depression.
He told the PA news agency that he felt "startled and enchanted" after receiving the letter informing him of his knighthood.
"When you are recognised it does make you feel a bit 'crikey', but I think the most emotional thing is that when I think of my childhood, and my dreadful unhappiness and misery and stupidity, and everything that led to so many failures as a child," Fry added.
Khan, one Britain's most high-profile Asian-origin politicians, was honoured for political and public service.
The 54-year-old has led the UK capital since 2016 and earlier this year became the first London mayor to win a third term.
Four victims of the Horizon IT scandal, in which hundreds of sub-postmasters were wrongly convicted of fraud, theft and false accounting because of faulty software, were also honoured.
Lee Castleton, Jo Hamilton, Christopher Head and Seema Misra were recognised with an Order of the British Empire (OBE) for their work campaigning for justice.
The previous Conservative government unveiled legislation in March to exonerate those wrongly prosecuted and compensate them after a TV drama renewed focus on their plight.
More than 1,200 people received honours in the latest list, which is decided by an honours committee.
The king or other leading members of the royal family hand out the awards at ceremonies during the year.
"Each and every day, ordinary people go out and do extraordinary things for their communities," said Prime Minister Keir Starmer.
"The New Year Honours List celebrates more of these unsung heroes, and I thank them for their incredible contribution," he added.
Mulligan received an award as a Commander of the British Empire (CBE) while Nobel Prize-winning novelist Kazuo Ishiguro was made a Companion of Honour for services to literature.
Southgate was knighted for services to football after leading England to the finals of the past two European Championships, as well as to the 2018 World Cup semi-final.
His eight-year reign ended without a major trophy after England's 2-1 defeat to Spain in July's European final.
Also honoured were several British athletes who competed in the Paris Olympics this summer, including 800-metre gold medallist Keely Hodgkinson and two-time Olympic mountain bike champion Tom Pidcock.
The king also personally honoured two of his medical staff after he was diagnosed with cancer in February. His GP Douglas Glass, who was also attending Queen Elizabeth II at her death in Balmoral in September 2022, and his consultant physician Richard Leach were both awarded with levels of the Royal Victorian Order.
