The hot money is on the the new Princess of Cambridge being called Alice, as bookmakers revealed they have taken a six-figure hit because she is a girl.
Alice has long-running royal links - it was the name of the Duke of Edinburgh's mother and a daughter of Queen Victoria - and is the clear favourite with both Coral (5/4) and Ladbrokes (7/4), while Paddy Power has Charlotte as favourite at 5/2.
Bookies have estimated they face a payout of more than £500,000 after heavy backing for a princess rather than a prince.
Ladbrokes said its payouts included £15,000 to a man in Manchester having his first royal bet.
Spokeswoman Jessica Bridge said: "We're just as thrilled as royal fans that a healthy princess has been born despite it costing us plenty. Attention now turns to the name game and Alice, Elizabeth and Diana are the hot tips."
Coral's Nicola McGeady said: "Punters were spot-on with their gamble on the royal baby being a girl, leaving British bookmakers with a payout in excess of £500,000.
"Ten of thousands of bets are now coming in on Alice in the name betting, while Charlotte and Elizabeth have also been popular."
Charlotte, like Alice, has a long royal pedigree. It is the feminine of Charles, the name of her grandfather the Prince of Wales, and was the name of George III's queen, portrayed by Helen Mirren in the 1994 film The Madness Of King George.
Paddy Power spokesman Lewis Davey said: "Since the arrival of the new princess this morning, we've seen hundreds of thousands of pounds placed on the name of the young royal. Charlotte is still the 5/2 favourite, with Alice just behind at 7/2. We've also taken a number of big bets on Olivia at 50/1 which is our biggest mover of the day, now at 4/1."