DUBLIN, Aug 13 (Reuters) - Flutter raised its

full-year guidance after a much better than expected second

quarter and said it has no plans "at this stage" to follow rival

Draftkings ( DKNG ) in adding a surcharge to customer's

winnings in high-tax U.S. states.

Flutter, the world's largest online betting company, expects

to boost its previous forecast for a jump of around 30% in

full-year core profit thanks to a 17% rise in second-quarter

profit, bookmaker-friendly sports results and third-quarter

momentum.

It expects core profit of $680 million to $800 million in

its U.S. Fanduel brand versus the $635 million to $785 million

seen in March and last year's $167 million, which was its first

full year of profitability in the rapidly growing market.

Core profit of $1.69 billion to $1.85 billion is now seen

its others markets, which include the Paddy Power and Betfair

brands in Britain and Sportsbet in Australia. That compares to

the $1.63 billion to $1.83 billion forecast previously.