The FTSE 100 betting giant, previously GVC Holdings, said in the six months to July total net gaming revenues were up 11%. Online net gaming revenues were up 22% in the second quarter "driven by sports betting" - taking Entain to 22 consecutive quarters of double-digit online growth.
Entain, which is also behind betting brands including Coral and Sportingbet, said the Euros are shaping up to be its biggest ever sports betting event, with more bets placed than for the 2018 World Cup. Today England is the most-backed team by people in the country, with France having been Britons' initial pick to win, the company said.
Revenues across its retail sites have been hit hard by lockdowns, falling 40% to £875 million in the year to end December, but the company said it is seeing "encouraging early trends in retail as restrictions eased in phases" between April and June.
Bosses said they expect full year underlying cash profits of £850 million - £900 million, ahead of consensus.
Boss Jette Nygaard-Andersen -the first female chief executive of a major listed betting company - said: "We are upgrading our expectations for the full year and we remain confident and excited by the breadth and scale of the long-term sustainable growth opportunities ahead of us."
The firm is seeing continued US growth and has made acquisitions in Europe in recent months, including snapping up Swedish online bookmaker Enlabs.
Entain also said on Thursday that it plans to double its in-house studio workforce to 300 across its three studios in the UK, Italy and India - with eight roles being created at the UK site in Oldham - as Nygaard-Andersen pursues a Netflix-style focus on original content. The group is creating new games and immersive experiences to lure online customers, with its first VR product - a multi-activity sports club - due later this year.
Entain is currently the third-largest operator in US online gambling space behind Paddy Power owner Flutter and US firm Draft Kings, offering BetMGM -a joint venture with Nevada-based casino operator MGM Resorts.
In January the firm rejected an approach from MGM that valued the business at £8.1 billion, saying that it "significantly undervalues the company and its prospects”. MGM would be permitted to return with a higher bid later this month.
Analysts at Peel Hunt said "it appears to have come home already" for Entain.
Shares rose by nearly 2%, or 33p, to 1841p, in early trading on Thursday on the update.