A fiercely contested bidding process has been under way between four parties to hold the licence, which Camelot has operated since 1994.
But officials said Allwyn is now the preferred applicant to take over the venture in 2024.
The Gambling Commission said: “The selection of Allwyn as preferred applicant follows a fair, open and robust competition which received four applications at the final stage.
“This is the highest number of applications since the first National Lottery licence was awarded in 1994.
“Allwyn has committed to investment in the National Lottery that is expected to deliver growth and innovation across the National Lottery’s products and channels, resulting in increased contributions to good causes, subject to the protection of participants and propriety.
“The Gambling Commission is content that all applicants are fit and proper to operate the National Lottery.
“Recognising our role as a responsible regulator we are also satisfied that no application is impacted by sanctions related to the conflict in Ukraine.”
The other applicants were Sisal Spa, Camelot and The New Lottery Company Ltd. Camelot has been named “reserve applicant”.
Gambling Commission chief executive Andrew Rhodes said: “In its lifetime, the National Lottery has raised more than £45 billion for good causes and is rightly seen as a great national asset.
“Our priority was to run a competition that would attract a strong field of candidates. Having received the most applications since 1994, it is clear that we’ve achieved just that.
“I am confident that the success of the competition will lead to a highly successful fourth licence – one that maximises returns to good causes, promotes innovation, delivers against our statutory duties, and which ultimately protects the unique status of the National Lottery.
“We look forward to working with all parties to ensure a smooth handover.”
Allwyn said: “We welcome today’s statement by the Gambling Commission that we have been selected as the preferred applicant for the fourth National Lottery licence.
“Our proposal was judged to be the best way of growing returns to good causes by revitalising the National Lottery in a safe and sustainable way.
“The appointment of Allwyn will breathe fresh life into the National Lottery.”
Camelot chief executive Nigel Railton said: “I’m incredibly disappointed by today’s announcement, but we still have a critical job to do – as our current licence runs until February 2024.
“We’re now carefully reviewing the Gambling Commission’s evaluation before deciding on our next steps.”