Since the first Draw Show in 1994, the National Lottery has made a life-changing difference to local communities and funded major projects such as The Angel of the North, Wembley Stadium and The British Museum.
More than 390,000 separate grants have been awarded to arts, charity, education, health, sports, heritage and environment projects.
Prime Minister David Cameron said: "National Lottery players raise £30 million a week making a real difference to their communities across the country.
"Our reforms to The National Lottery have ensured that their money once again benefits the original good causes boosting sport, arts, charity and heritage with other funding for projects that would not otherwise get off the ground.
"I would like to pay tribute to the founding father of The National Lottery, John Major. His vision has funded thousands of charities to look after our most vulnerable people, played a vital role in the success of Team GB and ParalympicsGB and helped build vibrant, internationally renowned heritage, arts and film industries.
"Happy Birthday to The National Lottery."
Sir John Major, who founded The National Lottery, said: "I am delighted to congratulate The National Lottery on its coming of age. Its birth was difficult, with many critics and few defenders. In the last eighteen years it has raised huge sums of money for good causes - both large and small - that have enhanced the lives of millions of people.
"Wherever you travel around the United Kingdom, Lottery-funded projects are evident, and those who play the Lottery each week can feel justifiably proud of their contribution towards improving the enjoyment, education, stimulation, good health - and overall life enhancement - of so many. Long may it prosper."
Culture Secretary Maria Miller said: "The incredible success of the London 2012 Games would simply not have been possible without the Lottery's £2 billion contribution. Happy Birthday to The National Lottery and we look forward to many more years of it making a difference to communities across the country."
The National Lottery has funded a range of projects:
• From helping Mo Farrah on his journey to double gold to a small child learning to swim.
• From investing in Oscar-winning films like The King's Speech to a theatre group for deaf children.
• Restoring much-loved national treasures such as The Cutty Sark and Hadrian's Wall.
• From over £60million for the Eden Project which regenerated a whole region to transforming thousands of public parks where we run, play and enjoy life.
Peter Wanless, Chair of the National Lottery Forum, said: "Most people know that Lottery funding has catapulted our athletes to extraordinary medal success, but it has also made an important difference to so many areas of British life. Every community has reaped the rewards of the popularity of The National Lottery over the past 18 years."
"National Lottery funding allows people to fulfil their potential whether that's in the arts, or sport, and preserves our rich heritage for generations to come. It gives a helping hand to people who need extra support including many of the most vulnerable in our society. Most Lottery-funded projects offer people the chance to volunteer - whether that is running sports clubs or dedicating a few hours a week to care for elderly people. National Lottery funding epitomises everything that is great about Britain."