The funeral of Baroness Thatcher will take place on Wednesday, 17 April, Downing Street has announced.
A big funeral ceremony will take place at London's St Paul's Cathedral, with her coffin being carried through the streets of London on a special carriage.
The Queen and her husband the Duke of Edinburgh will be at the service.
Lady Thatcher will not have a state funeral but will have the same status as Princess Diana and the Queen Mother.
A ceremonial funeral is slightly less than a state funeral which is normally reserved for kings and queens. The Queen herself must give permission for a ceremonial funeral.
MPs will return to Parliament after its Easter recess this Wednesday, to pay their tributes.
Prime Minister David Cameron described Lady Thatcher as a "great Briton" and international leaders, including US President Barack Obama and German Chancellor Angela Merkel have praised her.
But small gatherings happened on Monday night in various parts of the UK, like Glasgow, Bristol and London, with people taking part saying they were celebrating her death.