The couple want to dispel rumours their marriage is on the rocks by holding a private ceremony at their Wiltshire home for close family and friends.
'They've worked hard to iron out their differences to get through the tough times,' an insider tells the News Of The World.
'It's going to be a very emotional day and that's why they want the people who are closest to them to share it with them. They know a strong marriage takes constant effort.'
Madonna's daughter Lourdes, 11, will do a special reading at the intimate gathering and Stella McCartney is expected to design the 'wedding' outfit.
Madonna, 49 - who married Guy, 39, in December 2000 - is also mum to son Rocco, 7, and adopted Malawi-born David Banda, 2.
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