Freya and Graham McAnally had booked to have their nuptials at Manchester Town Hall in the north of England, and were stunned to find The Iron Lady crew shooting scenes in the building, which has similar architecture to the Houses of Parliament in London.
And the pair couldn't believe their eyes when they stepped out of the registry office to find Streep in her Thatcher finery smiling and applauding.
Freya says, "It was all very surreal - Meryl Streep was standing there dressed as Margaret Thatcher. It almost feels like it didn't happen.
"I thought it was amazing, the last thing you expect is an A-List celebrity at your wedding."
And the generous actress made sure the pair's nuptials got off to a great start by gifting them with signed photos, champagne, flowers, a glass vase and a copy of the film's call sheet for the day.
Graham adds, "They went above and beyond what they had to - it was lovely."