New figures show 3,283 couples tying the knot opted for a Humanist Society service in 2017, compared with 3,166 who choose a Church of Scotland ceremony.
The statistics were published in a new report by Humanist Society Scotland, which concluded: "Previous census and Scottish Social Attitudes survey results have shown how beliefs have shifted over the last century.
"Once a country with a majority Christian population, Scotland is now a nation where most people see no evidence for a God, do not pray and do not identify with any religion."
The document also said the proporiton of Scots identifying as non-religious in 2017 stood at 59 per cent - rising to 69 per cent among those aged between 18 and 24.
The Beliefs in Scotland 2018 study of 1,000 adults also reported that Christianity is the biggest religion in Scotland, with 37 per cent identifying as Christian.
In response, a Church of Scotland spokesperson said: "This poll shows that more than one in three Scots identify with being Christian.
"That is actually an increase on the numbers in the Humanist Society Scotland's Survation poll of 2017.
"Whether we are many or we are few, the church will always seek to be a force for good in society."
Humanist Society Scotland also found 51 per cent of people in Scotland do not believe in life after death, while 34 per cent and 15 per cent are unsure.
It organisation's research also concluded that only 18 per cent believe in a judgement day where "god will punish some and reward others"
Fifty-three per cent of Scots answered that they never pray, while 13 per cent said they did talk to God everyday or almost everyday.
Meanwhile, 60 per cent reported that they never attend church other than for special occasions, such as weddings or funerals.
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