Official figures show 27,547 marriages were registered last year, nearly 3000 down on the previous year and reversing a trend after three consecutive increases.
There were only 23 more marriages than in 2009 and around 2000 more than the figure for 1890, according to the National Records of Scotland (NRS).
The data, which is produced each year, also showed falls in both the number of births and deaths in 2013.
Dumfries and Galloway remained the council area with the greatest number of marriages - more than 4000 - largely thanks to the 'wedding capital' of Gretna Green.
There were 2717 marriages in Edinburgh, the area with the second highest number, while 2584 took place in Glasgow.
Dumfries and Galloway also saw the highest number of civil partnerships performed within its borders, with 14 male couples and 55 female couples tying the knot there last year. Overall, there were 530 civil partnerships, down 44 on the previous year. Shetland was the only council area where no such ceremonies took place.
Tim Maguire, spokesman for the Humanist Society in Scotland, said that the drop in the number of marriages had been noticed by the wedding industry.
He said "The number of ceremonies we performed last year was up by about 4% on the year before, but the year before that they had gone up by more than one-quarter, so the pace has slowed.
"I'd say the drop in marriages is down to the fact that there was a 13 in the year. People may be drifting away from religion, but they still appear to be superstitious."
The number of births decreased from 58,027 to 56,014, while deaths dropped from 54,937 to 54,700, which is the fourth lowest number recorded in more than 150 years.
Tim Ellis, chief executive of the National Records of Scotland, said the number of births fell in 2013, continuing the trend of gradual decline from the most recent peak of 60,041 in 2008."
He added: "Levels of births and deaths are both relatively low in historical terms and there have been more births than deaths each year since 2006."
Recently annual deaths have been below 55,000, compared to around 60,000 to 65,000 from the mid-1940s to the mid-1990s and larger numbers before then.