The fall in the number of couples tying the knot "shouldn't be a surprise", says the Marriage Foundation's Harry Benson.
Latest figures from the Office for National Statistics show a 6.5% drop in opposite-sex weddings in England and Wales between 2018 and 2019, falling to 213,122 - the lowest on record since 1862.
Religious ceremonies also reached a record low, falling by 21% in the same period to 213,122 in 2019 - or 18.7% of the population.
The number of marriages that took place in England and Wales were analysed by age, sex, previous marital status and civil or religious ceremony.
The average age for opposite-sex couples getting married in 2019 was 34.3 years for men and 32.3 years for women.
Dr James Tucker, Head of Health and Life Events Analysis at the ONS said, "The number of opposite-sex marriages has fallen by 50% since 1972.
"This decline is a likely consequence of increasing numbers of men and women delaying marriage, or couples choosing to live together rather than marry, either as a precursor to marriage or as an alternative.
"Future analysis will show the impact of the pandemic on marriages rates."
Commenting on the figures, Mr Benson said that current policies were not helping.
"It shouldn't be a surprise that marriage rates are falling. Hostile policy makers pretend marriage doesn't matter," he said.
"While public policy massively penalises low-income couples who marry. Despite this, most young adults still want to marry and the evidence says that this is a good choice."
In a recent Marriage Foundation survey of unmarried UK adults aged 18 to 30, nearly nine in 10 believed they would be more likely to get married. Nearly a third (29%) said they would tie the knot if weddings were cheaper.
Another recent study by the organisation found that married poor couples experience greater stability than unmarried rich.
The study looked at data from 2009 to 2018 and found that cohabiting parents were 3.4 times more likely to split up compared to married parents (6.5% versus 1.9%). This gap was reflected across income brackets.
"Even after taking into account mothers age, education, ethnicity, household income and relationship happiness, the odds of cohabiting parents splitting up are consistently twice as high as those of married parents," said Mr Benson.
"We also know from research that married families coped remarkably well during lockdown while unmarried cohabiting parents tended to fare worst.
"The simple message is that marriage works and why we fully support the Law Commission's proposals to liberalise wedding rules might help lower costs.
"But when almost all government ministers think marriage is important in their private life, why do we have the most anti-marriage public policy in Europe?"