Using the same method used by Office for National Statistics (ONS) – but adjusting for the significant number of UK couples who marry overseas – I estimate that the average (median) length of a marriage beginning today is 40 years before ending in either divorce or death.
This contrasts sharply with the oft-quoted figure of 12 years, which is the average (median) length of marriages that end in divorce.
Previous analysis by ONS estimated that the average marriage beginning in 2010 would last 30 years. So why the big improvement?
Part of the reason is an adjustment for overseas weddings. Since 1990, some 30-60,000 people per year have married overseas. Assuming most of these are couples, a conservative adjustment of half this number boosts the total number of ‘England & Wales weddings’ by 6% to 17% per year. This produces a slightly lower, but more realistic, estimate of divorce rates.
The biggest reason is falling divorce rates. Back in 2010, ONS projected that 21% of couples would divorce within 10 years, for example. Adjusting for overseas weddings would reduce that by 2%. But with eight years data on these couples, actual divorce rates are 4% lower still. So the final divorce rate figure for 2010 couples over their first decade of marriage is likely to be 15%.
With couples doing so much better early on, lifetime projections for divorce have also fallen as a result. The original ONS projection for 2010 couples was 42%. Adding in overseas weddings reduces this to 39%. My latest estimate for 2010 couples is now 34%.
So for couples marrying in 2010, the projected length of time at which half of all marriages have ended through either divorce or death has thus increased from an original projection of 30 years to 35 years, or from 33 years to 38 years if I adjust for overseas weddings.
For couples marrying in 2017, the average length of marriage is now 38 years if I don’t take overseas weddings into account and 40 years if I do, which I should.