Legal and General found financial pressures held up 19% of divorces, particularly since 2020.
The financial services provider found the income of nearly half of those who split fell by an average of £9,700 in the year after separation.
Just one in five couples discuss their pensions when dividing assets, focusing instead on things like the home.
Paula Llewellyn, of Legal & General Retail, said: “Many couples have not even sorted paperwork to ensure a clean break from their financial obligation to one another.
“By consulting a financial adviser, people increase the likelihood of a divorce being fair and equal.”
The Pensions and Lifetime Savings Association (PSLA) is today releasing guidance on how work pension scheme providers could help those splitting up.