Almost half (46%) of women over 40 who live with a partner do not have a pension according to research by Prudential.
Additionally, British couples are reluctant to speak about the finances that will support them in later life. One in five couples (20%) have never discussed joint retirement planning.
Vince Smith-Hughes, head of business development at Prudential cautioned: "Women who think they can rely on their other half's pension income without having discussed retirement plans with their partner - and preferably with a financial adviser too - could find themselves in financial trouble, especially if they outlive their loved one."
With current retirees, only half made a joint decision about their annuity.
Prudential also found over half (56%) have not calculated how much money they will need in retirement, with a further 40% of respondents revealing they have no retirement plans in place.
Smith-Hughes said: "Pensions may not seem like the most exciting topic for a couple in their forties to be discussing, but couples who have not put time aside to discuss their retirement income plans run the risk of spending their later lives worse off than they had expected.
People may feel they can't afford to significantly boost their retirement savings in the current financial climate, but taking even the smallest of steps can have a positive impact. Joining a workplace pension scheme, considering a joint life annuity, so the income will continue after one partner dies, and topping up National Insurance contributions, are all options which can increase income in retirement. These crucial issues should be discussed between couples and, in turn, with their financial advisers."
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