Martin Lewis has urged couples to have a serious conversation over finances in case tragedy strikes.
The Money Saving Expert said not all couples know the exact details of household finances, with it usually just being one party taking charge of everything.
And the problem often emerges when it comes to what Martin called the 3Ds – death, divorce and dementia.
Speaking in ITV's Martin Lewis Money Show, he brings up an example to show how lack of communication could leave the other partner vulnerable.
He says: "It's generally women who came up to me and said 'I've lost my husband, I do not know how to deal with the finances'.
"In one case, a woman, whose husband died two months before, she couldn't pay the mortgage because she didn't know where the savings were."
He suggests the one who is looking after the finances makes a "financial fact sheet" listing all the relevant products and share it with the partner.
Martin adds: "You talk to your partner, you say to them 'this is what will happen'.
"Make sure they at least understand it in case they're not managing it."
The financial expert previously revealed that you have until Monday (November 9) to use the Current Account Switching Service to get a £100 bonus before Christmas Day.
New customers who switch their banking to HSBC and Lloyds in the next few weeks will get £125.
He also said thousands of retired British women, or women over 80 years old, could be owed up to £82,000 and that they should check their pension.