A joint bank account has, traditionally, been a sign of commitment. As newlyweds start their lives together, it is perhaps the clearest way for them to say, to each other and to the world, “What’s mine is yours, and what’s yours is mine.”
Why More Young Married Couples Are Keeping Separate Bank Accounts

It doesn’t signal a lack of trust—to some, it’s a way for spouses to show they trust each other more.
Fuente: Caroline Kitchener - The Atlantic, 20 April 2018.
Fuente: Caroline Kitchener - The Atlantic, 20 April 2018.