Kevin Jones, 68, from Harlow, Essex, has encountered problems with NS&I following the death of his wife last month.
The 68-year-old told the BBC: “My wife died on 17 February. I contacted NS&I after completing a bereavement form online and getting no confirmation.
“I was told that, unlike all the other financial institutions I’d been in contact with, they didn’t acknowledge whether or not they had received the information.
“When I asked how long I should wait for the matter to be resolved, and get the money, as stated in her will, to me, I was told between six and nine months.”
He noted that four other banks, where his late wife had savings, dealt with the matter within weeks.
When Jones queried long delays, he says he was told the savings bank was “short staffed”.
“It’s tough enough when you’ve lost somebody but to have to deal with this…” he laments.