Madan Lal Kosla then had to report to a job centre with his own passport in order to prove he was still alive.
"What if I had been away and someone else had opened that letter. They would think I'm dead. I had to pinch myself when I opened it," the 83-year-old told Manchester Evening News.
"My wife is very angry about this too. It has inconvenienced us both and caused us both a lot of stress," he said.
The letter read: "I am sorry to hear of your partner's death on the 18th of May. Please accept my condolences. I am sorry to write to you at this difficult time but as the claim for council tax support was in your partner's name I have cancelled payments from 18th of May."
Also Read
The council claimed the error occurred due to the UK's Department for Work and Pensions (DWP).
"The letter was generated as a result of direct information we were given by the Department for Work and Pensions (DWP) about Mr Kosla that we now know was incorrect. We receive hundreds of notifications each day from them and had no reason to suppose the information received about Mr Kosla was anything other than correct - hence our letter to his family."