An elderly man who thought he had lost an envelope containing his life savings is delighted the $23,000 has been found by police officers at his Greymouth home.

The 90-year-old withdrew the money from his bank on Friday - it was given to him $100 bills in a white envelope - and then went to a cafe for a cup of tea, but his movements were unclear from there.

Police had earlier appealed to the public to help find the man's cash which was his life savings.

It was thought he may have left the money somewhere in Greymouth.

Two police officers spent days going through his house trying to find the money, police spokeswoman Barbara Dunn told NZ Newswire on Thursday.

"His house is immaculate, but it was very well hidden."

She could not say exactly where the money was found, but it has since been deposited into the man's bank account.

Ms Dunn says police have received a large number of calls from concerned members of the public, including calls from the United States and Canada.

"I had a guy ring up and say I'll just write out a cheque and send it now, but I said: `hold on, we're hoping to find it'."

And thankfully they did.

"Delighted to have the money back and from what the guys have been saying he's actually very alert and with it but obviously having a bit of an issue with his short term memory for those sort of details," Ms Dunn said.