A shortage of cucumber, lamb and turkey has hit Subway stores from Kaitaia to Invercargill.
A sign at Auckland's Queen St store said: "Due to the critical supply issue with cucumber we need to reduce the amount of cucumber on sandwiches for a limited time."
At Subway Eden Quarter in Mt Eden, a notice said: "We are currently out of stock of our turkey and roast lamb products due to unforseen circumstances until further notice."
Subway marketing manager David Herrick said there was a seasonal shortage of cucumbers because of cold growing conditions, which led Subway to look at sourcing them from Australia.
"But what's happened in Australia is that all the growing fields there were hit by serious flooding a couple of months ago. Therefore they can't supply us," said Mr Herrick.
Subway management has told stores nationwide to use less cucumber until supplies are restored.
Six-inch subs will now get two slices of cucumber instead of three, and foot-longs will get four instead of six.
Subway Britomart acting store manager Uma Nam said: "We order cucumbers from one place and we are not getting stock from them."
Mr Herrick added: "We expect it to be resolved next week."
Sally Shen, duty manager of Subway Eden Quarter, said although she had a small amount of cucumber, there was no turkey or lamb in stock.
Subway management did not return the Herald's calls regarding the "unforseen circumstances".