Hastings Countdown customers had to resort to paying cash for their groceries on Wednesday as a "technical error" caused the Eftpos terminals to fail for nearly two hours.
Countdown Hastings store manager Richard O'Mahony said they were unable to provide any sales figures and said the checkout systems were down from 3.15pm until about 5pm - a peak time for many shoppers.
"This didn't affect any other parts of the store and we're sorry for any inconvenience caused to our customers. Everything's back up and running as usual for us now," he said.