In addition to that, a number of people reported issues with their Telstra mobile phones.

Those affected were hoping the issue would be fixed by Wednesday, with most customers choosing to use cards instead of cash in 2019.

Northpoint Lotto and Gifts co-owner Jack Murnane was taking it in his stride, but said it would have been no laughing matter if the outage had occurred last Thursday.

"We're lucky because it's been a quiet day," Mr Murnane said.

"If it had happened last Thursday with the $150 million Powerball draw, we would have been in trouble."

The Clocktower Cafe in Lava Street was also without eftpos.

Owner Frank Corona thanked his customers for their patience.

"We're lucky because we've got a bank next door because about 75 per cent of our customers use cards now," Mr Corona said.

Totally Workwear owner Catherine Simpson said the store had been without eftpos the whole day.

She said it was an issue as many customers used cards to pay for their purchases.

"Customers very rarely have cash these days," Ms Simpson said.

"We've had customers having to go to the BP and get cash but some haven't had time because they have been on their way to work.

"We had one guy who came in to get a pair of boots on his way to work but he had to put his old boots back on because he didn't have cash."

Ms Simpson said staff members had advised customers they would stay open later than 6pm to give customers the chance to pop back in with cash.

"We're happy to stay open a little later than usual," she said.

Macey's Bistro was also dealing with the issue of having no eftpos, with staff forced to provide cash out for their customers at lunch.

The city's major health provider, South West Healthcare's Warrnambool Base Hospital, was not severely affected.

A South West Healthcare spokeswoman said Telstra was not South West Healthcare's service provider.

"However, many of the mobile phones personally owned by our on-call doctors are Telstra supported," she said.

"Alternative arrangements have been made and there's no impact on our services."

Warrnambool Country Meats owner David Wiese, who went cashless in August, was thanking his lucky stars he had a mobile eftpos machine, which was not affected.

"I've never had an outage," he said.

A Telstra spokesman said the issue was being investigated.

"We're aware there is an issue impacting some 3G services at one mobile base station in the Warrnambool North area," he said.

"We're working as quickly as we can to restore services."

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