The communications watchdog issued the fine after DoorDash sent more than one million texts and emails between February and October last year in breach of the regulations.

An investigation by the Australian Communications and Media Authority found more than 566,000 promotional emails were sent to customers who had unsubscribed from the messages.

A further 515,000 texts had also been sent to prospective drivers for DoorDash without an option to unsubscribe.

The authority’s chair Nerida O’Loughlin said the investigation started after the watchdog received multiple complaints from customers.

“Australians find it incredibly frustrating when they receive marketing messages from businesses like DoorDash after they have taken the time to unsubscribe,” O’Loughlin said.

“It is unacceptable that DoorDash’s prospective contractors were sent messages without an unsubscribe facility about a business opportunity that they may not have wished to pursue.”

DoorDash will be required to appoint an independent consultant to oversee the company’s compliance with spam rules, as part of a three-year court-enforceable undertaking.

It will have to make regular reports to the watchdog.

The investigation revealed the food delivery company had mischaracterised its text messages to prospective contractors as being factual.

O’Loughlin said while factual texts are outside of the spam laws, the messages contained offers and incentives that promoted becoming a driver for DoorDash.

“When messages include this kind of content they are considered commercial under spam rules and must include an unsubscribe facility,” she said.

“DoorDash is a large business conducting high-volume marketing so there is no excuse for non- compliance. This is a further warning to all businesses that engage in email and SMS marketing that now is the time to review your spam compliance.”

-with AAP