Under the changes, set to begin on April 15, the frequency of letter deliveries will be halved, with posties instead focusing their efforts on the more lucrative parcel delivery business.

Households now received two letters per week, and that is expected to fall to just one in the next five years

But the parcel delivery service is performing well, with a record of almost 100 million packaged delivered over summer.

Under the changes that start on Monday, priority mail, express letters and parcels will be delivered every day, while standard letters and unaddressed mail will be dropped off every second day.

The overhaul is permitted under new performance standards for the postal service, implemented by the federal government, which has committed to modernise operations.

In the first half of the 2023-24 financial year, Australia Post reported a half-year profit of $33.6m, as the letter section reported a loss of $182m in that period.

Australia Post chief executive Paul Graham welcomed the start of the delivery overhaul, remarking that it was a “significant day in the modernisation of Australia Post”.

“The new regulations will enable Australia Post to focus on what Australians want most, flexible and more reliable parcel deliveries with enhanced tracking technology and more delivery options,” Mr Graham said.

The Australia Post boss said the billions spent on online shopping required the service to instead focus on ensuring reliable parcel deliveries.

“With the strong support of the federal government, this is an important first step for Australia Post to address those financial losses by focusing its services on the growing parcel-delivery business and a better experience for our customers,” Mr Graham said.

The change will be implemented progressively across Australia through to the end of 2025.