Delivery workers from five major courier companies have given their employers an ultimatum – come up with a solution to a dispute over pay and conditions within a week, or they’ll walk off the job.

Union members at StarTrack, FedEx, Toll, Linfox and BevChain have voted to endorse a day of national strike action, after negotiations for new enterprise agreements at each company stretched past the five-month mark.

The Transport Workers’ Union has been pushing for commitments to limit the use of outside hire and to remove financial incentives to contract out work.

Contract workers are paid less, which the TWU says makes them more attractive to employers and creates job insecurity for permanent staff.

There have already been strikes in recent weeks at StarTrack and FedEx. But TWU Secretary Michael Kaine said “an industry-wide crisis requires an industry-wide response”.

Workers were exhausted and had approved more drastic action to push to have negotiations resolved before the Christmas boom.

“It is crunch time,” Mr Kaine said in a statement on Thursday.

“Christmas is fast approaching, and this has gone on long enough.

“Workers have acted responsibly throughout negotiations, it’s time for transport operators to bring a reasonable solution to the table.

“Several thousand workers have vowed to unite and take national action if that is what it takes to bring this attack on their jobs to an end as quickly as possible.”

The union argues its demands are the least the companies can do, after profiting off the back of record demand for deliveries amid the COVID-19 pandemic and lockdowns.

With stay-at-home orders afflicting NSW, Victoria and the ACT, Australians are shopping online more than ever. Australia Post says online orders in the three months to mid-September in NSW alone were up 58.8 per cent on the previous year.

It has already paused pick-ups from online retailers twice in recent months, to allow overwhelmed parcel services to catch up.

The pressure is only projected to worsen. In a report released by the Australian Retailers Association, CEO Paul Zahra said the elevated level of online shopping was expected to continue “right through Christmas”.

The TWU said Australia Post, which owns StarTrack, had reported record revenues of $8.27 billion last financial year, while FedEx turned over about $115 billion in the same period.

Similarly, Toll’s revenue was up $1.6 billion.

Australians are already facing longer than usual wait times for deliveries, with the sector bending over the pressure caused by the spike in online shopping, with much of the country enduring months of lockdown.

A spokesperson for StarTrack rejected union fears of job insecurity and said any further strike action would hurt customers.

“Any further industrial action will cause delays and delivery impacts, at a time when the delivery of essential items has never been more important,” they said.

“StarTrack continues to bargain in good faith, and we will continue to advocate for and support our people and our communities during this difficult and uncertain time.”

Its final offer to the TWU – a 9 per cent pay rise over three years – was the best among its competitors, they said.

FedEx, Toll, Linfox and BevChain have been contacted for comment.

-with AAP