Sydney construction boss George Alex has been handed a maximum jail sentence of nine years and three months for conspiring to defraud the tax office of more than $10 million through a joint plan with four others.

The 53-year-old and his co-offenders — Lindsay Kirschberg, Pasquale Loccisano, Gordon McAndrew and Mark Bryers — faced a marathon six-month trial in the NSW Supreme Court over the scheme.

The jury was played 110 hours of secret recordings which laid bare a crude plan involving the non-remittance of PAYG tax over about two years.

But that material was merely a small proportion of the recordings gathered during a lengthy investigation.

Each participant was found guilty of conspiracy to cause loss and conspiring to deal in the proceeds of crime.

In sentencing, Justice Desmond Fagan on Friday said there was variation between each offender's likelihood of reoffending and prospects of rehabilitation.

But he was satisfied the plans were carried out largely for the benefit of Alex.

"The criminality and culpability of George Alex is greater than that of his co-conspirators," the judge said.

"The motive force for implementation of both conspiracies was George Alex's determination to maximise and accelerate extraction of money from the labour hire enterprise.

Justice Fagan said a fraud against the Australian Taxation Office (ATO) was "a fraud on all other taxpayers" who lawfully pay what is due for government services for the common good.

Alex will serve a minimum six years and two months, with his non-parole period due to expire in October 2030.

Loccisano and Bryers were each handed maximum sentences of eight-and-a-half years, with non-parole periods of six years.

Kirschberg and McAndrew also received identical sentences: a maximum eight years, with a non-parole period of five-and-a-half years.

He also commented that authorities could have stopped the fraud in January 2019, when business activity statements revealed a company had defaulted on remittance of $3.6 million of PAYG withheld from wages.

"The course of the investigation and trial may cause the Australian Taxation Office and the AFP (Australian Federal Police) to consider whether early disruption of discovered systemic non-compliance may be a preferable means of protecting the revenue," Justice Fagan said.

"Prompt ATO intervention" would have prevented $7 million in further revenue losses over the next 18 months, he said.

The lengthy trial itself must have also cost "many millions" in prosecution legal expenses, Justice Fagan added, while approximately $3.6 million in legal assistance has been provided to four of the offenders.

The five men appeared on video link from prisons and made friendly small talk with one another before the judge arrived.

Alex was taken into custody in September after Justice Fagan issued a bench warrant for his arrest when he failed to show up to court for the Crown's detention application.

Instead, he initially dialled in on a video link from rehabilitation at the Northern Beaches Hospital.

The court heard he was being treated for opioid addiction and receiving intensive physiotherapy for an emaciated leg, which was a result of a previous injury.

His lawyer unsuccessfully argued for Alex to remain in the rehab program because being taken into custody would reduce his access to physiotherapy.