Auckland businessman Alex Swney might swap a swanky Ponsonby property for a jail cell today.

The 57-year-old former Heart of the City boss will be sentenced in Auckland District Court this morning after pleading guilty to charges laid by the Inland Revenue and Serious Fraud Office totaling fraud of more than $4 million.

The ex-mayoral candidate has been on bail since charges were laid last year but his lawyer Murray Gibson accepted at his last appearance there was no chance of a community-based sentence.

The most recent offences, which Swney admitted after a Serious Fraud Office investigation was executed, involved dishonestly using false invoices to obtain $2,527,005 from the organisation between February 2004 and October 2014.

In January, he pleaded guilty to four representative charges covering 12 years of offending and $1,757,147 of unpaid taxes.

Heart of the City - a city-centre business association registered by Swney in 1994 - has income-tax exemption on the basis that it was created to develop or increase amenities for the Auckland public.

But technically the defendant was a contractor of the organisation as the sole director of AGS Services Limited and the services he provided were taxable.

A summary of facts filed by the IRD showed how Swney issued "various fictitious invoices" to Heart of the City, from which he benefited.

Investigators questioned several organisations - including the New Zealand Herald - over the authenticity of the invoices and determined they were created "without authorisation".

Swney is also on the end of a civil action launched by Heart of the City, whose board announced the move in December after forensic accountants scoured their finances.

The case was first called behind closed doors in the High Court at Auckland in May.

The organisation told NZME. News Service it was committed to recovering "as much of the stolen money as is possible".

"Currently all detail surrounding the civil action is subject to court-ordered confidentiality so we're unable to discuss further."

Swney has declined numerous requests for comment.