A Nationals MP has successfully lobbied the Turnbull Government for a third electoral office, despite an independent review into entitlements recommending against him receiving one.

The review - prompted by the $5000 helicopter charter enjoyed by former Speaker Bronwyn Bishop - recommended six electorates larger than 500,000 square kilometres receive a third staffed electorate office.

However as part of the mid-year financial update in December, the government made a decision that was more generous than the recommendation and handed a third office to a seventh electorate - Parkes in western New South Wales, held by Nationals MP Mark Coulton.

Mr Coulton said he didn’t believe the government going against the independent recommendation would undermine the credibility of the review process because the 500,000 square kilometre threshold was “arbitrary" and he understood the Labor Party and Independent MP Bob Katter had supported the change.

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“On either side of parliament I would be surprised if you found anybody who was resentful of me having this office, and certainly if you polled anyone in my electorate they would not think this was being too generous,” he said.

"I’m quite comfortable of the fact that I sought this and that the people of the Parkes electorate would recognise the unique nature of the population distribution and why this is possible.”

Mr Coulton said he made “quite a concerted effort" lobbying the government for a third office over a period of six months.

His electorate has recently expanded in size following a redistribution, but at 393,000 square kilometres it is still more than 100,000 square kilometres short of the 500,000 square kilometre threshold recommended by the independent review.

The Department of Finance's entitlements handbook states that electoral offices are to be used "for purposes related to Parliamentary, electorate or official business”.

The third office will be located in Broken Hill in far western New South Wales. Prior to the redistribution, the office was occupied by Liberal MP Sussan Ley. Alongside her main base in Albury, she has now moved into an office in Griffith previously occupied by Nationals MP Michael McCormack.

According to the mid-year financial update, establishing the seven extra offices will cost taxpayers $8.1 million over the next four years. The official entitlements handbook declares that electoral offices must have disability access, a "secure" reception counter, a kitchen and toilet and multiple office spaces.

Five of the seven seats are held by Coalition MPs.

“I know [the change is] bipartisan because Warren Snowdon is getting a third office, I’ve been talking to him - he’s Labor, he’s getting one at Katherine,” Mr Coulton said.

"I think Bob Katter, an Independent, is getting a third one.

"It’s not just one going to the Coalition - I think the Coalition has the other big seats from memory, but that’s just the nature of the job.”

Mr Coulton said the additional office would help him meet the needs of his constituents. According to his travel claims with the Department of Finance, he slept more than 150 nights in Australia but away from home in 2015/16.

The life of a rural MP

Nights spent away from home in 2015/16 by Parkes MP Mark Coulton

The decision to grant more electoral offices is the first major change of an imminent overhaul of politicians’ entitlements. The government has actually delayed the reforms despite a bill being drafted and ready for parliament.

The "Parliamentary Entitlements Legislation Amendment Bill" was marked for introduction in 2016 on a Department of Finance briefing document prepared in October obtained by SBS News under Freedom of Information law.

A spokesperson for the Finance Minister, Mathias Cormann, said the bill was not introduced in 2016 because of “the government’s very busy legislative agenda since the election” and noted the passage of the omnibus savings bill, income tax cuts, the establishment of the Registered Organisations Commission, superannuation reforms and "many other high priority pieces of legislation”.

The government spent the final days of Parliament attempting to amend backpacker tax laws it had previously introduced and securing passage of a weakened bill to reinstate the Australian Building and Construction Commission.