Doctor Talitha Barrett said a change to a new model of geographic classification could mean medical practices receive about $400 less per full time practitioner per week, putting strain on their finances.

The Department of Health has confirmed the geographic eligibility criteria for three Medicare benefit items will move to a more recent classification system, including item 10991 which is an incentive for doctors to bulk bill.

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Under the new geographical eligibility system Bendigo would be a remoteness level two, equivalent to Melbourne's outer suburbs.

Doctor Barrett said she understood the incentive would be paid at a lower rate under the new level.

Item 10991 is classified as miscellaneous services. It is charged for people on health care cards, pension cards and those under 17.

Bendigo doctors can currently claim item 10991 at $9.50 per consultation, as the area is listed as a level three remoteness.

Dr Barrett said incentives to bulk bill patients could drop to $6 in greater Bendigo if the reforms are implemented as maps on the Department of Health website suggest.

Doctors cannot charge patients a co-payment if they bulk bill them. This means they could not recoup any loss to incentives.

Dr Barrett said item 10991 was charged on top of every other item number in an appointment for those eligible for bulk billing.

She said those who were bulk billed, such as the elderly, people with disabilities and children, were a large proportion of those seen in general practice.

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Dr Barrett feared the change would be "the straw that breaks the camel's back" financially for bulk billing doctors, after years of cuts to general practice.

She said if doctors could not bulk bill patients, many people would miss out on health care because they would not have enough money to pay fees.

"What they're proposing is a 40 per cent reduction in that [incentive], so that's a big impact in general practice," Dr Barrett said.

"General practice has already suffered in a freeze of the rebate, we haven't had a CPI [raise] in five years, and we've had a whole raft of other cuts.

"It's the opposite of what should be happening because we should be encouraging more care in primary care. In Bendigo we have one of the lowest socio-economic groups in the state, so the reduction is not warranted."

The Department has not confirmed which regions will be affected, saying details of changes are still to be finalised.

However its maps of the relevant models show Bendigo's classification as having changed. Maps also show a larger area surrounding Bendigo included in its classification than previously.

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A Department map of remoteness classification shows Bendigo is classified as level three remoteness under the current Rural, Remote and Metropolitan Areas classification dating from 1991.

The area around Bendigo stretches south from just below Ravenswood, north to above Whipstick, and east-west between Marong and Longlea under the 1991 classification. The rest of central Victoria is classified as remoteness level five.

Bendigo is classified as remoteness level two under the incoming Modified Monash Model. A greater area surrounding Bendigo falls under this classification, encompassing Goornong, Neilborough, Shelbourne, and Axedale.

The areas surrounding Castlemaine and Echuca are classified as a level four, while the rest of central Victoria is a level five.

The Department of Health said the changes will make sure metropolitan areas can no longer access incentives designed for rural and remote areas.

Changes will make sure that Australians living in these area have better access to bulk billing services, a spokesperson said.

These changes will take place on January 1.

Chief executive of Bendigo Primary Care Centre Glen Careedy said the changes would put more pressure on bulk billing, but the primary pressure was driven by changes in 2014.

These changes meant Medicare Benefits Schedule was still being paid at 2014 rates, he said.

The Bendigo Primary Care Centre used to bulk bill 75 per cent of clients, but is now trying to reduce that to 50 percent.

Mr Careedy said the changes could also make it difficult to recruit new doctors in Bendigo, as practices lost incentives connected to rurality.

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This meant it was less attractive for doctors to go to Bendigo when they could earn more somewhere more remote, he said.

"By changing the boundaries we are defunded from a rural classification, [Modified Monash Model level 2] is effectively a suburb of Melbourne," Mr Careedy said.

"We've got a huge demand in Bendigo at the moment, we've got a huge demand with the cold and flu season. We could put a doctor in here tomorrow and we would fill his books."

Dr Barrett said cuts to bulk billing incentives would cost more money in the long term, as patents turned to emergency departments for care.

"We know that if you get good GP care ... people are less likely to end up in hospital unnecessarily," Dr Barrett said.

"It's a backwards step. [It's] something the health system will regret in the longer term."

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