Six months after opening debate on changing South Australia's time zone to align with the eastern states, or winding back 30 minutes to be closer to Western Australia, the State Government says it favours the east.

This is despite most business community respondents believing there was "little to no inconvenience" under the current arrangements, and only 14 per cent believing there was a significant advantage in moving forward to Eastern Standard Time (EST).

SA, like the Northern Territory, operates in Australian Central Standard Time (ACST), half an hour behind the eastern states and 90 minutes ahead Western Australia.

In February, the Government suggested a time zone shift could make the state more business friendly, a proposal that has been brought up several times before and led to a broad-based survey back in 2008.

The Government said two more recent reports compiled from community consultation had found there would be "significant advantages" by aligning with the eastern states, including a business "boost" through better communication with suppliers.

It said it would eliminate problems with computer systems, aid tourists unable to understand changing time zones, remove broadcast delays in news and entertainment, increase outdoor activity by offering 30 minutes extra sunlight at the end of the day, and remove a perception that SA was "out of touch" with the eastern states.

A final report compiled by the SA Centre for Economic Studies and completed in May, however, focussed on the cost-benefit analysis of a potential shift, and found the results "uncertain".

The report found that there was a range of potential benefits and costs of shifting forward to either EST or backwards half an hour to "true" Central Standard Time (CST), with many outcomes contradicting each other.

Some 10 per cent of responding businesses said there would be a significant disadvantage of a shift to EST, and were worried about the "costs and risks" of a greater share of operations taking place before dawn, or increased time difference from Asia.

Sorry, this video has expired Will SA change its time zone? Debate rolls on

This is despite those businesses who thought there would be an advantage highlighting increased foreign direct investment, business revenue, reduced business costs, a reduction in construction accidents and easier collaboration with eastern state colleagues, clients and suppliers.

This was offset by costs to businesses, however, which included a reduction in trade with eastern states, decreased exports to Asia-Pacific Economic Cooperation (APEC) nations, decreased sales to Western Australia, increased accident rates in construction, and software costs to implement the new time zone.

Wider community costs included increased energy usage, less time in the evenings with family members (in farming families), children commuting to school before dawn, and road crashes.

This is despite the benefits of a reduction in energy usage, a "reduction in crime", and improved health from longer sunshine in the evening.

'Not surprised' by small number of businesses backing change

Business SA chief executive officer Nigel McBride said it "didn't surprise" him that only 14 per cent of responding businesses saw a major advantage.

Premier Jay Weatherill said in February that a time zone shift in SA would only proceed if it were deemed positive for business. ( ABC News: Nick Harmsen )

He said SA only accounted for about 4 per cent of Australia's exports, despite having more than 7 per cent of the population.

"People don't understand the international perception of time zones ... we're not a very international facing economy," Mr McBride said.

"The east coast is one of the great economic zones we want to be trading with and trading in.

"We want to say that if you're a national or international country and you set up in SA, you bring investment here, you're part of the main game of the economy of SA, which is in the south-east time zone."

Premier Jay Weatherill pointed out that SA's population was about 1.7 million people in a country of 22 million.

"Seventy-five per cent of the nation's economic activity is on the eastern seaboard," he said.

"We want to look outwards and beyond our own borders for our future prosperity. That means being better connected to the nation."

A shift to EST was estimated to produce net benefits of $2.5 billion, while a shift backwards to true CST was estimated to produce a benefit of $0.3 billion.

"Each shift in time zone is estimated to produce net benefits over its costs, however, the shift to EST produces a substantially larger benefit," the report said.

"The analysis is highly sensitive to the estimates of the benefits arising from increased trade as a result of matching a time zone more closely with a trading partner, whether interstate or overseas.

"The uncertainties regarding the impact on business suggest that, should either change in time zone be considered for adoption, the Government engage in extensive consultations with SA businesses that have extensive trade with the eastern states and Asia."

Despite only 14 per cent seeing a significant advantage in a shift to EST, 45 per cent of business respondents said they supported the change. Another 30 per cent said they did not support the shift, while 25 per cent were undecided.

The ABC was among several media organisations, including channels Seven, Nine and Ten, that supported the shift forward to EST to overcome a half-hour delay to national programming.

An unnamed radio network, however, supported a half-hour shift in the opposite direction for the benefit of rural families and international economies.

West coast concerns 'dominate' submissions

The Government said responses from the state's west coast had dominated website and letter submissions, where a shift to EST means workers, teenagers and schoolchildren will be going to sleep in daylight and getting up in darkness throughout the year.

Mr Weatherill said two more pieces of work needed to be undertaken before the Government was in a position to make a judgement.

This included potential measures to minimise the impact on the west coast community, "including the option of a local, unofficial time".

Mr McBride said there was "absolutely no reason why the west coast community should suffer".

"We can change things like school times, working times, by regulation," he said.

"We've got plenty of flexibility to move that around."

Mr Weatherill said the potential effects of a shift to EST on Adelaide airport operations was the other key factor to be investigated.

Trade Minister Martin Hamilton-Smith said the aviation industry had raised concerns about the impact on flights.

The report cited a potential breach of the Adelaide Airport curfew by carrier Emirates and a need to revise airline schedules.

"One company said a late-departing flight could be impacted with an estimated loss of load factor of 20 per cent," Mr Hamilton-Smith said.

"Other airlines said their services would benefit from the changes.

"It is my intention to drill down further into these specific issues before coming back to Cabinet and the Parliament."

Mr Weatherill said the state's time zone could be changed to EST as soon as April 2017.

Opposition Leader Steven Marshall said the report gave no indication that a new time zone would lower SA's high unemployment rate.

"It's incredible that after spending eight months debating this issue, there's nothing incorporated in this report that suggests that one single solitary job is going to be created," he said.