Around three in four people wishing to attend the Anzac centenary event at Gallipoli in 2015 will miss out, with demand far outstripping the number of tickets available.
Nearly 30,000 people have entered the ballot to attend the commemoration in Turkey, but only 8000 tickets are available for Australians.
The ballot closes at midnight on Friday.
"I know there will be a lot of disappointed people," minister assisting the prime minister for the Centenary of Anzac senator Michael Ronaldson told ABC TV on Friday.
The 8000 tickets includes 6000 general admission spots, 800 for direct descendants, 800 for veterans and 400 for school children and their guardians.
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Senator Ronaldson said the Australian government had also offered to pay for 160 widows of World War One veterans to attend.
"I'd like to think as many as possible could come. They are a very special group," he said.
He said it wouldn't be a "pollie fest" as only himself, his Labor counterpart, opposition leader Bill Shorten and Prime Minister Tony Abbott would be attend.
