Fiji's People's Democratic Party says political parties' campaigns have been compromised after surprise plans for pre-polling which begins tomorrow.
The Elections Office says about 66,000 voters are due to cast their vote at 547 polling venues over the next two weeks.
The military and those in remote areas are among those who have to vote early.
The PDP's Aman Ravindra Singh says the first his party knew of plans for early voting was when they saw notices in the newspaper just over a week ago.
"Obviously if we knew about all these areas which would have pre-polling starting on the 3rd then we would have reached them first as a matter of priority but campaigning continues and we have yet to reach some of these interior areas and all of a sudden polling will be taking place in these areas. It shows the chaos in the Supervisor of Elections office."
Mr Ravindra Singh says when he told people in the mountains near Tavua at the weekend they had to vote early, they were shocked by the news.
The Fijian Elections Office has called for local officials in pre-polling areas to make sure voters are aware.