STORY: Voting was underway on Wednesday (May 29) in South Africa's most competitive election since the end of apartheid.

Opinion polls suggest the ruling African National Congress is heading for a first-ever loss of its parliamentary majority in 30 years of government.

The significance of the day is not lost on first time voter Naledi in Cape Town.

"I understand that it's a very important decision to make. So yes, I'm excited but very nervous because it is a very big decision, yeah. Thirty years of democracy is a very long way that we've come, so I just want to continue to help our country get to a better place."

If the ANC does fall short of 50% of the vote then it will need to make a deal with one or more smaller parties to govern.

Opposition parties in this vote include the pro-business Democratic Alliance, the Marxist Economic Freedom Fighters and the newly formed MK Party led by former president Jacob Zuma.

Voters are electing assemblies in each of South Africa's nine provinces and a new national parliament which will then choose the next president.

The ANC is still expected to pick up the biggest share of votes.

And that means incumbent President Cyril Ramaphosa is likely to stay in office unless he faces an internal challenge.

However, this election does look set to mark a major political shift in a country that has been dominated by a single party for decades.

The ANC's gradual fall from grace has been driven by dissatisfaction over high rates of unemployment and crime, frequent power blackouts and corruption in party ranks.

More than 27 million South Africans are registered to vote and the electoral commission is expected to start releasing partial results within hours of polling stations closing.