President Cyril Ramaphosa signed a law on Friday requiring political parties to disclose donations of more than R100 000 in a bid to clean up party funding, but it did not ban anonymous donations.
The Political Party Funding Act requires parties to make bank statements available from donations that size or greater.
In addition, it "prohibits donations to parties by foreign governments or agencies, foreign persons or entities, organs of state or state-owned enterprises", a statement from his office said, apart from funding for training or policy development.
Whether it is drug money sloshing through Latin American elections, wealthy individuals in Western nations making hefty donations in exchange for government contracts, or African patronage networks influencing power, there is a growing global recognition that wealth subverts democracy when unregulated.
But South Africa was one of the few democracies that had no regulation at all on private political party funding before this bill came into effect. That enabled wealthy people and companies to pull strings behind the scenes.
"The Political Party Funding Act will.. strengthen the confidence of citizens in the democratic political process," Ramaphosa said in a statement.
Sheilan Clarke, of MyVoteCounts, a national campaign to improve transparency in elections, welcomed the move, but said there were many loopholes in the law.
"One is that donors can still donate anonymously," she said, as they can still use bank accounts that hide the true source of the money. "But we'll have the numbers...which is better than anything we've had since the arrival of democracy (in 1994)".
Another bill, Promotion of Access to Information Act amendment, which Ramaphosa has yet to sign, will force parties to publish their donations and the associated paper trail themselves - but again, it does not prevent anonymity.
"If you look the state of corruption...in South Africa, they were able to get away with it because there's no way for us to see," Clarke said. "This will do away with that secrecy."