During Wednesday's by-elections, the ANC and DA retained the wards they previously held.
In the case of the DA, this is in contrast to recent by-election results in various regions after the May 2019 national elections, in which the party bled support.
For instance, in the September by-elections, in four of the five wards the DA held in which by-elections were contested, its support dropped more than 20 percentage points, causing the party to lose two wards, one to the ANC and one to the FF Plus.
In Wednesday's by-elections, the DA retained Ward 2 in the Blue Crane Municipality in the Eastern Cape, with 53.45% of the vote. In 2016, it got 59.09% of the vote.
At the by-election at the Msunduzi Municipality, which includes the regional hub Pietermarizburg, the DA held its ward and increased its support with two percentage points from 44.04% in 2016 to 46.94%.
DA spokesperson Solly Malatsi said the results are encouraging and show their offer still resonates with many South Africans.
"We hope we can continue to build on this momentum going into the next series of by-elections."
The next by-elections will take place next week.
Meanwhile, it was a bit of a mixed bag for the ANC, with its support remaining strong in the Eastern Cape, but seemingly waning in KwaZulu-Natal.
The party's support remained around the 94% mark in the ward Ngqushwa in the Eastern Cape, and it showed a 20 percentage points increase in the by-election in Umzimvubu, also in the Eastern Cape, surging from 76.15% in 2016 to 96.61% on Wednesday.
At Umzumbe in KwaZulu-Natal, it dropped almost 30 percentage points, from 89.23% in 2016 to 60.74% on Wednesday.
In Mpofana, also in KwaZulu-Natal, the ANC lost 13 percentage points compared to 2016, dropping from 53.29% to 40.08%.
The drop in support was less marked in Kwadukuza, where the party dropped from 59.18% to 57.53%.
ANC KwaZulu-Natal spokesperson Ricardo Mthembu in a statement thanked the voters who help them retain their wards.
"These results are a clear indication that the people appreciate our efforts to reconnect with them and we commit ourselves to redouble our efforts to address the challenges they face," he said.
"We congratulate the DA for its victory in Msunduzi and also congratulate the IEC (Electoral Commission of SA) for delivering a credible, free and fair elections."