The strike came at the peak of the vacation season, with protests from municipal and store workers joining the labour action in other sectors and taking their plight to the streets on Wednesday.
Police reinforcements were sent to major city centres, as thousands of demonstrators - many reportedly armed with sticks and dumping trash on the streets - marched towards local government offices.
The common thread in all the industrial action was growing anger at the widening salary gulf between executives and workers, most of whom struggle to pay for basics such as housing and food on monthly wages of less than 3000 rands ($449).
The Commission for Conciliation, Mediation and Arbitration said airline management and unions would meet again on Thursday with their response to a proposed agreement, hammered out in tough negotiations to end the six-day strike that has grounded all international and most domestic flights and stranded thousands of passengers.
"Significant progress has been made toward resolution of the dispute," the mediation body said in a statement. "In principle, agreement has been drafted, the contents of which cannot be disclosed at this stage."
One of the unions involved - the United Association of SA - said it would recommend acceptance to its members.
"In principle, agreement has been drafted, the contents of which cannot be disclosed at this stage"
Commission for Conciliation, Mediation and Arbitration
There was no immediate word from two unions representing cabin crew and ground staff.
Pilots have not joined the strike but indicated they too might resort to industrial action if their wage demands were not met.
The unions have demanded an 8% salary raise, while management has offered a 5% raise plus increases in medical and housing benefits and a one-time payment of 1600 rands ($239).
The airline says its resources are limited due to rising oil costs and the need to keep pay settlements within the inflation rate.
But staff point out that the airline made 966 million rand ($144 million) in profit last year and could share some of the proceeds with the work force.
There also has been criticism of the airline's management under new Chief Executive Officer Khaya Ngqula, who attended a function at a luxury game reserve near the Kruger National Park in the early stages of the strike, leaving his subordinates to deal with angry passengers.
Economists estimate the strike has cost the airline 25 million rands ($3.7 million) a day, with similar losses suffered by the tourist industry.
About 2000 passengers are
stranded in South African hotels
The airline has managed to transfer about two-thirds of its passengers to other carriers, but 2000 passengers remained stranded in hotels in Johannesburg and other countries.
"We are sorry," read a one-page SAA advertisement in newspapers on Wednesday. "The past few days have been the most difficult in the history of our airline."
Meanwhile, chaos was reported at some public taxi stands after the cancellation of bus services, as municipal workers began a three-day strike to demand a 9% wage increase and a new minimum wage of 3000 rands ($449) a month.
Their employer, the SA Local Government Association, has offered 6%, which unions dismissed as "ridiculously low".