South African Airways will downgrade a direct service between Cape Town and London to a one-stop flight in Johannesburg starting on 15 August.
At the same time, the Star Alliance carrier will up-guage its capacity by 13% between Johannesburg and London Heathrow, or about 30 seats per aircraft.
There is currently a nearly 30-seat difference on the two flights South African Airways operates between Johannesburg and London Heathrow. Both a 222-seat Airbus A320-200 and a 253-seat A340-300 operate six weekly frequencies on the route.
The change means South African Airways is withdrawing from a direct competition with British Airways on direct service from London Heathrow to Cape Town International airport.
British Airways currently flies a 315-seat Boeing 747-400 daily between Cape Town and London Heathrow.
Until 15 August, South African Airways is operating five flights weekly on a 222-seat Airbus A330-200 on the same route. The airline launched the route in 1992.
"A thorough analysis of the route made it clear that we could use our aircraft more profitably elsewhere," says Theunis Potgieter, general manager of commercial for South African Airways, in a press statement.
The statement also implied that fees imposed by the UK government contributed to the route change.
"Since , numerous international airlines have added [Cape Town] to their routes, among then airlines based in oil producing states whose structures give them a lower overall cost base, and whose home countries - unlike the UK - do not charge South Africans for transit visas," South African Airways says.