New research has revealed that South Africa's congested border posts are costing the economy up to R16 billion annually, with experts warning that inefficient crossings are threatening exports, investment and the country's role as Africa's logistics hub.

South Africa is losing between R15 billion and R16 billion every year because of congestion at key border posts, with logistics experts warning that prolonged delays are undermining the country's competitiveness, raising consumer prices and threatening its ambitions of becoming Africa's regional trade hub.

The warning follows research presented at the 44th Southern African Transport Conference, where a study by Carla Meyer and Dr Johann van Rensburg of Stellenbosch University quantified the financial impact of delays at Lebombo, Beitbridge, Groblersbrug and Vioolsdrift.

The findings come as increasing volumes of freight continue shifting from South Africa's constrained rail and port network onto roads, placing greater pressure on border infrastructure.

Serialong 'Seri' Kumalo, Communications and PR Consultant for the Southern African Transport Conference, said the headline figure represented only part of the economic damage.