In the process of rebuilding its structures, the South African Revenue Service is reviewing its procurement processes and cancelling contracts that are not serving the institution.
The tax agency adopted numerous self-correcting measures following a damning report by the Nugent Commission of Inquiry, which found a "massive failure of governance and integrity" by SARS under former Commissioner Tom Moyane.
The Nugent Commission was established to probe matters of tax administration and governance at SARS.
"SARS is reviewing its procurement processes. Contracts that did not represent value for money have not been renewed," Treasury said in its Budget Review.
Treasury added that in the last 12 months under current Commissioner Edward Kieswetter, SARS had undertaken steps to "revive the institution", which had been impacted by allegations of maladministration that affected revenue collection and led to a haemorrhaging of skilled workers.
Several senior officials implicated by the Nugent Commission have left, while experienced staff have returned to roles from which they had been displaced.
SARS last year suspended three executives, including the Group Executive for Employment Relations, Luther Lebelo, and chief officer of governance, international relations strategy and communications, chief officer of governance, international relations strategy and communications, Hlengani Mathebula, who left the agency following the suspension.
In August, it suspended controversial IT head Mmamathe Makhekhe-Mokhuane, who later resigned.
In October, suspended chief officer of human capital and development Teboho Mokoena resigned with immediate effect. Mokoena had also been suspended.
Treasury said strengthening SARS would take time, but would result in improved revenue collection in the years ahead.
Tax revenue is projected to grow by 4.9% in 2020/21, while gross tax buoyancy is expected to slip to 0.93%, due to lower personal income tax receipts following the anticipated reduction in the public service wage bill.
"Efficiency improvements at SARS may bolster revenue further, but such potential gains are not included in the current projections," Treasury said.
Other measures adopted by SARS include the re-launched the Large Business Centre, which is responsible for collecting tax from corporate companies - the third-largest revenue contributor. The critical unit had been dismantled under Moyane's administration.
Treasury noted that recovery of SARS has not taken pace at the same rate as the economy, but revenue is expected to improve over the medium term as growth recovers.