Do you pay SGC on the component of wages reduced by salary sacrifice?

The calculation of SGC has now changed as at 1 January 2020.

The minimum amount of super guarantee employers are required to pay in relation to your employee is based on their ordinary time earnings. Salary sacrifice no longer reduces your employee's OTE, so you are required to pay the super guarantee on wages including any salary sacrifice components.

https://www.ato.gov.au/Business/Super-for-employers/In-detail/Salary-sacrifice/Salary-sacrificing-super---information-for-employers/?page=5