Salary sacrificing is where you make extra regular voluntary contributions, or, contribute a one-off amount from your before tax income into your superannuation.
Salary sacrificing can help to grow your super at an accelerated rate. When you salary sacrifice you generally only pay 15 per cent tax on these contributions instead of your marginal tax rate (plus Medicare levy and other applicable levies). Refer to Division 293 tax section on the ATO website.
There is a limit of $27,500 that you can contribute to super from your before-tax income in any one year. This limit includes your employer contributions.
For more information on how you can salary sacrifice, speak to your employer who can arrange this for you, or visit the ATO website.