For the next two financial years (2012/2013 and 2013/2014), the cap on concessional contributions aka pre-tax contributions into super is limited to $25,000. The pre-tax cap includes salary sacrifice amount but also employer contributions therefore care must be taken when salary sacrificing so that total pre-tax super contributions do not exceed $25,000 in a financial year otherwise penalty tax may be applied and the contribution above the cap taxed at 46.5%. People who received bonuses and commissions should also be careful as some employers will pay the 9% superannuation guarantee amount on bonuses and commissions and if not taken into account, may push you over the $25,000 limit if you already salary sacrifice. An extract from the article:

“People wanting to take full advantage of the $50,000 cap should check what their super guarantee and salary sacrifice contributions are to date and make sure any extra they put in doesn’t exceed the $50,000, says PSK Financial Services adviser James Gerrard. From July 1, the concessional contribution cap will be $25,000 for everyone – at least for the next two years.”

Read the full article here:
How to beat the super tax traps – Australian Financial Review (Bina Brown 9/6/12)