The ATO advises that the bilateral social security agreement with Hungary started on 1 October 2012. The agreement can also apply to people sent to Hungary or Australia for work before this time, but only for superannuation guarantee (SG) contributions (or equivalent) made on or after 1 October 2012.
The agreement only applies where double super coverage occurs. That is, when an employer or their employee must make SG contributions (or equivalent) under both Australian and Hungarian law for the same work undertaken by the employee.
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