Tax in Hong Kong on income is progressive, with rates from 2-17%, although the standard rate of tax is 16% (2008). Allowances for single parents, married couples and for the number of dependent children reduce the taxable amount from the total of salary.
Depending on when you start working, you may get your first tax bill 18 months later. Bear in mind the amount of outstanding tax you owe or the bill can be a shock. A good idea is to put it in a separate account every month. Your normally get an assessment notice from the Inland Revenue Department (IRD) in autumn with the sum due.
For more information on tax declarations, check out the IRD website at www.ird.gov.hk. It also offers an automatic salary tax computation service. Make sure to keep the IRD up to date with changes to your address and to inform them immediately in case of delayed payment. A surcharge of 5% is normally automatically added to late payments.