You will be regarded as a non-resident if you have been in Singapore for less than 183 days in a calendar year.
As a non-resident,
You will only be taxed on all income earned in Singapore
You will not be given personal reliefs
Your employment income will be taxed at a flat rate of 15% or the resident rates for the Year of Assessment 2007, depending on which gives a higher tax. See example below.
For director’s fees and income other than employment, they will be taxed at a flat rate of 22% for the Year of Assessment 2004 (20% from Year of Assessment 2005).
Example - Tax Computation for a Non-Resident for the Year of Assessment 2007
