The tax base of some taxpayers may be determined under a presumptive method in any of the following:
1- The taxpayer has no reliable accounts to determine the tax base.
2- The Department has not accepted the taxpayer’s books due to essential

     shortfalls in them.
3- The taxpayer has failed to make timely filing of the return.
4- Branches of foreign air and sea transport companies operating in the Kingdom

     that can not prove their tax base according to the provisions of the Income 

     Tax Law.

   The rate used to determine the tax base is different from one activity to another depending on conditions of each case and on other indicative factors. However, the rate will never be less than 15 percent of the taxpayer’s gross receipts. Tax base of some special activities are determined as follows:

     - Professionals, such as medical doctors, lawyers, accountants and engineers

       at a minimum rate of 20 percent of income.
     - Technical and consulting services at a minimum rate of 20 percent.
     - Management fees at a rate of 80 percent.
     - Payments for using intangible rights, such as royalties, concession rights,

       and patents at a rate of 75 percent.
 

  Branches of foreign air and sea transport companies at a minimum rate of 5 percent of income realized in the Kingdom from tickets, luggage, freight, mail and any other income.

   This treatment and the estimated rates shall not apply to taxpayers subject to withholding tax.