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Partnership & S Corporation Apportionment


Apportionment Requirements

Income is generally apportioned in one of two ways:

  • Single-sales factor
  • Colorado sourced income of nonresident individuals method

Single-Sales Factor

Income is generally apportioned using the single-sales method. When using single-sales method of apportionment, all business income must be apportioned using the single-sales factor. Non-business income may either be directly allocated to the appropriate state or treated as business income, subject to the single-sales factor apportionment. Complete and include Part IV of the DR 0106 with your return if you are apportioning income using the single-sales factor apportionment method.


Colorado-Sourced Income of a Nonresident