Determination of the taxable base (page 13 of Form 200)
To determine the taxable base in the corporate income tax settlement (box ), entities that apply the special regime for shipping entities based on tonnage:
The sum of the following boxes should be transferred to box  "Taxable income before capitalisation reserve and offsetting of tax losses" on page 13 of form 200:
In box  "Taxable base of activities or income taxed under the general system" on page 13 of form 200, the part of the taxable base corresponding to the activities not subject to the special system shall be entered.
They will be determined by applying the general corporate income tax system, taking into account only the income derived therefrom.
To do so, these entities must perform the following operation:
 =  +  - 
For these purposes, it should be noted that in order to obtain the amounts corresponding to boxes  and  "Total corrections to the profit and loss account result" on page 13 of form 200, the shipping entities must have computed the respective amounts of the relevant increases and decreases and, in any case, the amount of boxes  or  "Regime for shipping entities according to tonnage (Chapter XVI of Title VII LIS)" (as appropriate and as indicated in the previous section with respect to both boxes).
The amount obtained for box  must be entered in that box in any case, even if the result is zero or negative and, in the latter case, preceded by a minus sign (-).
If the amount in box  is negative the sum of boxes  and  shall not be added, and the amount in box  shall be transferred directly to box .
In the box  "Taxable base derived from the application of the special scheme" on page 13 of form 200, enter the part of the taxable base corresponding to the operation, ownership and, where applicable, technical and crew management, of vessels covered by the special scheme.
To obtain the amount to be entered in this box, the specific table "Regime of shipping entities according to tonnage" on page 21 of form 200 must first be filled in as detailed above (to find out how to fill in this table, see the following section ).
If these entities have entered in the box  "Taxable income before capitalisation reserve and compensation of tax losses" on page 13 of form 200, a positive amount resulting from the sum of the amounts in the boxes  "Taxable income from activities or income taxed under the general system" and  "Taxable income derived from the application of the special system", may compensate negative taxable income from previous years in the following way:
The total amount of tax losses to be offset in the tax period subject to assessment, entered in box  on page 15 of form 200 (resulting from filling in the table "Details of offset of tax losses"), must be transferred to the same box on page 13 of form 200, but reduced by the amount entered in box  "Offset of tax losses from previous periods" on page 21 of the form.
Shipping entities taxed under this special regime, when completing the table "Details of the offset of tax losses" on page 15 of form 200 (see how to complete this table in Chapter 5 of this Practical Manual), unlike other entities, must not simply transfer the amount in box  of this table to the same box on page 13 of form 200, but must first reduce the total entered in box  on page 15 of form 200 by the amount entered in box  on page 21 of form 200, and the amount resulting from this reduction must be the amount entered in box  on page 13 of form 200.
The amount entered in box  on page 13 of form 200 should be subtracted from the amount entered in box , but bearing in mind that the maximum amount by which the amount in box  can be reduced by is the amount shown in box .
Finally, the amount resulting from subtracting box  from box , which may not be negative, shall be entered in box  "Taxable base" on page 13 of form 200.