Clarify your doubts by consulting your particular case
A settlement is deemed to be final in the following two cases:
a) When prior administrative verification of taxable transactions and its assessment is practiced, and has mediated or not a provisional settlement.
For example, the derivative of a final inspection report for any of the taxes
b) When it not has been ascertained within the period prescribed in the Act for each tax without prejudice to the prescription. For example, the income tax agreed upon with the reimbursement requested by the taxpayer (which implies the practice of provisional settlement), if the Administration does not perform the verification of tax, within the following five years on which the deadline for submitting the corresponding statement the provisional settlement "becomes" final.
The fundamental difference between the provisional and final settlements is that the latter, except in very exceptional circumstances, cannot be modified, while the provisional do allow new pronouncements by the Administration.
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