(a) When the assessment of a tax imposed by this title has been made within the period of limitation under AS 43.05.260, the tax may be collected by levy or by a proceeding in court, but only if the levy is made or the proceeding is begun (1) within six years after the assessment of the tax; or (2) before the expiration of a period for collection agreed upon in writing by the department and the taxpayer before the expiration of the six-year period; a period agreed upon may be extended by subsequent agreements in writing made before the expiration of the period previously agreed upon; the period provided by this paragraph during which a tax may be collected by levy may not be extended or curtailed because of a judgment against the taxpayer. (b) The date on which a levy on property or right to property is made is the date on which the notice of seizure is given.
Alaska Legal Code