(a) Except as otherwise provided in this section, a notice of deficiency, as provided in section 63-3045, Idaho Code, for the tax imposed in this chapter shall be issued within three (3) years from either the due date of the return, without regard to extensions, or from the date the return was filed, whichever is later.
(b) If an assessment has been made as provided in this chapter, then such tax shall be collected either by levy, or by a proceeding brought in court, within a period of twelve (12) years from the date of entry of the record of assessment required by section 63-3045A, Idaho Code, of the tax and provided, further, that this shall not be in derogation of any of the remedies elsewhere provided in this chapter.
(c) In the case of a fraudulent return or a false return with the intent to evade the tax imposed in this chapter, or a willful attempt in any manner to defeat or evade the tax imposed in this chapter, a notice of deficiency may be issued, the tax may be assessed, or a proceeding in court for collection of such tax may be begun without assessment, at any time.
(d) In the case of a failure to file a return, for any reason, a notice of deficiency may be issued, the tax imposed in this chapter may be assessed, or a proceeding in court for collection of such tax may be begun without assessment, at any time, unless the taxpayer had a reasonable belief that no return was required to be filed under this chapter, in which case any deficiency, assessment, or proceeding for collection of such tax shall be commenced within three (3) years of the time the return was due.
(e) In the case of income received during the lifetime of a decedent, or by his estate during the period of administration, a notice of deficiency shall be issued, a claim shall be made, the tax shall be assessed or any proceeding in court without assessment for the collection of such tax shall be begun, within twelve (12) months after written request for prompt action is filed with the state tax commission by the executor, administrator, or other fiduciary representing the estate of such decedent. This subsection shall not apply if the return for which the request for prompt action relates has not been filed with the state tax commission.
(f) When Idaho taxable income or tax credits for any taxable year have been adjusted as a result of a final federal determination, the period of limitation for issuing a notice of deficiency shall be reopened and shall not expire until the later of one (1) year from the date of delivery of the final federal determination to the state tax commission by the taxpayer, three (3) years from the due date of the return, without regard to extensions, or three (3) years from the date the return was filed. For purposes of this subsection the term "final federal determination" shall mean the final resolution of all issues which were adjusted by the internal revenue service. When the final federal determination is submitted, the taxpayer shall also submit copies of all schedules and written explanations provided by the internal revenue service. Upon the expiration of the period of limitations as provided in subsections (a) and (m) of this section, only those specific items of income, deductions, gains, losses, or credits which were adjusted in the final federal determination shall be subject to adjustment for purposes of recomputing Idaho income, deductions, gains, losses, credits, and the effect of such adjustments on Idaho allocations and apportionments.
(g) If an adjustment, which was made within the period of limitations as provided in this section, affects the amount of tax credit, net operating loss, or capital loss, claimed in a taxable year other than the tax year in which the adjustment is made, then adjustments to the credit, net operating loss, or capital loss claimed in such other tax year may be made and a resulting notice of deficiency may be issued even though such notice of deficiency would otherwise be barred under the provisions of this section.
(h) Notwithstanding any other provisions of this section, when an amended Idaho return is filed within the period of limitations as provided in subsections (a) and (m) of this section, the period of limitations for issuing a notice of deficiency shall be three (3) years from the date the amended return was filed. However, upon the expiration of the period of limitations as provided in subsections (a) and (m) of this section, only those specific items of income, deductions, gains, losses, or credits, which were adjusted in the amended Idaho return shall be subject to adjustment for purposes of recomputing Idaho income, deductions, gains, losses, credits, and the effect of such adjustments on Idaho allocations and apportionments.
(i) If a taxpayer has filed an amended federal return, and no corresponding Idaho amended return has been filed with the state tax commission, then the period of limitations for issuing a notice of deficiency shall be reopened and shall not expire until three (3) years from the date of delivery to the tax commission by the taxpayer of the amended federal return. However, upon the expiration of the period of limitations as provided in subsections (a) and (m) of this section, then only those specific items of income, deductions, gains, losses, or credits, which were adjusted in the amended federal return shall be subject to adjustment for purposes of recomputing Idaho income, deductions, gains, losses, credits, and the effect of such adjustments on Idaho allocations and apportionments.
(j) Notwithstanding any other provisions of this section, a notice of deficiency, related to items on the return of any pass-through entity, as defined in this section, which other taxpayers are required by law to report, shall be issued to such other taxpayers within the later of three (3) years from the due date of the other taxpayers’ return, without regard to extensions, three (3) years from the date the other taxpayers’ returns were filed, or three (3) years from the date of filing of the pass-through entity’s return. If the pass-through entity files an amended return, notices of deficiency may be issued to the other taxpayers within three (3) years from the date the amended return for the pass-through entity was filed with the state tax commission. If the pass-through entity files an amended return with the internal revenue service, or the internal revenue service issues a final determination to the pass-through entity, then the period of limitations for issuing a notice of deficiency to the other taxpayers shall be reopened and shall not expire until three (3) years from the date of delivery to the tax commission by the pass-through entity of the amended federal return or the later of one (1) year from the date of delivery to the state tax commission by the pass-through entity of the final federal determination, three (3) years from the due date of the pass-through entity’s return, without regard to extensions, or three (3) years from the date the pass-through entity’s return was filed.
(k) For purposes of this section, "pass-through entity" means a partnership, S corporation, trust, limited liability company or any other entity whose items of income, deductions, gains, losses and credits must be reported by other taxpayer(s). For further purposes of this section, the term "other taxpayer" shall include, by way of unlimiting example, such taxpayers as partners, shareholders, beneficiaries, joint venturers or investors.
(l) In the case of a duplicate return filed under section 63-217 (1)(b), Idaho Code, the limitation under this section shall be the later of one (1) year from the filing of the duplicate return or the date otherwise applicable under this section.
(m) Prior to the expiration of the time prescribed in this section for the issuance of a notice of deficiency for the tax imposed in this chapter, both the state tax commission, its delegate or deputy, and the taxpayer may consent in writing to extend the period of time within which a notice of deficiency may be issued. The period so agreed upon may be extended by subsequent agreements in writing made before the expiration of the period previously agreed upon. When a pass-through entity extends the period of limitations in accordance with this subsection, the period of limitations for the other taxpayers is automatically extended for the same period for the purpose of issuing a notice of deficiency to the other taxpayers reflecting the adjustments to the pass-through entity’s return.
(n) The expiration of the period of limitations as provided in this section shall be suspended for the time period during which the state tax commission is prohibited from issuing a notice of deficiency, making the assessment, or from collecting by levy or a proceeding in court, and for thirty (30) days thereafter.
(o) For the purposes of this section, "return" includes a notice of deficiency determination issued by the state tax commission when no return was filed by the taxpayer. Such a return is deemed filed on the date the taxes determined by the state tax commission are assessed.