Election. If an election is made under section 4(a) of the Act and if the net increase in tax determined in accordance with paragraph (b) of this section exceeds $2,500, the taxpayer may also make an election under section 4(b) of the Act prior to September 1, 1960, to pay any portion of such net increase in tax, unpaid on the date of the election, in 2 or more, but not to exceed 10, equal annual installments. If the taxpayer making the election under section 4(a) of the Act is a partnership or a small business corporation electing under Subchapter S, Chapter 1 of the Code, the determination as to whether the net increase in tax exceeds $2,500 shall be made separately as to each partner or shareholder, respectively, with regard to his individual liability. Thus, if a partnership makes an election under section 4(a) of the Act, and partners A and B had a net increase in tax of $3,000 and $2,000, respectively, as a result of dealer reserve income adjustments to partnership income, partner A may elect under section 4(b) of the Act to pay the net increase in 2 or more, but not exceeding 10, equal annual installments to the extent that such tax was unpaid on the date of the election. Partner B may not make the election since his net increase in tax does not exceed $2,500.

Net increase in tax. (1) The term “net increase in tax” means the amount by which the sum of the increases in tax (including interest) for all taxable years to which the election under section 4(a) of the Act applies and which is attributable to the election exceeds the sum of the decreases in tax (including interest) for all taxable years to which the election under such section applies and which is attributable to the election.

In determining the net increase in tax, the tax and interest for each taxable year to which the election applies is computed by taking into account all adjustments necessary to reflect the change to the proper treatment of dealer reserve income. If the computation results in additional tax for a taxable year, then interest is computed under section 6601 of the Code (or corresponding provisions of prior law) on such additional tax for the taxable year involved from the last date prescribed for payment of the tax for such taxable year to the date the election is made. The interest so computed is then added to the additional tax determined for such taxable year. The sum of these two items (tax plus interest) represents the increase in tax for such taxable year. If the computation of the tax after taking into account the appropriate dealer reserve income adjustments results in a reduction in tax for any taxable year to which the election applies, interest under section 6611 of the Code (or corresponding provisions of prior law) is computed from the date of the overpayment of the tax for such year to the date of the election. The amount of the interest so computed is then added to the reduction in tax to determine the total decrease in tax for such year. The net increase in tax is then determined by adding together the total increases in tax for each year to which the election applies and from the resulting total subtracting the sum of the total decreases in tax for each year. If the total increases in tax for all such years do not exceed the total decreases in tax, there is no net increase in tax for purposes of section 4(b) of the Act. For purposes of determining the net increase in tax, net operating losses affecting the computation of tax for any prior taxable year not otherwise affected shall be taken into account.

Time for paying installments. If the election under this section is made to pay the unpaid portion of the net increase in tax in installments, the first installment shall be paid on or before the date prescribed by section 6151(a) of the Code for payment of the tax for the taxable year in which such election is made. Each succeeding installment shall be paid on or before the date which is one year after the date prescribed for the payment of the preceding installment.

Termination of installment privilege—(1) For nonpayment of installment. The extension of time provided by section 4(b) of the Act for payment of the net increase in tax in installments shall terminate, and any unpaid installments shall be paid upon notice and demand from the district director if any installment under such section is not paid by the taxpayer on or before the date fixed for its payment, including any extension of time for payment of any such installment.

For other reasons. The extension of time provided by section 4(b) of the Act for payment of the net increase in tax in installments shall terminate, and any unpaid installments shall be paid upon notice and demand from the district director if:

In the case of an individual, he dies or ceases to engage in any trade or business,

In the case of a partner, his entire interest in the partnership is transferred or liquidated or the partnership terminates, or

In the case of a corporation, it ceases to engage in a trade or business, unless the unpaid portion of the tax payable in installments is required to be taken into account by an acquiring corporation under section 5(d) of the Act.

Redetermination of tax subsequent to exercise of installment election. Section 4(d) of the Act provides that where a taxpayer has elected to pay the net increase in tax in installments and thereafter it becomes necessary to redetermine the taxpayer's tax for any taxable year to which the election provided by section 4(a) of the Act applies, then the net increase in tax shall be redetermined. Where the redetermination does not involve adjustments affecting the treatment of dealer reserve income, then the net increase in tax previously computed will not be disturbed. The net increase in tax is limited to the amount of tax computed under section 4(b)(2) of the Act as a result of the change in treatment accorded dealer reserve income. If the redetermination of tax for any taxable year to which the election applies results in an addition to the net increase in tax previously computed, then such addition shall be prorated to all of the installments whether paid or unpaid. The part of the addition, prorated to installments which are not yet due, shall be collected at the same time as, and as a part of, such installments. The part of the addition prorated to installments, the time for payment of which has arrived, shall be paid upon notice and demand from the district director. Under section 4(g) of the Act, failure to make such payment within 10 days after issuance of notice and demand will terminate the installment privilege. The imposition of interest on the addition to the net increase in tax as a result of the redetermination will be determined in the same manner as interest on the previously computed net increase in tax. Thus, no interest will be imposed on the amount of the addition to the net increase in tax prorated to installments not yet due unless the installment privilege is terminated under subsection (f) or (g) of section 4 of the Act. If a reduction in the net increase in tax results from a redetermination of tax for any taxable year to which the election applies, the entire amount of such reduction shall, in accordance with the provisions of section 6403 of the Code (relating to overpayment of installments), be prorated to the installments which are not yet due, resulting in a pro rata reduction in each of such installments. Where the redetermination does not involve adjustments pertaining to dealer reserve income, then any resulting deficiency pertaining to the year to which the election applies will be assessed and collected, in accordance with the applicable provisions of the Code (or corresponding provisions of prior law) without regard to any election made under the Act.

Periods of limitation. Section 4(h) of the Act provides that where there is an extension of time for payment of tax under the provisions of section 4(b) of the Act, the running of the periods of limitation provided by section 6502 of the Code (or corresponding provisions of prior law) for collection of such tax is suspended for the period of time for which the extension is granted.