Rev. & Tax. Code, § 6591.5 · Article 6. Interest and Penalties
Rev. & Tax. Code, § 6591.5
Text — As published in the Legislative Counsel's database, tables dated October 18, 2026 (pubinfo_2025.zip)
(a) (1) For interest required to be paid to the state upon underpayments of tax to the state, “ modified adjusted rate per annum” means the adjusted annual rate established pursuant to subdivision (c), plus three percentage points.
(2) For interest required to be paid by the state upon overpayments of tax, “modified adjusted rate per annum” means the adjusted annual rate established pursuant to subdivision (d).
(b) “Modified adjusted rate per month, or fraction thereof” means the modified adjusted rate per annum divided by 12.
(c) The rate established for interest to be paid upon underpayments of tax shall be determined in accordance with the provisions of Section 6621 of the Internal Revenue Code which establish the underpayment rate, except that the determination specified in Section 6621(b) of the Internal Revenue Code shall be modified to be determined semiannually as follows:
(1) The rate for January shall apply for the following July 1 to December 31, inclusive.
(2) The rate for July shall apply for the following January 1 to June 30, inclusive.
(d) (1) Except as provided in paragraph (2), the rate established for interest to be paid by the state upon overpayments of tax shall be equal to the bond equivalent rate of 13-week treasury bills auctioned, rounded to the nearest full percent (or if a multiple of one-half of 1 percent, the rate shall be increased to the next highest full percent), as follows:
(A) The bond equivalent rate of 13-week treasury bills established at the first auction held during the month of January shall apply for the following July 1 to December 31, inclusive.
(B) The bond equivalent rate of 13-week treasury bills established at the first auction held during the month of July shall apply for the following January 1 to June 30, inclusive.
(2) For the period July 1, 1991, through June 30, 1992, the rate to be paid by the state upon overpayments of tax shall be equal to the bond equivalent rate of 13-week treasury bills established at the auction held on July 1, 1991, rounded to the nearest full percent (or if a multiple of one-half of 1 percent, the rate shall be increased to the next highest full percent).
(e) For purposes of this part, and any other provision of law referencing this method of computation, in computing the amount of any interest required to be paid by the state or by the taxpayer, or any other amount determined by reference to that amount of interest, that interest and that amount shall be computed as simple interest, not compound interest.
Notes and commentary — not statutory text
History
Amended by Stats. 1991, Ch. 236, Sec. 5.2. Effective July 29, 1991.
Source of truth
- Edition
- As published in the Legislative Counsel's database, tables dated October 18, 2026 (pubinfo_2025.zip)
- Official file
- https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=RTC§ionNum=6591.5.
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Cited by 132 provisions
Provisions in this library whose text cites Rev. & Tax. Code, § 6591.5; the first 50 in book order. Each shows the citation as that text prints it.
Revenue and Taxation Code
- Rev. & Tax. Code, § 6072Printed as Section 6591.5
- Rev. & Tax. Code, § 6459Printed as Section 6591.5
- Rev. & Tax. Code, § 6479.3Printed as Section 6591.5
- Rev. & Tax. Code, § 6480.4Printed as Section 6591.5
- Rev. & Tax. Code, § 6482Printed as Section 6591.5
- Rev. & Tax. Code, § 6513Printed as Section 6591.5
- Rev. & Tax. Code, § 6591Printed as Section 6591.5
- Rev. & Tax. Code, § 6591.6Printed as Section 6591.5
- Rev. & Tax. Code, § 6592.5Printed as Section 6591.5
- Rev. & Tax. Code, § 6907Printed as Section 6591.5
- Rev. & Tax. Code, § 6936Printed as Section 6591.5
- Rev. & Tax. Code, § 7157Printed as Section 6591.5
- Rev. & Tax. Code, § 7655Printed as Section 6591.5
- Rev. & Tax. Code, § 7655.5Printed as Section 6591.5
- Rev. & Tax. Code, § 7656Printed as Section 6591.5
- Rev. & Tax. Code, § 7659.9Printed as Section 6591.5
- Rev. & Tax. Code, § 7661Printed as Section 6591.5
- Rev. & Tax. Code, § 7674Printed as Section 6591.5
- Rev. & Tax. Code, § 7706Printed as Section 6591.5
- Rev. & Tax. Code, § 7727Printed as Section 6591.5
- Rev. & Tax. Code, § 8130Printed as Section 6591.5
- Rev. & Tax. Code, § 8151Printed as Section 6591.5
- Rev. & Tax. Code, § 8407Printed as Section 6591.5
- Rev. & Tax. Code, § 8754Printed as Section 6591.5
- Rev. & Tax. Code, § 8760Printed as Section 6591.5
- Rev. & Tax. Code, § 8777Printed as Section 6591.5
- Rev. & Tax. Code, § 8803Printed as Section 6591.5
- Rev. & Tax. Code, § 8876Printed as Section 6591.5
- Rev. & Tax. Code, § 8876.5Printed as Section 6591.5
- Rev. & Tax. Code, § 9155Printed as Section 6591.5
- Rev. & Tax. Code, § 9174Printed as Section 6591.5
- Rev. & Tax. Code, § 12258Printed as Section 6591.5
- Rev. & Tax. Code, § 12287Printed as Section 6591.5
- Rev. & Tax. Code, § 12307Printed as Section 6591.5
- Rev. & Tax. Code, § 12631Printed as Section 6591.5
- Rev. & Tax. Code, § 12631.5Printed as Section 6591.5
- Rev. & Tax. Code, § 12632Printed as Section 6591.5
- Rev. & Tax. Code, § 12983Printed as Section 6591.5
- Rev. & Tax. Code, § 13107Printed as Section 6591.5
- Rev. & Tax. Code, § 30171Printed as Section 6591.5
- Rev. & Tax. Code, § 30179Printed as Section 6591.5
- Rev. & Tax. Code, § 30185Printed as Section 6591.5
- Rev. & Tax. Code, § 30190Printed as Section 6591.5
- Rev. & Tax. Code, § 30202Printed as Section 6591.5
- Rev. & Tax. Code, § 30223Printed as Section 6591.5
- Rev. & Tax. Code, § 30281Printed as Section 6591.5
- Rev. & Tax. Code, § 30281.5Printed as Section 6591.5
- Rev. & Tax. Code, § 30366Printed as Section 6591.5
- Rev. & Tax. Code, § 30406Printed as Section 6591.5
- Rev. & Tax. Code, § 30483Printed as Section 6591.5
Every provision that cites Rev. & Tax. Code, § 6591.5 (132) →
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