IRS Adds Chemicals to Taxable Substances List

The IRS announced the addition of 39 chemicals to the list of taxable substances subject to the Superfund Chemical Excise Taxes in Notice 2025-51, 2025-41 IRB 448. 

The Superfund Chemical Excise Taxes apply to manufacturers, producers, or importers who sell or use “taxable chemicals” or “taxable substances” that are manufactured or produced in the U.S. or are imported into the United States. The tax is applicable if the chemicals or substances are considered taxable under §4661 or §4672 of the Internal Revenue Code (“Code”). Businesses must analyze the chemical composition of all of their products and determine where along the supply chain any taxable chemicals or substances are imported into or produced in the U.S. and by whom.

The following substances were added to the List according to the Notice:

1.          Acrylonitrile-butadiene rubber

2.          Bromo-isobutene-isoprene rubber

3.          Chloroprene rubber

4.          Ethylene-propylene-ethylidene nor-bornene rubber

5.          Ethylene vinyl acetate

6.          Ethylene vinyl acetate

7.          Hydrogenated acrylonitrile-butadiene rubber

8.          Isobutene-isoprene rubber

9.          Poly(ethylene-propylene) rubber

10.        Emulsion styrene-butadiene rubber

11.        Solution styrene-butadiene rubber

12.        Emulsion styrene butadiene rubber

13.        Solution styrene-butadiene rubber

14.        Hydrogenated acrylonitrile-butadiene rubber

15.        Bromobutyl isobutylene isoprene rubber

16.        Chlorobutyl isobutylene isoprene rubber

17.        DIPE–di-isopropyl ether

18.        Di-isodecyl phthalate

19.        Di-isononyl adipate

20.        Di-isononyl phthalate

21.        Di-tridecyl phthalate

22.        Ethylene propylene diene (EPDM) rubber   

23.        Isodecyl alcohol

24.        Isodecyl benzoate

25.        Isooctyl alcohol

26.        Linear nonyl phthalate

27.        Linear nonyl undecyl phthalate

28.        Linear undecyl phthalate

29.        Linear nonyl tri-mellitate

30.        Neo decanoic acid

31.        Neo pentanoic acid

32.        Nonene

33.        Regular butyl rubber

34.        Tridecyl alcohol

35.        Tri-isononyl tri-mellitate

36.        Di-isobutylene

37.        Polyisobutylene

38.        Styrene-acrylonitrile

39.        Acrylonitrile butadiene styrene

The effective date for purposes of the excise tax under §4671 of the Code for the taxable substances added to the list is January 1, 2026.

For the effective date for purposes of refund claims under Section 4662(e) of the Internal Revenue Code for the taxable substances added to the list, see the determination for each substance.

The updated list and prescribed tax rates for taxable substances will be included in the instructions to IRS Form 6627, Environmental Taxes.

In November 2021, President Biden signed into law the Infrastructure Investment and Jobs Act, which revived and expanded long dormant excise taxes (known as the Superfund Chemicals Taxes) used to address hazardous waste sites in the United States. The new taxes, which went into effect on July 1, 2022, apply to the sale of certain chemical substances, and to an importer’s sale or use of specified substances.

For more information, contact Liskow attorneys Caroline Lafourcade, Greg Johnson, or Clare Bienvenu.