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Superfund Excise Taxes Explained: A Complete Guide
Aug 07 ,2025

Superfund Excise Taxes Explained: A Complete Guide

What is the Superfund Excise Tax?

The Superfund Excise Tax was originally enacted under the Internal Revenue Code Section 4671 and Section 4672. It is meant to help fund the cleanup of hazardous waste sites under the Environmental Protection Agency's (EPA) Superfund program. The tax affects businesses that manufacture, produce, or import certain chemicals and substances that are identified by the IRS. For businesses involved in these activities, understanding the specific tax rates and compliance requirements is crucial.

According to the IRS, taxable substances include various chemicals and materials listed under IRC Section 4672. These substances are subject to a tax rate determined by the Secretary of the Treasury, and taxpayers are required to report and pay the tax using Form 720 and Form 6627.


Who Pays the Superfund Excise Tax?

The Superfund Excise Tax is typically paid by manufacturers, producers, and importers who either sell or use taxable chemicals and substances. This includes businesses that are involved in the manufacturing, production, or importation of certain taxable goods. Importers are also required to pay the tax on substances that they bring into the U.S.

The proposed regulations affect not only those who directly manufacture or produce taxable chemicals but also those who import taxable substances. Importers are allowed to rely on the proposed regulations before the final rules are published, as long as they consistently apply them in the manner outlined by the IRS.


Superfund Excise Tax and Form 720: How Are They Related?

Form 720, the Quarterly Federal Excise Tax Return, is used to report the Superfund Excise Tax along with other federal excise taxes. While there is no separate category for Superfund Excise Tax in Form 720, it is included under the environmental tax categories. The key categories in Form 720 related to Superfund Excise Tax include:

IRS Number 16: Imported Petroleum Products Superfund Tax
This tax applies to petroleum products that are imported into the United States. It helps fund the cleanup of hazardous waste sites associated with petroleum products.

IRS Number 53: Domestic Petroleum Superfund Tax
This tax is imposed on domestically produced petroleum products. It applies to manufacturers, producers, and importers of petroleum used in various industries within the U.S.

IRS Number 54: Chemicals (Other Than ODCs)
This category covers chemicals that are not classified as Ozone Depleting Chemicals (ODCs). These chemicals are subject to the Superfund tax to contribute to the cleanup of contaminated sites.

IRS Number 17: Imported Chemical Substances
This tax applies to chemical substances imported into the U.S. that are identified under the Superfund program. Importers of these substances are required to report and pay the tax.

These categories are reported on Form 720, but the tax amount and detailed calculations are recorded on Form 6627, which provides more specific tax rates for these substances.


Which Chemicals and Substances Are Subject to Superfund Excise Tax?

The substances subject to the Superfund Excise Tax are outlined in Internal Revenue Code Section 4672 and are updated periodically. The IRS maintains a list of taxable substances, with certain chemicals and materials added or removed from the list over time. For instance, Notice 2021-66 provides a detailed list of more than 40 substances subject to the tax, which is updated as the Secretary of the Treasury determines which substances should be taxed.

Importers are required to calculate the tax for these substances using the prescribed rates. However, they may also calculate their own rates if the prescribed ones do not apply to the substance in question.


What Is the Tax Rate for Superfund Excise Tax?

The tax rate for Superfund Excise Tax varies depending on the substance in question. As the rates are subject to change and update regularly, businesses must refer to the latest IRS publications, including Form 6627, to determine the applicable rates for each substance. It’s important to check the IRS website regularly for updated rates and tax obligations.


Form 6627 Reference for Tax rate:

How to Pay Superfund Excise Tax

The Superfund Excise Tax is reported using both Form 720 and Form 6627. Businesses must enter the relevant information on both forms to ensure accurate tax reporting. Form 6627 includes the tax rates, helping businesses calculate the tax due, while Form 720 is used to file the tax return. It is crucial that the amounts listed on both forms match to avoid discrepancies.


Methods to Pay Superfund Excise Tax

There are two methods for paying the Superfund Excise Tax:

  1. Manual Filing: Businesses can fill out both Form 6627 and Form 720 and mail them to the IRS.

  2. Online Filing: For a quicker and more secure process, businesses can file their forms through an IRS-authorized online filing portal.

Recommended: Online filing is often the best method, as it offers faster processing times, secure handling, and a more streamlined filing experience.


For comprehensive information on the Superfund Excise Tax and to explore frequently asked questions, you can visit the following official IRS links:


Conclusion

In conclusion, the Superfund Excise Tax plays a critical role in supporting the cleanup of hazardous waste sites across the U.S. Businesses involved in manufacturing, producing, or importing taxable chemicals must be aware of their tax obligations under this program. By accurately reporting and paying the tax using Forms 720 and 6627, businesses can ensure compliance and contribute to environmental protection efforts.