To a US Senator: support expanding the corporate minimum tax

Personalize. Reference your senator’s committee assignments where possible. The Finance Committee is the operative venue for tax legislation; senators on Finance read this kind of letter more carefully than most.

Dear Senator [Last Name],

I’m writing as a constituent in [city/town]. I want to ask you to support proposals to expand the corporate alternative minimum tax (CAMT) that was enacted in the 2022 Inflation Reduction Act.

The CAMT — the 15% minimum tax on book income for corporations earning over $1 billion in average book income — is one of the most structurally significant changes to the federal tax code in a generation. Two years into implementation, it is collecting meaningful revenue from a small number of very large firms whose effective tax rates had been historically far below the statutory rate. It is a structural floor that does not depend on the legislative branch policing every loophole as it appears.

The follow-on agenda is in front of the Senate. Several proposals would expand the CAMT in ways that would compound its effect:

1. Lower the income threshold from $1 billion to $500 million in book income, capturing a meaningfully larger universe of firms.
2. Raise the minimum rate to 18% or 21%, particularly for firms with the largest book-tax gaps.
3. Tighten the definition of book income to capture deferred-tax-asset and credit gaming.
4. Extend the CAMT’s scope to better cover foreign subsidiary income.

I’m asking you to support these expansions and to defend the CAMT against weakening through Treasury guidance, legislative amendments, or repeal in any future reconciliation package.

The political pressure on the CAMT has been substantial and is donor-driven. Constituent voices on this issue tend to be much quieter. I’m asking you to consider the structural case — that a 15% effective floor for the largest corporations is a basic accountability measure — and to weigh it against the industry pressure to weaken or roll back the program.

I’d appreciate knowing your position on CAMT expansion proposals and on any legislative vehicles that might affect the program in the current session.

Thank you for your service.

Sincerely,

[Your name] [Your address] [Your email or phone, optional]