The US Senate is now engaged in the process to craft and pass a budget reconciliation bill, with some committees releasing draft text to meet their instructions — although not yet for tax. A Finance Committee member indicated that Republican senators could present President Trump a draft of tax revisions to the House bill as early as this weekend, although the process could extend into next week.

Senate Majority Leader John Thune (R-SD) remains committed to adhering to the Administration's goal for completing and sending the President a reconciliation bill by 4 July. Under this timeline, a Senate vote would take place the last week of June; some Senate Republicans believe that deadline may slip. The Majority Leader was quoted as saying the Finance Committee portion of the bill will likely be released the week of 9 June, with some committees planning a markup and others following suit at the discretion of their chairmen.

Senators reportedly are in discussions with House members regarding various provisions in the House-passed bill, including proposed new IRC Section 899, which targets so-called "unfair foreign taxes" and would increase applicable tax rates and expand base erosion and anti-abuse tax (BEAT) rules in certain circumstances. The "unfair foreign taxes" include the undertaxed profits rule (UTPR) and digital services taxes. According to the House Budget Committee Report that accompanied the bill, the provision is not intended to turn off the portfolio interest exemption, but concerns persist over potential effects on foreign investment in the US.

Addressing possible changes to the House legislation, the Majority Leader said, "It'll have to track fairly closely, obviously, with the House bill because they've got a fragile majority and struck a very delicate balance in getting it passed in the House in the first place," Senators nevertheless will want to make some changes or additions to the House bill, the Leader said. The Congressional Budget Office this week estimated the proposed House reconciliation bill would increase the deficit by $2.4t over 10 years and require $550b in interest payments.

Certain groups of Republican senators have expressed reservations about the House bill's reductions to Inflation Reduction Act (IRA) energy tax credits and Medicare changes and there is also wariness over the bill's overall spending level and insufficient deficit reduction, plus the pending debt limit increase.

The Senate Finance Committee on 3 June approved, along party lines, the nomination of former Rep. Billy Long (R-MO) to be IRS Commissioner. The nomination next will go to the full Senate for consideration.

President Trump on 3 June 2025 issued a proclamation titled "Adjusting Imports of Aluminum and Steel into the United States." Effective 4 June, the US has increased tariffs on aluminum and steel imports from 25% to 50% ad valorem. The new tariff rates apply to both steel and aluminum articles, as well as to their derivative products.

The principle of non-stacking remains in effect, meaning that articles already subject to other tariffs will not incur additional tariffs from these new adjustments, except for imports from the United Kingdom, which will maintain a 25% tariff rate. A Global Trade Alert has details.

Treasury Deputy Secretary Michael Faulkender said on 3 June that the United States will take action if the OECD doesn't accept several existing US tax provisions as being compliant with the global minimum tax initiative. Faulkender referred to certain US tax provisions, such as the global intangible low-taxed income (GILTI) tax rates, the foreign derived intangible income (FDII) and BEAT. According to press reports, the official said: "The notion that those are not going to be deemed compliant just is a nonstarter for us," and that the US is not "ceding our sovereignty … to the OECD."

The OECD on 2 June released the Consolidated text of the Common Reporting Standard (CRS) for the automatic exchange of financial account information in tax matters. Recall that the CRS earlier was expanded to include digital financial products as well as indirect investments (e.g., derivatives) in cryptocurrency. The OECD on the same day also released the CRS Status Message XML Schema and the Crypto-Asset Reporting Framework Status Message XML Schema.