A gap in federal inflation  data  caused by the 2025 government shutdown has raised questions about how the IRS will set 2027 tax figures, but tax professionals and analysts told Checkpoint the missing month should matter little for most taxpayers.

Each year, the IRS adjusts dozens of tax parameters, including bracket thresholds, the standard deduction, and a range of credits and phaseouts, to keep pace with inflation. Under IRC § 1(f), those adjustments are generally tied to the average chained Consumer Price Index for All Urban Consumers, or C-CPI-U, for the 12-month period ending August 31.

The agency would ordinarily have a full 12-month series of inflation numbers, but the shutdown left the Bureau of Labor Statistics (BLS) unable to publish October 2025 data. BLS stated data it could not collect during the lapse in appropriations cannot be recovered after the fact, so affected figures are permanently suppressed from publication.

Checkpoint has published 2027 projections using the 11 available months. The IRS did not respond to Checkpoint’s request for comment on how it will calculate the adjustments.

To dig deeper, visit the original article on the Thomson Reuters blog.