Highlights

  • Boss Energy has withdrawn the 2021 Enhanced Feasibility Study following the Honeymoon Review findings.
  • A wide-spaced wellfield design is being assessed under a newly initiated feasibility process.
  • FY26 production and cost guidance remains unchanged despite expected FY27 impacts.

Boss Energy Limited (ASX:BOE) has completed its Honeymoon Review, which has identified material and significant deviations from the assumptions underpinning the company’s 2021 Enhanced Feasibility Study (EFS). The review indicates that from FY27 onwards, mine life production and costs could differ from previous expectations due to reduced continuity of higher-grade mineralisation, limited overlap between mineralised zones, lower leachability, and smaller wellfields.

Based on these findings, the company has formally withdrawn the EFS and advised that it should no longer be relied upon for medium- to long-term operational planning or performance assessment.

Alternative Wellfield Design Under Evaluation
As part of the Honeymoon Review, Boss assessed the suitability of the current wellfield design and identified a potential alternative approach involving a wide-spaced wellfield configuration. This concept is at an early stage and is based on the company’s updated understanding of the Honeymoon resource and deposit characteristics.

Boss has initiated a series of accelerated work programs to evaluate the potential economic outcomes associated with this alternative design through a New Feasibility Study. An initial update is expected in Q1CY26, followed by completion of a Scoping Study targeted for Q2CY26. The New Feasibility Study is scheduled for completion in Q3CY26.

The wide-spaced wellfield design is being assessed for its potential to increase leaching duration, reduce reagent consumption, utilise wellfield infrastructure across a larger surface area, and place more uranium under leach compared to the existing design.

Satellite Deposits Added to Growth Assessment
In parallel, Boss has commenced a detailed work program focused on integrating the Gould’s Dam and Jason’s Deposit satellite deposits into the production profile. This work includes updating the resource model and assessing development timelines. Further details related to these deposits are expected to be released during Q1CY26.

The company has indicated that outcomes from the wide-spaced wellfield design assessment could also influence recoverability and cost structures at these satellite deposits.

FY26 Guidance Maintained Amid Ongoing Studies
Boss confirmed that FY26 production and cost guidance remains unchanged, with expected production of 1.6Mlbs of U₃O₈, C1 costs of USD 27–28/lb, and all-in sustaining costs (AISC) of USD 41–45/lb. During Q2FY26, Honeymoon recorded 357klbs of U₃O₈ drummed up to 10 December 2025.

For FY27, based on the existing wellfield design and prior to the outcomes of the New Feasibility Study, production and cost levels are expected to be similar to FY26, although AISC is anticipated to be approximately 15% higher due to an increased share of sustaining capital.

As of 30 September 2025, Boss reported AUD 212 million in cash and liquid assets to fund the ongoing feasibility work programs and potential changes to the wellfield design.

Share Price Snapshot
BOE was trading 27.316% lower at AUD 1.137 per share as of 18 December 2025.