Boss Energy Plunges 22% After Withdrawing Honeymoon Feasibility Study.

Boss Energy Wipes Out 22% as Feasibility Reset Shakes Market Confidence.

Boss Energy (ASX: BOE) saw its share price fall sharply today, down 22%, following the release of a new Honeymoon review and the formal withdrawal of its 2021 Enhanced Feasibility Study. Management concluded that the assumptions underpinning that study were materially incorrect from FY27 onward, which is a significant reset for the market.

In practical terms, this means prior expectations around mine life, production profiles, cost curves beyond FY26, and the valuation frameworks relied on by institutions are no longer valid.
The result was a rapid loss of confidence in the company’s long term roadmap, as investors were forced to reassess the visibility of future cash flows.

While this move improves transparency and avoids building expectations on flawed assumptions, it also removes a key anchor for long term valuation, which explains the severity of the market reaction.

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What went wrong with Boss Energy 2021 PFS study

The 2021 study was undermined by several structural issues that became clearer with recent work. First, updated drilling shows higher grade uranium is more pod like and less continuous than originally assumed. This reduces production efficiency and lifts sustaining capital intensity. Mineralisation also does not overlap as expected. Rather than stacking vertically, the horizons sit apart, which limits the ability to reuse infrastructure and pushes capital per pound higher. As a result, the cost profile is less attractive than previously modelled.

Second, downstream processing assumptions proved overly optimistic. Portions of the uranium sit within or adjacent to impermeable lithologies such as clay, which slows leaching or prevents extraction altogether.

This adds complexity and uncertainty to mine planning. Taken together, these issues mean the Honeymoon domain is now expected to produce around 1.5 to 2.5 million pounds less uranium than outlined in the 2021 study. From FY27 onward, this shortens mine life and reduces the revenue outlook relative to earlier expectations.

What Investors need to keep an eye on with Boss Energy

For investors, this is not a quarterly one off issue but a material event that changes how the business is assessed. Institutions are likely to view this as an increase in model risk and forecast uncertainty, which helps explain the sharp re rating we saw in the share price today. Boss has outlined a potential pathway forward, but it remains conceptual rather than proven. The proposed fix centres on a wider spaced ISR well field design, increasing the distance between injection and extraction wells and extending lixiviant residence time, which management believes could lift recoverable uranium by up to 49% and bring additional pounds into the mine plan.

That said, the market will require evidence. Boss has flagged a scoping study in Q2 FY26, followed by a new feasibility study in Q3 FY26. In our view, future shareholder value will be closely tied to the credibility and outcomes of these two milestones, as they will determine whether confidence in the long term production and cost outlook can be rebuilt.