The Bankable Feasibility Study: What Lenders and Investors Require

What separates a technically credible mining or energy project from a bankable one – and why do so many sponsors discover the answer only when they are already sitting across the table from a lender’s independent engineer?

The pattern we see again and again across capital-intensive project finance mandates is that sponsors arrive with a confident pitch and a project that genuinely has merit – then the independent engineer starts asking questions the document cannot answer, and the deal stalls. Not because the geology is wrong. Not because the commodity price is unfavourable. Because the documentation presented to lenders is not actually bankable. That gap – between what an engineer accepts as technically sound and what a capital provider accepts as commercially bankable – is the single most expensive misunderstanding in project finance.

It is important to remember that a bankable feasibility study is not simply a more detailed version of a scoping study or a pre-feasibility study. It is a categorically different document. It must support a final investment decision, satisfy an independent technical review, survive lender due diligence, and in many cases meet the disclosure requirements of a securities regulator. The level of engineering, cost estimation, and financial modelling required is different in kind, not just in degree.

This piece works through what lenders and equity investors actually require from a bankable feasibility study – the components, the standards, the financial model architecture, and the failure points that derail otherwise sound projects.

What Makes a Feasibility Study Bankable – and Why the Distinction Matters

A technical feasibility study satisfies engineers. A bankable feasibility study satisfies capital providers. The distinction sounds obvious. In practice, it is routinely ignored.

A technical study asks: can this project be built and operated? A bankable feasibility study asks a harder and more consequential question: can this project service its debt, generate an acceptable return on equity, and withstand a sustained downturn in its key variables? Lenders are not reading the study to confirm engineering competence. They are reading it to determine whether the asset can repay them under conditions that are worse than the base case. Put simply, the lender’s credit committee is not looking for reasons to invest – it is looking for reasons the project might not repay them.

A BFS is not a document that gets produced and then handed to the finance team. The financial model, the cost estimates, the resource statement, and the risk register are all interdependent. Pull one thread and the others move. That integration is precisely why sponsors who produce the technical study first and the financial model afterward find themselves in trouble – the model surfaces assumptions the study cannot defend, and by then the cost of remediation is significant. Engaging experienced capital raising consultants early in the process – before the technical study is finalised – is one of the most effective ways to prevent that misalignment.

The typical BFS must deliver enough certainty that a lender will commit capital against it. That means an independently verified resource and reserve estimate, a capital cost estimate within a defined accuracy band, an operating cost model grounded in real-world inputs, and a financial model that produces the coverage ratios a lender’s credit committee requires. In each case, these components carry their own standard, their own methodology, and their own set of questions a lender will raise.

The Core Components: A Lender’s Checklist

Sponsors who understand what lenders are actually looking for inside a BFS can structure the document to answer those questions before they are asked. Missing any one of the following components will stall due diligence:

• Geology and resource estimation – A mineral resource and ore reserve statement compliant with a recognised reporting standard (JORC 2012, NI 43-101, or SAMREC depending on the jurisdiction and capital market). The resource must be classified at Measured and Indicated confidence for the portions underpinning the mine plan.
• Mining or extraction plan – A detailed mine schedule, extraction sequence, and production rate supported by geotechnical and hydrogeological studies. Lenders want to see the plan stress-tested against grade variability.
• Processing and metallurgy – Testwork results at sufficient scale to confirm recovery rates, reagent consumptions, and product specifications. For project finance purposes, metallurgical testwork must be at pilot or demonstration scale, not bench scale.
• Infrastructure – Water supply, power, tailings management, site access, and logistics. Each element must carry a cost estimate and a development plan.
• Environmental and social impact assessment – A credible ESIA aligned with IFC Performance Standards, including a stakeholder engagement record and a draft environmental and social management plan. This is not a regulatory checkbox; it is a credit consideration for any lender applying the Equator Principles.
• Capital cost estimate – At Class 3 accuracy or better under the AACE International classification system (typically minus 10 to plus 15 percent). A scoping-level estimate submitted in place of a bankable-level estimate will be identified immediately.
• Operating cost model – Unit costs built from first principles, not benchmarked from analogous operations without adjustment. Lenders want to see cost assumptions tied directly to the mine plan and the metallurgical recovery rates.
• Financial model – The document that converts all technical assumptions into returns, debt service coverage, IRR, and NPV. More on this below.
• Risk register – A systematic identification of technical, commercial, regulatory, and sovereign risk exposures, with mitigation strategies attached to each. The risk register should inform the sensitivity analysis in the financial model.

Capital Cost Estimates: What Accuracy Class Lenders Actually Require

The AACE International classification system provides a shared language for capital cost estimate accuracy that lenders and sponsors can use to calibrate expectations. The five classes run from Class 5 (conceptual, minus 20 to plus 50 percent accuracy) to Class 1 (definitive, minus 3 to plus 10 percent accuracy). In practice:

A bankable feasibility study submitted with a Class 4 or Class 5 estimate will be recognised as such by any competent independent engineer. Lenders will either decline to proceed or require a costly estimate upgrade before debt sizing can begin. Sponsors who try to save money at the cost estimation stage almost always spend more correcting the problem under time pressure later – and by then the time pressure is real.

What lenders are particularly sensitive to are contingency assumptions. In lender due diligence, a contingency allowance that is visibly thin relative to the project’s greenfield exposure and jurisdictional complexity is treated as a credibility problem, not a rounding issue. A credible contingency for a remote greenfield project must be grounded in a methodology the BFS can defend, and lenders have seen enough cost overruns to know that optimism at the BFS stage is simply a problem deferred to construction.

Pre-Feasibility Versus Bankable Feasibility: When to Move and What It Costs

Sponsors frequently try to raise project finance on a pre-feasibility study to save money. Some equity investors will engage on a PFS basis for early-stage positioning. Project finance lenders, as a general rule, will not size debt against a PFS.

The practical difference between a PFS and a BFS extends beyond cost estimate accuracy. A PFS can carry a higher proportion of Inferred resources in the mine plan; a BFS cannot. A BFS requires deeper metallurgical testwork, more advanced environmental permitting, and typically 10 to 15 percent basic engineering versus conceptual layouts for a PFS.

The move from PFS to BFS is expensive. Depending on project scale and commodity, the additional technical work can represent a material investment that is not recoverable if the project fails at a later stage. Sponsors and their capital raising advisors must make a clear-eyed assessment of whether a project has sufficient merit to justify the BFS spend before committing. Healthy financial discipline at this decision point matters more than most sponsors acknowledge.

The trigger for upgrading a PFS to a BFS is typically one of three things:

• A lender or off-taker requires it as a condition of engagement
• The board has made a provisional final investment decision pending BFS completion
• Institutional investors require it for due diligence in a capital raise

In each case, the decision to proceed should be supported by a model that already demonstrates the economics at a level of confidence that justifies the spend.

Resource Reporting Standards: JORC, NI 43-101, and the Cross-Border Problem

For listed companies and institutional lenders, the BFS mineral resource and reserve statement must be authored or signed off by an independent qualified person under a recognised reporting standard. JORC 2012 is the operative standard for Australian and many Asia-Pacific listed companies. NI 43-101 governs disclosure for TSX and TSX-V listed entities and is widely recognised by North American institutional lenders.

For cross-border capital stacks, the reality is more complicated than jurisdiction-specific requirements. A copper project in Latin America seeking ASX-listed equity and US institutional debt simultaneously may need JORC compliance for Australian shareholders and NI 43-101 cross-disclosure for North American investors. The two standards are broadly compatible but not identical. A BFS that ticks all the boxes under one standard may require supplemental disclosure under the other.

Sponsors building a cross-border capital stack should resolve this early, ideally before the BFS resource estimate is finalised. Retrofitting a JORC-compliant resource statement to satisfy NI 43-101 requirements – or vice versa – is a costly and time-consuming exercise that can delay a roadshow by months. It is the kind of structural problem that looks small on paper and becomes large very quickly under investor scrutiny.

Environmental and Social: A Credit Risk, Not a Compliance Exercise

Project finance lenders applying the Equator Principles – now in their fourth iteration (EP4) – treat environmental and social risk as a credit risk. This is not widely understood by first-time sponsors.

Under EP4, a project is categorised as Category A (significant adverse impacts), Category B (limited adverse impacts), or Category C (minimal impacts) based on the environmental and social review. Category A and B projects require an Environmental and Social Impact Assessment aligned with IFC Performance Standards, a Stakeholder Engagement Plan, and an Environmental and Social Management Plan with monitoring commitments. The BFS environmental section is evaluated against these requirements by the lender’s own environmental and social consultant.

A BFS that presents the environmental permitting status as a list of approvals obtained and pending – without demonstrating a credible ESMP and a genuine stakeholder engagement process – will fail lender environmental and social due diligence regardless of the technical and financial quality of the rest of the document. In our experience advising sponsors on capital-intensive projects, remediating an ESIA that was structured to meet local permitting requirements rather than IFC Performance Standards is among the most time-consuming and confidence-eroding problems a project can face at the lender engagement stage. It is clear that long-term strategic investors are paying closer attention to this dimension than they were even five years ago, and the trend is not reversing.

The Financial Model: The Single Point of Truth

The financial model inside a BFS is not a spreadsheet appended after the technical work is done. It is the document that converts every assumption in the BFS – the mine plan, the capital cost estimate, the operating cost model, the commodity price forecast, the financing structure – into the outputs a lender’s credit committee requires: debt service coverage ratio (DSCR), loan life coverage ratio (LLCR), project life coverage ratio (PLCR), IRR, and NPV.

The model-first discipline matters enormously here. At Projects RH, we provide capital raising consulting that embeds the financial model into the BFS as it is assembled – not after – so that every capital cost and operating cost assumption is immediately stress-tested against debt service coverage and return thresholds before the technical document is finalised. That approach catches problems early – and it is far cheaper to revise a mine plan or a metallurgical assumption at the BFS drafting stage than to discover during lender due diligence that the project cannot service its debt at the assumed commodity price.

A positive NPV in the BFS financial model does not mean the project is bankable. Lenders evaluate DSCR at a downside commodity price scenario, not NPV at base case. A project can show a compelling NPV and still be unbankable if the debt service coverage ratio falls below the minimum threshold a lender’s credit committee requires – a DSCR of 1.0x means cash flow exactly equals debt service, which provides no buffer at all – in a commodity price downside scenario. The sensitivity table is the single most read page in the BFS by a lender’s credit committee. Sponsors should build it to answer the credit committee’s questions proactively, not as an afterthought to the base case.

How Lenders and Equity Investors Read the BFS Differently

A project finance lender and an equity investor are reading the same document, but they are looking for fundamentally different things.

The lender is asking: what is the worst reasonable outcome, and does the project still service its debt in that scenario? The lender’s independent engineer will interrogate the capital cost estimate, the production assumptions, and the financial model inputs with a sceptical eye. The lender’s lawyer will review the offtake agreement, the construction contract structure, and the permitting status. The lender’s environmental consultant will evaluate the ESIA. The lender is not trying to find reasons to invest; they are trying to find reasons the project might not repay them.

The equity investor is asking something different: what is the upside, and does the management team have the competence and the relationships to capture it? Equity investors read the BFS for confirmation that the technical risk is real but manageable, that the resource is large enough to justify the capital cost, and that the team behind the project has navigated enough of the value chain to be credible. For long-term strategic investors, the management section of the BFS is as important as the resource estimate.

What is equally important to understand is that the BFS must be structured to satisfy both audiences simultaneously. The technical and financial rigour satisfies the lender. The clarity of the strategic narrative and the quality of the management discussion satisfies the equity investor. A BFS that is technically rigorous but strategically opaque will close debt and fail to close equity. A BFS that tells a compelling story but cannot withstand the independent engineer’s review will close neither. Capital and structure must align – and the BFS is where that alignment is either built or revealed to be absent. Firms that specialise in project finance advisors understand both audiences and can help structure the document to speak to each of them without sacrificing rigour for narrative or vice versa.

How the BFS Drives the Information Memorandum

The Information Memorandum for a capital raise is not a separate document from the BFS. It is a structured defence of the BFS assumptions under investor scrutiny. The capital cost section of the IM maps directly to the BFS cost estimate. The financial section of the IM is the model derived from BFS inputs. The risk section of the IM draws from the BFS risk register. When sponsors produce the BFS and the IM as separate workstreams – often with different advisors working in parallel – the two documents frequently contradict each other on figures, assumptions, and narrative framing.

A lender’s independent engineer who identifies a discrepancy between the IM and the BFS will raise it as a due diligence finding. The sponsor then manages an investor relations problem and a technical remediation problem simultaneously. This situation is entirely avoidable if the IM is built from the BFS from the outset, with the financial model as the single point of truth connecting both documents. The spruikers who promise a compelling IM without first interrogating the underlying model are, in the end, setting their clients up for a harder conversation later.

Common Reasons a BFS Fails Lender Scrutiny

The patterns repeat. In each case, the failure is structural rather than technical:

• Capital cost estimate submitted at Class 4 or Class 5 accuracy when a Class 3 or better is required for debt sizing
• Resource and reserve statement authored by the sponsor’s internal team without independent qualified person sign-off
• Financial model built as a static exhibit rather than an auditable, updateable document that can accommodate lender sensitivity runs
• ESIA structured to meet local permitting requirements rather than IFC Performance Standards, failing Equator Principles review
• Sensitivity analysis limited to commodity price, ignoring capital cost overrun and production shortfall scenarios that lenders routinely stress
• Offtake agreement (or lack thereof) not addressed in the financial model – a project without a bankable offtake or PPA (power purchase agreement) often cannot support project finance debt regardless of the technical quality of the rest of the BFS
• Sovereign risk not explicitly modelled or mitigated in projects located in jurisdictions where political risk insurance or development finance institution support would be expected by commercial lenders

Frequently Asked Questions

What is the difference between a bankable feasibility study and a pre-feasibility study?

A pre-feasibility study establishes whether a project is worth advancing to full feasibility work. It carries a lower capital cost estimate accuracy (typically Class 4, minus 15 to plus 30 percent) and may include Inferred resources in the mine plan. A bankable feasibility study must support a final investment decision and satisfy lender due diligence. It requires Class 3 or better cost estimate accuracy, Measured and Indicated resource classification for the mineable inventory, pilot-scale metallurgical testwork, and an independently reviewed financial model capable of producing the coverage ratios a project finance lender requires. The two are different in kind, not just in detail.

Can a sponsor use its own team to produce a bankable feasibility study?

Internal teams can contribute substantially to BFS preparation and often do. However, for institutional capital raises – whether project finance debt or listed equity – the resource and reserve statement must be signed off by an independent qualified person under JORC, NI 43-101, or SAMREC as applicable. The capital cost estimate and the financial model will also be reviewed by the lender’s independent engineer. A BFS authored entirely in-house without external independent review will not satisfy institutional due diligence standards, and lenders will require remediation before proceeding. An independent assessment is not a formality; it is what gives the document its credibility with capital providers.

What financial model outputs do lenders require from a BFS?

Project finance lenders size and test debt using three coverage ratios: debt service coverage ratio (DSCR – cash available in a period divided by debt service due in that period), loan life coverage ratio (LLCR – NPV of cash flows over the loan life divided by outstanding debt), and project life coverage ratio (PLCR – NPV of cash flows over the full project life divided by outstanding debt). The BFS financial model must produce all three ratios under the base case and at least two downside scenarios – typically a commodity price downside and a capital cost overrun scenario. A model that only produces IRR and NPV has not been built to satisfy a project finance credit committee.

How long does it take to produce a bankable feasibility study?

For a mid-size mining or energy project, the BFS process typically runs 18 to 36 months from the completion of a pre-feasibility study. The timeline is driven primarily by the permitting process, the metallurgical testwork program, and the engineering design program. Sponsors who try to compress this timeline to accelerate a capital raise almost always create problems that extend the overall time to financial close by more than the time they saved. Resilience at the preparation stage – the discipline to do the work properly rather than quickly – is what separates projects that close from projects that stall.

Does every project need a bankable feasibility study to raise capital?

Not always. Growth equity investors and some development finance institutions will engage on a PFS basis for early-stage equity positioning. Royalty and streaming finance structures have been used to fund projects at PFS stage. However, for traditional project finance debt from commercial lenders and most Equator Principles financial institutions, a BFS is a prerequisite for debt sizing. Sponsors should align their documentation requirements with their capital stack early – before committing to the cost of BFS preparation. The capital structure conversation and the documentation conversation are not sequential; they need to happen together.

Strong projects fail because capital and structure do not meet at the right time. This is not an abstraction – it is the lived experience of sponsors who arrive at a lender meeting with a document that answers every engineering question and none of the financial ones. The bankable feasibility study, built right, is the bridge between a technically sound project and a commercially funded one. It requires discipline in the cost estimation, rigour in the resource reporting, genuine commitment to the environmental and social process, and – above all – a financial model that is built to be interrogated, not admired.

The deals worth doing rarely fail on the fundamentals. They fail on the preparation.