A bankable feasibility study is the most detailed pre-construction evaluation a project undergoes, and its purpose is narrow and specific: to prove to lenders that the project will generate enough cash to repay its debt on the strength of its own economics. Because most large mining, energy, and infrastructure projects are financed on a non-recourse or limited-recourse basis, the lender’s protection is the project itself. This document is what converts a proposition from speculative to fundable, and it has to hold up under independent technical, financial, environmental, and legal scrutiny before a bank will commit.
How It Differs From Earlier Studies
Projects reach a bankable feasibility study through progressively more detailed stages. A scoping or conceptual study offers a first look at whether an idea has enough promise to justify further work, and its cost estimates can swing 30 percent or more in either direction. A pre-feasibility study tightens the picture by using measured and indicated resources rather than inferred ones, evaluating development alternatives with more detailed engineering, and benchmarking costs against recent comparable projects. Strong mining economics can occasionally support a production decision at the pre-feasibility stage when the project is financed entirely with equity.
Once bank debt enters the picture, that ceiling almost always rises. The bankable feasibility study, also called a definitive feasibility study, uses only mineral reserves, involves definitive engineering designs, and bases costs on actual bids and supplier quotes rather than parametric estimates. It is essential for larger, more capital-intensive projects where economics are tighter and the stakes for lenders are higher.
The Technical Foundation
The technical work defines exactly what the project will extract, build, and operate. For mining projects, this starts with the resource model, which classifies the deposit by the level of geological confidence behind the estimates. An inferred resource is supported by limited evidence that suggests continuity without confirming it. An indicated resource has more reliable sampling and allows reasonable assumptions about geological and grade continuity. A measured resource sits at the top, with detailed exploration confirming continuity at high confidence.1Canadian Institute of Mining, Metallurgy and Petroleum. CIM Definition Standards for Mineral Resources and Mineral Reserves
Only measured and indicated resources can be converted into mineral reserves, proven and probable respectively, and a bankable study relies on reserves for its economic projections. Resources that haven’t been upgraded to reserves don’t drive the cash flow model.
The engineering package must reach Front-End Engineering Design detail: specific site layouts, process flow diagrams, metallurgical test results confirming how ore will be processed, water and power supply plans, and a construction schedule with identifiable milestones. Designs need to be far enough along that a contractor could price them with confidence. Vague or conceptual drawings are a red flag because they introduce cost uncertainty that the financial model cannot absorb.
Cost Estimates and the Financial Model
Cost estimate accuracy is one of the clearest markers separating a bankable study from earlier work. The AACE International classification system provides the industry benchmark, and a bankable study typically targets a Class 2 estimate. That level expects accuracy of roughly negative 5 to 15 percent on the low side and positive 5 to 20 percent on the high, built from detailed unit costs and supplier quotes rather than scaling from similar projects.2AACE International. 18R-97 Cost Estimate Classification System Capital cost estimates at this stage generally carry an accuracy of plus or minus 10 to 15 percent, with a contingency of around 10 percent standard for a definitive-level study.
Operating cost projections require similar granularity. Labor, consumables, energy, maintenance, and replacement schedules are broken down by year across the full project life. Lenders don’t accept flat annual estimates. They want to see costs ramp during commissioning, stabilize during steady-state operations, and shift again during wind-down. Each line item should trace back to a verifiable assumption: a power purchase agreement, a labor market survey, a reagent supply contract.
Building the Model
The financial model layers capital and operating costs with revenue projections to produce the cash flow forecasts lenders use to size the loan. Revenue assumptions need careful handling. Analysts examine historical price trends and supply-demand dynamics for the project’s output, but the bankable price deck usually sits below spot prices to build in a margin of safety. Jurisdiction-specific tax obligations, royalties, and depreciation schedules feed into the model as well.
Energy projects in the United States also have to account for federal tax incentives. Under the Inflation Reduction Act, tax credits can cover 30 to 70 percent of the cost of renewable energy projects, and the method of monetizing them shapes the entire financing structure. Section 6418 of the Internal Revenue Code allows direct transfer of tax credits to unrelated buyers, which is simpler and cheaper than the partnership flip structures that dominated before 2022.3U.S. Department of the Treasury. U.S. Department of the Treasury, IRS Release Final Rules on Provision to Expand Reach of Clean Energy Tax Credits The study needs to document which credits the project qualifies for, how they will be monetized, and its pre-file registration status through the IRS Energy Credits Online system.
Sensitivity and Coverage Ratios
Lenders don’t take the base case at face value. Sensitivity analysis isolates individual variables and shows how the economics move when each one deteriorates. Commodity or energy prices, operating costs, production volumes, exchange rates, and interest rates are the standard variables tested. A well-built model shows exactly how much each can worsen before the project can no longer service its debt.
The primary metric is the Debt Service Coverage Ratio, which divides cash available for debt service in a given period by the actual debt payment due. Most project finance lenders require a minimum well above 1.0x, with the threshold depending on sector and risk profile. Infrastructure and mining projects with commodity price exposure typically face higher minimums than contracted-revenue projects like toll roads or power plants with long-term offtake. The Loan Life Coverage Ratio adds a complementary view by comparing the present value of all future cash flows over the loan’s remaining term to the outstanding debt balance. Both ratios must hold up in the base case and across the downside scenarios sensitivity analysis generates.
Environmental and Social Risk
No lender will finance a project carrying unquantified environmental or social liability. The study must document baseline conditions at the site, identify every material impact from construction and operations, and set out specific mitigation strategies with costs built into the financial model.
The Equator Principles provide the framework most major international lenders follow, and they apply to project finance transactions with total capital cost of $10 million or more.4Equator Principles. The Equator Principles EP4 Projects fall into Category A (potentially significant, diverse, irreversible, or unprecedented impacts), Category B (limited, site-specific, largely reversible), or Category C (minimal or no adverse risk). The category determines how much environmental and social assessment work the study must include, with Category A requiring the most extensive documentation and independent review.5Equator Principles. About the Equator Principles
Closure and reclamation plans deserve particular attention because the liability outlives the project itself. Lenders want a detailed plan for restoring the site after operations end and a funded mechanism, such as a reclamation bond or trust, that ensures the money is available even if the sponsor becomes insolvent. Treating closure as an afterthought with round-number cost estimates in an appendix signals that the sponsor hasn’t thought carefully about long-term risk.
Reporting Standards and the Qualified Person
The technical findings must comply with recognized reporting standards, and three regimes cover most of the global market. In the United States, publicly listed mining companies follow Subpart 1300 of Regulation S-K, which specifies how mineral resources and reserves must be classified and reported using defined categories tied to geological confidence.6eCFR. 17 CFR Part 229 Subpart 229.1300 – Disclosure by Registrants Engaged in Mining Operations In Canada, National Instrument 43-101 governs mineral project disclosures and recognizes the JORC Code from Australia and the PERC Code from Europe as acceptable foreign equivalents.7Ontario Securities Commission. National Instrument 43-101 Standards of Disclosure for Mineral Projects The JORC Code has been part of ASX listing rules since 1989. Definitions across these frameworks are substantially harmonized, so a bank reviewing a study prepared under one code can reasonably compare it to another.
Every major standard requires the technical report to be certified by a designated expert. The SEC and NI 43-101 use the term “qualified person”; the JORC Code uses “competent person.” The core requirements are strikingly similar: at least five years of relevant experience in the specific type of mineralization and activity being evaluated, and membership in good standing with a recognized professional organization that has authority to impose discipline.6eCFR. 17 CFR Part 229 Subpart 229.1300 – Disclosure by Registrants Engaged in Mining Operations8JORC. Frequently Asked Questions – JORC Code “Relevant” is strict. Deep expertise in disseminated gold deposits would not automatically qualify someone to sign off on a vein-type tin deposit. The study’s credibility is tied directly to the professional reputation of the person who certified it.
Commercial Agreements That Make It Bankable
A strong feasibility study still isn’t bankable without the commercial agreements that transfer construction and market risk away from the project company. Two matter most: the EPC contract and the offtake agreement.
An EPC contract lenders consider bankable typically has a fixed lump-sum price, a fixed completion date, liquidated damages for both delay and underperformance, output and performance guarantees backed by testing protocols, and single-point responsibility resting with the contractor. The goal is to keep the project company, and by extension the lender, from bearing construction risk. Lenders also look for parent company guarantees or performance bonds backing the contractor’s obligations, because strong contract terms mean nothing if the contractor cannot pay when called upon.
Offtake agreements address the revenue side. A long-term contract with a creditworthy buyer for some or all of the project’s output gives lenders confidence that the revenue projections aren’t purely speculative. Strength depends on the buyer’s credit rating, the contract’s duration relative to the loan term, the pricing mechanism (fixed, indexed, or market-based), and the take-or-pay provisions obligating payment even without delivery. Projects with strong offtake coverage often secure better loan terms because the lender is effectively underwriting the buyer’s credit rather than commodity price risk.
Beyond EPC and offtake, lenders typically require evidence of adequate insurance coverage (construction all-risk, business interruption, third-party liability), an operations and maintenance plan whether performed in-house or by a contracted operator, and the permits and licenses necessary to begin construction. A study with strong economics but term-sheet-stage commercial agreements signals that the project isn’t actually ready for financing.
What Happens After Submission
Submitting the completed study is the start of the lender’s review, not the end of the sponsor’s work. The centerpiece is the independent technical assessment, sometimes called the Lender’s Independent Engineer review. The bank appoints an engineering firm with no prior relationship to the project to audit the study’s technical assumptions, cost estimates, resource model, and engineering designs. The firm doesn’t take the numbers on faith. They re-examine the geological data, test whether the process design will actually achieve the recovery rates claimed, benchmark capital costs against comparable projects, and evaluate whether the construction schedule is realistic. This review can take several months depending on complexity and how well organized the data room is.
The independent engineer produces a report for the bank’s credit committee flagging strengths, weaknesses, and residual risks. The credit committee weighs the study, the independent engineer’s findings, legal opinions, and commercial agreements to reach a final decision. If the project clears the bank’s internal risk-return threshold, the result is a commitment letter specifying the loan amount, interest rate, required covenants including ongoing DSCR maintenance, and conditions precedent to disbursement. That commitment letter marks the transition from planning to financial close, and it only happens when every piece of the bankable feasibility study holds up under independent scrutiny.