Cash waterfall

A cash waterfall is the contractual and account-based order in which a project company's cash inflows are applied to permitted uses, from operating costs through debt service, reserve funding and finally equity distributions. AFME's project-finance discussion paper describes a cash waterfall mechanism as contractual and mechanical, with defined payment flows through specific accounts: cash flows are first applied to operating and supply costs, then to debt service, then to funding of any Debt Service Reserve Account (DSRA) and any Maintenance Reserve Account (MRA), and then to the distribution account, ensuring direct allocation to debt service and preventing leakage or misuse of cash.

Cash waterfall use on bank project finance desks

In project finance the borrower is typically a special purpose vehicle (SPV) whose revenues are swept into controlled accounts administered under the accounts agreement and security package. Desks underwrite whether the waterfall matches the credit thesis: operating costs and senior debt service sit above junior claims and equity, reserve top-ups protect liquidity, and distribution conditions lock cash when debt service coverage ratio (DSCR) or other tests fail. IFC's limited-recourse practice separates project assets, contracts and cash flows from the sponsor so lenders can rely on controlled project cash as the primary repayment source.

The standalone project-finance annex that once set out basic criteria for these structures under the OECD Arrangement is gone from the current Arrangement text; the underlying discipline now lives in general market practice and documentation standards such as AFME's, not in a dedicated Arrangement annex. The cash waterfall is the documentary expression of that priority regardless of the source: revenues are applied to operating costs and debt service ahead of any distribution to sponsors.

Typical tiers and account controls

A common senior-secured operating waterfall includes:

• receipt of revenues into a proceeds or revenue account
• payment of permitted operating and supply costs
• scheduled senior interest, fees and principal
• top-up of the debt service reserve account and other required reserves
• cash-sweep or mandatory prepayment tiers, where documented
• subordinated debt service, if any
• transfers to a distribution account only if lock-up tests are met

AFME emphasises that collateral and covenants, including account pledges and restrictions on dividends, additional debt and activity, complete the control package around the waterfall. Without enforceable account control, ranking language alone may not stop leakage.

Distinctions and boundary cases

A cash waterfall is not a statutory insolvency ranking, though insolvency law can override contractual priorities. It is also not synonymous with a cash sweep: the waterfall is the full payment hierarchy; a sweep is one tier that prepays principal from surplus. CRE single-asset facilities use analogous lockbox and payment-priority structures, often with simpler reserve stacks. Merchant or partially contracted projects still use waterfalls, but with tighter distribution tests and higher coverage cushions because revenue volatility is greater.