An international grant is agreed in one currency and spent in another, and the gap between those two facts is where reporting goes wrong.
The first question to settle is which date sets the rate. There are three candidates and they give different answers: the date of the award decision, the date the funds are paid, and the date the grantee reports. A grant approved at one rate, paid three months later at another and reported at a third produces three defensible figures for the same grant, and a finance team that cannot reconcile them.
Pick one, state it in the grant agreement, and apply the same one across the portfolio. The choice matters less than the consistency.
Then decide who carries the risk. The Council on Foundations documents the standard approaches to currency fluctuation in international grantmaking: paying the full amount in advance, holding it in escrow at the rate agreed at negotiation, or hedging the exposure over the life of the grant. Each puts the risk in a different place. What is not an option is leaving it undefined, because the grantee absorbs it by default and discovers the shortfall halfway through the project.
Two operational losses are worth naming because they are avoidable.
Double conversion. Funds converted twice on the way to the grantee, usually through an intermediate currency or account, lose margin at each step. Financial guidance published for UK Aid Match grant holders flags this as a recurring and unnecessary cost.
Poor rates from the wrong institution. The same guidance notes grantees receiving materially worse rates by converting through local banks rather than international ones. A funder can help simply by raising it before the first payment.
For reporting, hold both figures. The amount in the grantee's currency is what they actually spent and what their own accounts show. The amount in yours is what the programme cost you. Storing only the converted figure means you can never answer a question about the project itself.
A grant management software platform records the award, the payment and the report in their own currencies, each with its rate and date attached, so a portfolio total and a single grant's local reality stay reconcilable. That is also what keeps grantee reporting comparable when partners report in five currencies.