FX leakage: why it persists even when finance knows better

When your business operates internationally, foreign exchange (FX) exposure is inevitable.

Customers pay in local currencies, suppliers invoice in others, and your books need to close in one base currency. At each step, money crosses borders and currencies.

But, FX shouldn’t be a mystery to your team, especially because you understand its risks better than anyone in the business. You model exposure, you understand what conversion spreads cost at scale, and you've sat through enough month-end reviews to know how quickly it adds up.

And yet, FX leakage keeps showing up. 

Not because rates moved dramatically or your strategy was wrong. But because the gap between what you intended and what actually happened was decided inside your payments infrastructure, long before you even saw the numbers.

Where leakage actually starts

Most FX cost conversations focus on the rate itself. What spread you're paying or which provider offers the best conversion pricing. It's a reasonable place to look, but it frames the problem as a procurement decision, and that's where the analysis tends to stop.

Leakage doesn't necessarily only come from bad rates. It comes from unnecessary conversions: money being converted when it didn't need to be, earlier than intended, or more than once before it reaches its destination. 

Here's a common pattern: a merchant accepts payments in EUR, the PSP converts those funds to GBP at settlement, and the merchant converts back to EUR to pay European suppliers. The currency started in EUR, took a detour through GBP, and ended back in EUR, with two sets of conversion costs and no business reason for either. We’ve seen this same pattern with one of our own merchants that accepts in CAD, settles in EUR, and converts back to CAD to pay local tax authorities in Canada. Neither conversion needed to happen.

The principle finance is trying to apply

Natural hedging is the instinct behind most FX strategies for global businesses and the logic is straightforward. If you accept revenue in EUR and pay suppliers in EUR, you don't need to convert. Match the currency of your inflows to the currency of your outflows and the exposure disappears. 

The problem is that natural hedging assumes you control where funds settle and when conversion happens. In practice, most finance teams don't. While the strategy is sound, the infrastructure doesn’t always support it. 

Why execution breaks down

Even when a natural hedge is structurally possible, getting it to work depends on decisions that happen before reaching finance. Those decisions tend to fall into four categories:

• PSP default currencies. Most PSPs convert funds at settlement unless configured otherwise. That default reflects their operational convenience, not your treasury intent. If you're not actively managing this configuration, conversion is happening automatically.
• Forced conversions at checkout. Some providers convert at the point of sale, not at settlement. The customer pays in their local currency and the merchant receives in a different one. The conversion has already happened before the transaction even closes.
• Settlement timing. Even when conversions can be deferred, the window is often determined by provider settlement schedules rather than finance's preference. By the time the funds are visible in your account, the decision has been made for you.
• Account structure. Holding balances in multiple currencies requires multi-currency accounts, which not all providers support, and which you may not have configured deliberately.

The common thread running through all four is that none of these decisions sits within your control. Each one happens at the infrastructure layer, earlier in the payment lifecycle, and by the time the numbers arrive on your desk, the outcome is already fixed. 

What finance actually experiences

None of this leakage surfaces as a configuration problem. It surfaces as something known too well by your finance team: variance.

FX shows up at month-end as a line to explain. Either the rate moved, the provider charged more than expected, or the settlement came through short. Your team investigates, reconciles the difference, and closes the period. Then it happens again next month.

The underlying cause rarely makes it into the discussion. The question becomes “how do we explain this?” rather than “how do we stop it from happening?” And so, it is absorbed as a cost of operating globally.

At lower volumes, it’s manageable. But leakage compounds quickly. To put a number on it, a blended FX spread of 1% on cross-currency transactions is a conservative estimate for a business relying on PSP conversions. At $1 million in cross-border volume, that's $10,000 in unnecessary conversion cost. At $50 million, you're looking at $500,000. Not a line item to explain, but a meaningful margin impact.

From passive variance to active control

The shift that matters isn't finding a better FX rate, but moving conversion from a default to a decision. One that finance makes deliberately, based on treasury intent, rather than one that payment infrastructure makes by default.

That means being able to choose where funds settle, whether balances are held or converted, when conversion happens, and which rails move money next. Without that control, natural hedging stays theoretical. With it, finance can align payment flows with actual operational intent: accept in EUR, hold in EUR, pay out in EUR, and convert only when there's no natural match, at a time and rate you've chosen.

Primer makes that control executable. Rather than pushing merchants toward a single settlement currency or hiding FX decisions inside provider defaults, it surfaces available options per market, gives finance teams visibility into market-linked rates before conversion happens, and lets you configure when and how funds move, all in one place. 

FX is a design decision

The pattern we see consistently with global merchants is that FX leakage is rarely a knowledge problem. Finance teams understand the cost. What they often lack is the infrastructure to act on it and intervene at the moment conversion decisions are being made, rather than after the fact.

When pay-in, settlement, and treasury operate across separate systems, those decisions are fragmented. Different providers make them at different points in the lifecycle, often without visibility into what happens downstream. When money movement is unified, they can be aligned.

FX cost doesn't disappear, but it moves from being something that happens to your business to something your business controls. For finance teams scaling internationally, it's the difference between managing FX and just explaining it.

In the next blog, we look at what happens to reconciliation when your payment stack grows, and why adding PSPs quietly hands finance a new monthly problem to solve.