Direct answer
Rollover for EUR/USD is the interest-related adjustment added or subtracted when a position is held beyond a standard daily cut-off time. The core idea is simple: it reflects the difference between the interest you would receive on the currency you are effectively long and the interest you would pay on the currency you are effectively short, expressed as an amount on your trade’s notional value. In practice, the final number also depends on how a provider converts interest rates into a daily figure, any provider adjustments (for example, markup or swap-rate setting), and special “triple-swap” handling over certain days.
Mechanism and definition
To explain rollover mechanics for EUR/USD, it helps to separate stable concepts from variable inputs.
1) Interest-rate differential (the stable part) EUR/USD is a spot FX pair, but rollover is usually computed from underlying short-term rates associated with each currency. If you hold a position long EUR/USD (buy EUR, sell USD), the position is treated as if you are long EUR and short USD; the direction determines whether the swap is typically credited or charged, depending on which currency’s rate is higher.
2) Converting an annual rate into a daily amount (the operational part) Swap is typically calculated per holding day. Providers convert relevant rates into a daily figure using:
- a day-count convention (how an annualized rate is transformed into a fraction per day),
- the instrument’s contract size and your position size (notional exposure),
- then a scaling step to express the result in the account currency.
Because providers may use different conventions or intermediate calculations, two accounts could see different rollover amounts even with the same general interest-rate environment.
3) Provider adjustments (the variable part) Even if the idea is based on an interest-rate differential, the “off the shelf” number shown on a platform is not guaranteed to be the pure theoretical differential. Providers may set swap rates based on their own pricing, spreads, internal funding assumptions, or risk costs. As a result, the observed rollover is the provider’s implementation of the interest concept plus any adjustments.
4) Triple-swap (a scheduling exception) Many FX implementations apply a larger rollover on a specific day to cover weekend or non-business periods. In that case, the daily swap effect is multiplied (commonly described as a “triple-swap”) for the relevant holding window. The key is not the label, but that the provider uses a schedule where the number of “swap days” can change when you hold over certain cut-off times.
Evidence or example (with explicit assumptions)
A rollover model can be represented as:
Rollover amount ≈ Notional × Daily rate differential × Number of swap days −/＋ Provider adjustments
Here is an illustrative example that shows the moving pieces without pretending it matches any specific platform:
- You hold a EUR/USD position of notional €100,000.
- Assume the provider converts an annualized differential into a daily differential of D (whatever formula it uses internally).
- Assume the rollover is charged or credited based on the differential and then applied over N swap days.
Case A (ordinary day): if you cross the cut-off and N = 1, then rollover is approximately €100,000 × D (with the sign determined by your long/short direction and the provider’s setting).
Case B (weekend handling): if you hold over a period where the schedule sets N = 3, then the rollover is approximately €100,000 × D × 3.
The important assumption is that D and the adjustment term come from the provider’s internal swap-rate setup and conventions. Because those details are account- and provider-specific, a reader should treat any numerical “how-to-calculate” example as a template, not as a direct prediction of what will appear on their statement.
Limitations and risks (what can go wrong)
- Provider-specific inputs: The daily conversion method and any markups or adjustments can differ. Even when the interest-rate differential logic is consistent, the displayed rollover can be different. 2) Timing and cut-off dependence: Rollover is tied to when you cross the provider’s cut-off time. Holding a position across different cut-off windows changes whether you get N=1 or N>1 swap days. 3) Account and contract details: Contract size, quote/base currency conventions, and rounding rules can affect the final posted amount.