Forex and CFD positions are traditionally settled two business days after the trade date. If you hold a position open past the daily rollover cutoff, the settlement date effectively rolls forward, and the broker charges or credits a financing amount to reflect the interest rate differential between the two currencies (or the financing cost of the leveraged position) for that extra day.
Why Swap Exists
In the underlying interbank market, holding a currency position implies borrowing one currency to buy another. Each currency carries its own interest rate set by its central bank. If you're long a high-interest-rate currency against a low-interest-rate currency, you may earn a small credit; if it's reversed, you pay a charge. CFDs on stocks, indices, and commodities apply an analogous financing cost reflecting the leverage provided.
Triple Swap Days
Because most markets don't settle trades over the weekend, brokers typically charge three days' worth of swap on one specific day of the week (commonly Wednesday for forex, though this varies by broker and instrument) to account for the Saturday and Sunday that would otherwise be settlement days. This is a widely used industry convention, not a special penalty.
| Position type | Rate differential | Typical swap outcome |
|---|---|---|
| Long high-yield vs low-yield currency | Positive | Small credit, illustrative only |
| Long low-yield vs high-yield currency | Negative | Charge deducted daily |
| CFD on stock index (either direction) | Financing-based, not rate differential | Usually a charge on long, variable on short |
Suppose an illustrative long EUR/USD position carries a swap of minus 0.5 illustrative points per standard lot per night. Held for 30 nights, that alone represents an illustrative 15-point drag, separate from spread or commission. Actual swap rates vary daily by broker and are published in each platform's contract specifications.
Why Swap Matters for Strategy Selection
Day traders who close all positions before the rollover cutoff never pay or receive swap, making it largely irrelevant to their cost structure. Swing traders and position traders who hold for days or weeks accumulate swap as a real, recurring cost (or occasionally a benefit) that should be factored into the expected return of a trade, especially on pairs with a persistently negative differential in the trader's direction.
Islamic (Swap-Free) Accounts
Many brokers offer swap-free account variants, originally designed to comply with religious prohibitions on interest, that replace daily swap with a flat administrative fee or a wider spread instead. Traders should read the terms carefully, as swap-free does not always mean cost-free — the cost is often simply restructured.
Checking swap rates before holding overnight
Before holding any position overnight, it's good practice to check the instrument's current swap rate in the platform's contract specifications, since these rates change with central bank policy and can occasionally flip sign. A pair that historically paid a credit for a long position can start charging one after a rate cut.
- ▸Day traders can generally ignore swap since positions close before rollover.
- ▸Swing and position traders should include expected swap cost in their trade planning.
- ▸Swap rates are published per instrument and change regularly with interest rate policy.
- ▸Wednesday (or the broker's designated day) commonly carries triple swap to cover the weekend.