Spot settlement T+2 and position rollover — where swap comes from

You buy EUR/USD on a Tuesday afternoon and everything seems instant — the price, the position, the running result ticking on screen. Yet the actual exchange of euro for dollars, were it ever to happen, would only settle on Thursday. That is the spot convention: you agree the price today, delivery of the currency lands two business days later. As a speculator you never want those dollars delivered, so the broker quietly moves the deadline forward for you every day — and that move is what you see on the account as the swap. Below I explain where the mechanism comes from and why it matters to your bottom line.

What a "T+2 value date" actually means

A spot trade carries two distinct dates. The first is the trade date, the moment you agree the rate and click buy or sell. The second is the value date — the day on which both accounts are actually credited and debited in the two currencies. On most currency pairs those two dates are two business days apart. Hence the shorthand T+2: a trade struck today settles two sessions later.

Why the delay? Because delivery of currency is two separate payments in two banking systems, often on opposite sides of the globe. Once the rate is agreed, both sides have to confirm the terms, send payment instructions and move funds to the right accounts. Two business days is an operational buffer rooted in time-zone gaps and the genuine time it takes to clear a settlement. At the wholesale level these payments today mostly run through payment-versus-payment infrastructure — according to the description of CLSSettlement, roughly eight trillion dollars of currency payments settle there each day. That is where, two days after your click, the value date would close.

Why holding a position overnight triggers a rollover

And here is the catch. Since every spot trade heads toward delivery at T+2, a position you leave open overnight drifts toward that date. If it reached the value date with no action, it would in theory require a real exchange of one hundred thousand euro for dollars. No retail trader wants that — you opened the position for the price move, not to become an owner of currency.

The answer is a rollover. Each day, at a conventional cut-off time — 5 p.m. New York time — the broker closes the old value date and opens a new one, shifted one day forward. Operationally it looks like simultaneously settling the position for today and reopening it for tomorrow, known in the trade as a tom-next transaction (from tomorrow and next day). Delivery therefore never arrives, and you hold the exposure for as long as you like. You pay for that with the interest-rate differential between the two currencies.

Where the swap comes from, exactly

The rollover is not free, because each currency in the pair has its own central-bank interest rate. Holding a position, you are in effect borrowing one currency and depositing the other. You pay interest on the one you borrow and earn it on the one you hold. The tom-next settles that difference every day — and that is what appears on the account as the swap point. Put plainly: the swap is not a separate fee dreamed up by the broker, it is the price of shifting the value date. I break that same account line into its components in the piece on what a forex swap is.

The sign of the swap depends on the direction of the rate gap. If the currency you hold in the position earns more than the one funding it, the swap can be positive and credits the account. The other way round, it debits you every day. To the raw rate gap the broker adds its mark-up, so a real retail swap is usually less favourable than the pure rate arithmetic. Let us trace it through one simplified example.

Brokers usually quote the figure in the instrument specification as pips per lot per night. To see the real cash cost, you multiply that value by the pip value and by the number of nights. If the long swap on EUR/USD is minus three and a half pips, and the pip value is ten dollars per lot, one night costs thirty-five dollars — and Wednesday, as we are about to see, costs three times that.

"Spot value settles two business days after the trade date. Positions carried beyond that date are rolled over, and the cost of the roll reflects the interest-rate differential between the two currencies." — Brian Coyle, Currency Risk Management, Routledge, 2000.

T+1 exceptions and the Wednesday triple swap

The T+2 convention is not universal. Some pairs settle faster, at T+1 — the next business day. The headline case is USD/CAD: the US and Canadian dollars share a time zone and overlapping banking hours, so settlement closes a day earlier. The same applies to pairs such as USD/TRY. This is more than trivia: a shorter settlement cycle means the value date sits differently against the weekend, which changes the day of the triple charge.

Because the weekend is exactly what explains the famous Wednesday triple swap. A position held from Wednesday into Thursday has its value date set under T+2 to Saturday, and banks do not settle on Saturday. The value date therefore jumps to Monday, picking up two extra calendar days on the way. The interest for Saturday and Sunday still has to be charged, and it is charged in advance, on Wednesday — so the Wednesday swap equals three normal daily accruals. I set this out day by day in the article on the triple swap on Wednesday, including the instruments that take their triple charge on a different weekday.

What this means for your trading style

The first takeaway is practical: if you close every position before the rollover time, the swap never touches you. A scalper or day trader who holds nothing overnight neither pays nor receives swap — their trades finish long before 5 p.m. New York. That is a genuine cost edge of intraday-only trading, one that beginners often overlook while counting only spread and commission.

The second takeaway is about CFDs. A contract for difference never heads toward delivery of currency — it is an agreement with the broker settled purely in cash. And yet the broker replicates spot financing: it charges or credits each day an amount matching the interest-rate differential, exactly as a rollover on the underlying market would. A CFD therefore inherits the economics of the T+2 roll even while skipping its legal cause. How that contract differs from real delivery on a futures exchange, I work through in the comparison of spot and futures contracts, and the logic of a market with no exchange in the piece on how the OTC market works. For the wider groundwork on how a spot trade is structured before any of this financing applies, the forex basics section on ForexMechanics goes deeper.

What to do tomorrow

1. Check the value date and swap in the instrument specification. Open the platform, right-click the pair you trade, go into the specification and note the long and short swap values. Before you click buy or sell, you need to know whether holding overnight will cost you or pay you — that is a difference of tens of dollars a month on a single lot.
2. Compute the rollover cost for your holding horizon. Multiply the daily swap in pips by the pip value and by the number of nights you plan to hold, remembering that Wednesday counts triple. If you intend to keep a trade for ten days and the swap is negative, add that cost to your break-even point before you enter the market.
3. Decide consciously whether you leave a position overnight. If your strategy finishes within the day, close everything before the 5 p.m. New York rollover and you avoid the swap entirely. If you hold longer, treat the swap as a fixed component of the result rather than a minor detail — on weekly positions it can decide whether the strategy makes economic sense at all.
4. Look at the central-bank meeting calendar. Write the next Fed, ECB and Bank of England decision dates into your calendar. A change in the policy rate moves the swap from one day to the next, so if you hold a long-horizon position built on a rate differential, those dates matter more to you than most technical signals.