Exness publishes its swap rates daily, and I will concede upfront that those numbers are not fabricated.
Now let me tell you why that concession matters far less than it sounds. The swap line sitting in your MT5 terminal — that single figure, long or short, credited or debited at server midnight — is the *output* of a calculation. The calculation itself contains at least three separate inputs, only one of which has anything to do with the actual interbank cost of holding a position overnight. The other two are markups. Your broker controls all three knobs. They publish the result. They do not publish the knobs.
This is the part that genuinely fascinates me about overnight rollover mechanics, and I think most forex education skips it because the underlying math looks boring. It is not boring. It is one of the most elegant ways a broker extracts revenue from a retail trader without the trader ever noticing, because the trader sees a line item called "swap" and assumes it reflects some immutable market rate handed down from the interbank gods. It does not.
The Formula Is Simple — The Inputs Are Where the Game Lives
The textbook overnight rollover calculation looks like this in every forex education module ever written: take the interest rate differential between the two currencies in the pair, adjust for contract size and current price, divide by 365 (or 360, depending on convention — and that choice alone changes the number), and arrive at a theoretical swap value. If you are long a currency with a higher interest rate than the one you are short, you receive a credit. If the reverse, you pay. Simple.
That is the version your broker's FAQ gives you. It is technically correct in the same way that saying "a car runs on fuel" is technically correct — true, but missing the entire engine.
Here is where it gets genuinely interesting. The interbank rate differential is just the starting ingredient. Your broker then applies a markup to that differential. This markup is not standardized, not regulated by SEBI or RBI or any authority that governs offshore forex broker conduct toward Indian residents, and not disclosed as a separate line item. It is baked into the swap output. When you see "-7.2 points" next to your EUR/USD long position in MT5, you have no way of knowing whether 4 of those points are the interbank differential and 3.2 are the broker's revenue, or whether 2 are the differential and 5.2 are markup. The broker knows. You do not.
And this markup varies — not just between brokers, but within the same broker's account tiers.
Consider the spread architecture already visible in published data. Exness publishes a EUR/USD spread of 1.0 pip on its standard account and 0.1 pip on its pro account. That is a 0.9 pip difference in visible transaction cost between account tiers. The same structural differential exists in the swap schedule, but it is invisible because swap rates are published as a single number without decomposition. The published swap is never the interbank rate — it is the interbank rate plus whatever the broker decided to add, and that addition is the broker's overnight revenue model.
FXTM, with its EUR/USD standard spread of 1.5 pips and pro spread of 0.1 pip, demonstrates an even wider visible gap between tiers — 1.4 pips. That visible spread difference tells you something about FXTM's revenue structure on the transaction side. The swap side has an equivalent gap, but you would need to compare FXTM's published swap against the raw Tom/Next rate from the interbank market on the same day to isolate it. Most retail traders in India never do this comparison because the Tom/Next rate is not in their MT5 terminal and their broker's education centre does not mention it.
Your Islamic Account Escapes the Swap Line but Not the Math
Here is where the behind-the-scenes machinery becomes genuinely fascinating, and I want to spend more time on this than most articles would because the mechanics deserve it.
Every broker in the dataset offers Islamic accounts. Exness, FXTM, HF Markets — all of them. The premise is straightforward: overnight swap charges involve interest, interest involves riba, riba is prohibited, therefore the swap line disappears from Islamic accounts. The trader sees no swap debit, no swap credit, and concludes that overnight holding costs are zero.
They are not zero. They are relocated.
The broker still incurs the cost of holding your position overnight. The liquidity provider from whom the broker sources its pricing — or, if the broker is B-booking your trade, the broker's own hedging desk — faces the same interbank rate differential regardless of whether your account is labeled Islamic or conventional. That cost does not evaporate because of an account setting. It moves.
Where it moves is the part most traders never investigate. The compensation mechanism varies by broker and is usually disclosed somewhere in the Islamic account terms of service, but rarely in the same document as the swap schedule. Exness, regulated by the FCA among others, publishes Islamic account conditions separately from its standard swap schedule. HF Markets, regulated by the DFSA in addition to the FCA and CySEC, similarly publishes separate terms. When you read the standard swap schedule, it says one thing: here are your nightly swap rates. When you read the Islamic account supplement, it says something adjacent but different: here are the conditions under which overnight positions are held without swap, including any applicable charges. Two documents from the same broker, covering the same overnight cost, arriving at different numbers.
The practical mechanisms typically include a widened spread applied only to Islamic accounts, an "administration fee" charged per lot per night held, or a "financial charge" that appears after a grace period of several days. The critical insight is what happens when you run the effective cost calculation. HF Markets publishes a EUR/USD standard spread of 1.2 pips and a pro spread of 0.0 pips. On a conventional pro account, the trader pays 0.0 pip spread plus commission plus a known swap. On an Islamic pro account, the trader pays 0.0 pip spread plus commission plus whatever the Islamic account mechanism adds. Published spread: 0.0 pips. After commission on a pro account: the broker's stated commission rate. After Islamic account overnight holding charge: a figure that regularly exceeds the conventional swap it replaced, because the broker recovers the same revenue plus a risk premium for the operational complexity. That last number — the effective overnight cost after Islamic markup — is the one to remember, and it is the one almost nobody calculates because the phrase "swap-free" creates a cognitive shortcut that feels like "cost-free."
Wednesday Is Not One Night — It Is the Most Expensive Night of the Week
There is one more mechanical detail that I find endlessly interesting and that most rollover explanations either skip or mention in passing without explaining *why*.
The Wednesday triple swap.
Forex settles on a T+2 basis. When you hold a position through Wednesday's server rollover, the settlement date moves from Friday to Monday — skipping Saturday and Sunday. The broker charges three nights of swap for that single rollover event. This is not a broker invention or a revenue trick; it is a genuine settlement convention inherited from the interbank FX market. But here is what makes it acutely relevant to the retail trader running positions on MT5 through an offshore broker: the triple swap on Wednesday means that the effective weekly swap cost is not swap multiplied by five — it is swap multiplied by seven, compressed into five trading days, with three-sevenths of the total concentrated on a single night.
For a trader holding positions for several days — not a scalper, not a day trader, but someone running a swing position on gold or EUR/USD — Wednesday's rollover is the single largest line item in their weekly cost structure. And if that trader is on an Islamic account, the Wednesday mechanism depends entirely on how the broker's Islamic account terms handle the settlement convention. Some brokers charge triple the administration fee on Wednesday. Others spread the cost across the week. Others apply no additional charge for three days and then levy a lump-sum "financial charge" after a holding period ends. The inconsistency between brokers is itself a cost, because it makes comparison functionally impossible without pulling each broker's Islamic account terms side by side and doing the arithmetic manually.
Exness with its 0.1 pip pro spread, FXTM with its 0.1 pip pro spread, HF Markets with its 0.0 pip pro spread — all three show nearly identical visible transaction costs at the pro tier. The spread column suggests they are interchangeable. The swap schedule introduces the first divergence. The Islamic account terms introduce the second. And the Wednesday multiplier amplifies whichever of these layers carries the overnight cost, turning a small daily difference into a meaningful weekly one for any position held through midweek.
This started as a piece about a formula — the kind of thing you might expect between "how do I deposit funds" and "what is a pip" in a broker's FAQ. It turned into something else, because the formula is the least interesting part of overnight rollover. The interesting part is everything the formula does not show you: the markup baked into the published swap, the relocation of that cost into Islamic account mechanisms that use different names for the same revenue, and the Wednesday compression that makes one calendar night cost three settlement nights. The math is simple. The inputs are where the game lives.
HF Markets is regulated by the DFSA, the FCA, CySEC, and the FSCA. Its Islamic account terms are published separately from its swap schedule. Those are two documents, from the same broker, covering the same overnight cost, arriving at different numbers. That is the gap.