How rollover is calculated for USD/TRY

Direct answer

Rollover for USD/TRY (often shown as “swap” or “rollover”) is the cash adjustment made when you hold a leveraged FX position past a defined market cutoff. The core driver is the interest-rate difference between the two currencies (USD versus TRY). In practice, the amount you see is usually the pure interest gap, transformed into your contract’s quote terms, and then modified by provider conventions (for example, how the provider represents rates, and how it handles special rollover days).

Mechanism or definition

Rollover / swap is the interest-based adjustment applied to an FX position when it is rolled from one value date to the next. For a currency pair, the logic follows two steps:

Compute the interest-rate gap: conceptually, the “long” side of the pair earns interest while the “short” side is charged interest. For USD/TRY, the relevant comparison is the USD interest rate versus the TRY interest rate.
Convert the interest difference into a position P&L-like cash adjustment: the rate gap is multiplied by your exposure (notional/lot size), scaled by the time fraction (how many days are being rolled), and converted into the account/quote currency using the pair’s contract conventions (pip value, contract size, and the provider’s quote format).

Common inputs you must assume to calculate a number

Which day(s) the rollover covers: most implementations settle daily, but there can be a special case where the rollover includes extra days.
Day-count convention: interest calculations often use a defined day-count basis; without knowing it, you cannot reproduce a precise posted rollover.
Rate representation: providers may use quoted reference rates in a specific way (for example, averaging, compounding treatment, or mapping from a reference rate to an FX swap rate). You need the provider’s described method.
Contract scaling: the “swap per unit” depends on contract size and how the provider maps a rate to your instrument.

Triple-swap convention (the “extra days” exception)

Many FX rollover systems apply an extra rollover amount around a particular weekday, commonly described as a triple swap. The general idea is that the position’s holding period effectively spans more than one standard overnight period due to the market calendar and value-date mechanics. This means the “days factor” in the rollover calculation changes on that rollover day.

Evidence or example (with explicit assumptions)

Because the exact posted rollover depends on provider-specific conventions, the best way to understand the calculation is to work a simplified, educational example where you define every assumption.

Assume a USD/TRY position is held overnight for one standard rollover day.

Let the provider’s mapped USD reference rate (annualized) be r_USD.
Let the provider’s mapped TRY reference rate (annualized) be r_TRY.
Define the net interest gap for a long USD/TRY position as (r_USD − r_TRY) (conceptually: you benefit from the currency with the higher rate and pay the other).
Let notional be N in USD terms as expressed by your contract, and let a days fraction be d/DayCount.

A simplified educational structure is:

Net interest component ≈ N × (r_USD − r_TRY) × (d/DayCount)
Then converted into the instrument’s swap quote units (depends on pip/lot conversion rules)

Triple-swap example logic Now assume the position is rolled on a “special day” where the system uses an extra-day factor, so the days covered are d = 3 instead of d = 1.

If all else is equal, the interest component scales roughly with the days factor.
The posted rollover you see can therefore be much larger in magnitude (and possibly change sign only if the underlying interest gap changes, not just because it’s triple).

Where provider adjustments enter Even if you can build the interest-gap logic, the actual number shown to you can differ because providers may adjust:

the mapping from reference rates to tradable swap rates,
the instrument-specific conversion to “points” or account currency,
and any internal fees or pricing spreads embedded in swap quoting.

That is why two accounts or two providers can show different rollover amounts even when the underlying interest environment is the same.

Limitations and risks

You cannot reproduce exact posted swap without the provider’s documentation. The rollover rate mapping, day-count method, and conversion to your contract units are provider-specific.