The Short Answer

Swap — also called the rollover fee — is the interest you pay or earn for holding a forex position overnight past the broker's daily cutoff, usually 5 PM New York time. It exists because every currency pair involves borrowing one currency to buy another, and each currency carries its own central bank interest rate. The difference between those two rates determines whether swap is a credit or a debit on your account. If you buy a high-yielding currency with a low-yielding one, you earn the difference; reverse the trade and you pay it. Swap is applied to every position left open at the rollover point.

How Swap Is Calculated

The raw swap rate comes from the interest rate differential between the two currencies, adjusted by your broker's markup. For example, if you are long AUD/JPY, you earn Australia's higher rate while paying Japan's near-zero rate — a positive carry that credits your account each night. Go short the same pair and the flow reverses into a daily debit. Brokers express swap in points per lot in their contract specifications, so a quick check before trading shows the exact daily cost. Because central banks shifted rates aggressively through 2024 and 2025, swap values on pairs like USD/JPY changed dramatically — always check current specifications rather than relying on memory.

The Wednesday Triple Swap Explained

Beginners are often startled by a Wednesday charge three times larger than usual — this is the triple swap, and it is completely normal. Forex trades settle two business days after execution (T+2), so a position held through Wednesday night rolls over the weekend, when banks are closed but interest still accrues. Brokers account for Saturday and Sunday by charging three days of swap on Wednesday. Day traders who close everything before the daily cutoff never pay swap at all, which is one reason intraday styles are popular. If you hold swing trades for weeks, these small daily amounts compound into a meaningful part of your costs — check them alongside the spread.

Swap-Free (Islamic) Accounts and Carry Strategies

Many brokers offer swap-free accounts, often called Islamic accounts, that waive overnight interest to comply with Sharia principles — though some add a fixed administrative fee per night instead, so read the terms. Beyond compliance, swap itself can be a strategy: carry trading means deliberately buying high-yield currencies funded by low-yield ones to collect the daily differential, a tactic that works best in calm markets and suffers in risk-off selloffs. For everyone else, swap is simply part of the holding cost. New to the basics? Start with what a pip is and a beginner's guide to forex before worrying about carry.

Frequently Asked Questions

When exactly is swap charged? At the broker's daily rollover, typically 5 PM New York time — any position open at that moment incurs one day of swap. Can swap be positive? Yes: buying the higher-yielding currency in a pair credits your account each night you hold it. Do I pay swap on weekends? No direct weekend charges exist; instead, brokers apply three days of swap on Wednesday to cover Saturday and Sunday. Check your broker's contract specifications for the exact triple-swap day, as some brokers apply it on Friday instead.