Overnight Financing

What is overnight financing?

Overnight financing is the umbrella term for the cost of holding any leveraged position — forex or CFD — beyond a single trading day. In forex, this cost is usually called swap and is driven by the interest-rate differential between the two currencies in a pair. On CFDs over other assets — indices, shares, commodities — the same underlying idea applies: because you’re only putting up a fraction of the position’s full value as margin, the broker is effectively financing the rest, and that financing has a cost (or, less commonly, a small credit) for as long as the position stays open past the daily rollover.

How it’s typically calculated

Overnight financing on non-forex CFDs is commonly calculated using a benchmark short-term interest rate for the relevant currency (such as a central-bank policy rate or an interbank reference rate) plus or minus a broker markup, applied to the notional value of the position held overnight. The exact formula, markup, and reference rate vary by broker and instrument, so the specific calculation should always be checked in a broker’s own documentation rather than assumed.

As an illustrative example only: a trader holding a leveraged index CFD position worth $50,000 overnight, where the applicable annualized financing rate works out to a few percent, would see a proportionally small daily charge — roughly the annual rate divided by 365 and applied to the position’s full notional value, not just the margin put up.

Why it matters

Overnight financing is a real cost that accumulates the longer a leveraged position is held, which is why CFDs and leveraged forex are generally better suited to short-to-medium-term trading than to very long-term “buy and hold” investing — the daily financing charge can meaningfully erode returns over weeks or months if the underlying price doesn’t move enough to offset it. It’s a cost that sits alongside the spread or commission paid at entry, and should be checked for any position a trader plans to hold for more than a day or two.

Quick recap

• Overnight financing is the broader term covering swap costs across all leveraged instruments, not just forex.
• It reflects the cost of the broker effectively funding the leveraged (borrowed) part of a position.
• Rates and calculation methods vary by broker and instrument — always verify the specific figures.
• It’s a key reason leveraged CFDs are generally used for shorter holding periods.