Currency Hedging Cost: How to Calculate the True Price of Protecting FX Exposure
Hedging a foreign-currency receivable or payable with a forward contract locks in today's rate for a future date. It is not free: you pay the gap between the forward and spot rates (as a fraction of spot), the dealer's spread, and a small cost for keeping the position open. On a $500,000 exposure with spot 1.1000, forward 1.1120 and a 0.30% spread over 90 days, the estimate is about $7,078, or 1.4% of the amount protected. This guide shows the calculation and how to use it.
What Hedging Cost Is
Hedging cost is what you pay to remove exchange-rate risk on an exposure for a set period: the premium for certainty. By locking in a rate you give up any favorable move and accept a known expense in exchange for eliminating the downside.
Leaving the exposure open has a cost too, just an uncertain one. If you are owed €1 million in three months and the euro weakens 5% against your home currency before it arrives, the receivable loses 5% of its value (€50,000 worth at today's rate). The decision is a comparison between that unpredictable loss and the hedge's predictable cost, and between instruments: a forward, an option or no hedge at all.
How to Calculate the Hedging Cost
The Currency Hedging Cost Calculator combines three components:
Total cost = Exposure × (Forward − Spot) ÷ Spot × Direction + Exposure × (Spread% ÷ 100) + Exposure × 0.001 × (Days ÷ 365)
The exposure is its value in your home currency at today's spot rate, and both rates are quoted as home currency per unit of the foreign currency (for a US company hedging euros, dollars per euro). The first term is the forward differential: the gap between the locked-in forward rate and today's spot rate, expressed as a fraction of spot so the result is in your home currency whatever the quote level. Direction is +1 when you buy the foreign currency forward (a payable) and −1 when you sell it forward (a receivable): a forward premium is a cost to the buyer and a gain to the seller. The second is the broker spread, the dealer's markup as a percentage of the exposure. The third is a time-prorated holding cost that the calculator fixes at 0.1% per year to represent margin, credit and administration; it is a modeling assumption, not a market rate.
Worked example. A US company hedges a payable worth $500,000 at today's spot rate for 90 days, buying the foreign currency forward. Spot is 1.1000 dollars per unit, the forward rate is 1.1120 and the broker spread is 0.30%.
1. Forward differential: 500,000 × (1.1120 − 1.1000) ÷ 1.1000 = 500,000 × 0.010909 ≈ $5,455
2. Broker spread: 500,000 × 0.003 = $1,500
3. Holding cost: 500,000 × 0.001 × (90 ÷ 365) = 500,000 × 0.000247 ≈ $123
4. Total: $5,455 + $1,500 + $123 = $7,078 (rounded to the dollar at each step)
That is about 1.42% of the exposure. Enter the same inputs with the "3 Months" period and the payable (buying forward) option to reproduce it. For a receivable sold forward at the same rates, the first term becomes a gain and the calculator returns about −$3,831. If you only want the forward-differential term and are hedging part of the exposure, the Currency Hedging Calculator multiplies that term by a 25–100% hedge ratio, with the same payable or receivable choice.
Where the Forward Rate Comes From
The forward-spot gap is not a dealer's opinion about where the currency is going. Under covered interest rate parity, the forward rate is set by the interest-rate differential between the two currencies: F = S × (1 + i_quote × t) ÷ (1 + i_base × t), where the rates are for the contract period. Anything else would allow risk-free arbitrage between borrowing in one currency and depositing in the other. The currency with the higher interest rate trades at a forward discount, so a hedge that locks in the lower-rate currency's forward premium "pays away" that differential, and a hedge in the other direction earns it.
Using the Number
Cost versus open risk. Weigh the $7,078 against a plausible adverse move on $500,000 over 90 days. If a realistic move dwarfs the cost, protection is cheap; if the pair is stable and the cost is high relative to the downside, staying open or hedging a fraction may be better.
Shop the spread. The spread is the most negotiable component. A few basis points matter on large exposures.
Match the term to the exposure. A longer hedge locks in the differential for longer and raises the holding term. Hedge to the date the cash actually moves.
Compare with an option. A forward is cheaper but obligates you; an option costs a premium but keeps the upside. The forward cost estimate gives you the number to compare against the premium.
The estimate is directional: real forward pricing, credit terms and liquidity vary by dealer and by day, and this page is not financial advice.