Spot Rate vs Forward Rate: Difference, Formula and Examples

Key takeaways

• Spot rate: today's exchange rate, settled within two business days (T+2).
• Forward rate: fixed today for a future date, worked out from spot and the interest rate gap, so it is not a forecast.
• The gap between them is the forward premium or discount: with spot at ₹95, a three-month USD/INR forward comes to about ₹95.46.
• Use spot for payments now and a forward for known future payments.
• In bonds, the terms mean today's interest rate and the rate implied for a later period.

The spot rate is the price to exchange one currency for another today, with settlement usually within two business days, while the forward rate is a price agreed today for an exchange on a set future date. The spot rate moves with the market; the forward rate is fixed once you agree it.

In foreign exchange, dealers call these FX spot and FX forward trades, and the places they happen the spot market and the forward market.

Is the spot rate the same as the forward rate? No. They are usually close, and the gap grows with time to the future date. The spot rate is what you see as today's forex rates; the forward rate is a contract price your bank quotes for a later date.

An Indian software firm will receive $10,000 from a US client in three months. The spot rate today is ₹95 per dollar, and the bank offers a three-month forward rate of ₹95.46. These rates are illustrative.

If the firm waits and converts at the spot rate when the money arrives, it gets whatever the rate is that day. If it books the forward today, it will receive ₹9,54,600 in three months, whatever happens to the rupee.

That is the spot rate vs forward rate trade-off in one example: the forward removes the risk of the rupee strengthening, at the cost of missing the gain if it weakens.

To get the forward exchange rate, adjust today's rate for the interest rates of the two currencies over the period:

Forward = Spot × (1 + quote-currency rate × days/365) ÷ (1 + base-currency rate × days/365)

1. Write the pair as base/quote. In USD/INR, the dollar is the base and the rupee is the quote.
2. Take the interest rate of each currency for the period, here 6% for the rupee and 4% for the dollar.
3. Scale each rate to the period: for three months, 6% × 90/365 = 1.48% and 4% × 90/365 = 0.99%.
4. Apply the formula: 95 × 1.0148 ÷ 1.0099 = ₹95.46, the rate used in the example above.

The rule behind it is simple: the currency with the higher interest rate trades at a lower forward rate, so no one can earn a risk-free profit by borrowing in one currency and lending in the other. That is why a forward is not a forecast of where the rate will go. Banks also add their margin, and the gap between their buying and selling rates widens for longer periods.

In currencies, the gap is called the forward premium or discount, measured in points. In commodities, the same gap is called the basis.

So with spot at ₹95 and a forward of ₹95.46, the dollar is at a forward premium of 46 paise, or 46 forward points in paise terms. In commodities, the same gap has another name: if lettuce costs $50 a case today and $55 for July delivery, the $5 difference is the basis.

The lower-interest-rate currency is the one at a premium. With the dollar at 4% and the rupee at 6%, the dollar trades at a forward premium against the rupee.

Indian banks usually quote it as an annualised premium: (forward rate minus spot rate) ÷ spot rate × 365 ÷ days × 100. In the example, (95.46 minus 95) ÷ 95 × 365 ÷ 90 × 100 is about 2% a year, roughly the gap between the two interest rates.

In bonds and loans, the spot rate is what you earn on money lent from today until a set date, such as the yield on a two-year zero-coupon bond. The forward rate is what a period starting later must earn, as implied by today's rates.

The idea is easiest to see with two ways of investing ₹100 for two years when the one-year spot rate is 2% and the two-year spot rate is 3%:

Both options must end at the same value, or investors would all pick the better one. So the second-year rate must be 106.09 ÷ 102 minus 1, which is 4.01%. That is the one-year forward rate starting in one year: forward rate = (1 + two-year spot)² ÷ (1 + one-year spot) minus 1.

When longer-term rates are higher than short-term ones, as here, the yield curve slopes upward and the implied future rates sit above today's; when it slopes downward, they sit below. Bond investors use these implied rates to judge whether to lock in a longer bond or roll over shorter ones.

Use the spot rate when money is needed now or the amount is small; use a forward contract when you know you will pay or receive a foreign currency on a future date and want a fixed rupee amount.

• Use spot: an invoice due this week, an unplanned payment, or amounts too small to justify a contract
• Use a forward: an exporter's confirmed receivable or an importer's payable due in one to twelve months, or when the margin on a deal cannot absorb a currency move
• Use neither alone: when the timing or amount is uncertain, hedge only the part you are sure of

In India, forward contracts involving the rupee can be booked only to hedge a genuine currency exposure, contracted or expected, through your bank, under RBI's risk-management rules effective 5 April 2024. If the client pays late, ask the bank to extend the contract; if the deal falls through, the bank cancels it and you settle the difference between the forward rate and the market rate. See FX hedging for the options.

For exporters collecting payments from abroad, Xflow's FX AI Analyst shows USD/INR trends, and Limit Orders let you set a target rate so the conversion runs when it is reached, at the live mid-market rate.