How a floating rate swap can change between the quote screen and the confirmation

05 September 2026

The quoted price for a floating rate swap can differ from the final confirmation because the underlying market rate moves in the seconds between the two screens. This is not a bug or a hidden fee; it is the normal behavior of a swap tied to a live, changing reference price.

Here is how it works.

A floating rate swap uses an external price feed - typically an aggregate of exchange rates from several markets - to determine the conversion rate at the moment of execution. When you first see a quote, that rate is a snapshot taken at that instant. The swap is not executed yet. You are being shown an estimate, not a locked price. The actual rate will be set when the transaction is broadcast to the blockchain and confirmed.

The delay between the quote and the confirmation can be short - often under a minute - but even a few seconds matter in cryptocurrency markets. Prices shift constantly. A 0.1% movement in a major pair is common. In volatile conditions, the change can be larger. The swap provider has no control over this. It simply reads the market rate at the time of execution and applies it.

The gap between quoted and received amounts is therefore a function of market movement, not of spread or network fees. Those costs are separate. The spread is the difference between the buy and sell price the provider offers, and it is usually fixed in the quote. Network fees are paid to miners or validators, not to the swap provider. Both are factored into the quote you see first. But the floating rate itself is not fixed until the moment the swap settles.

Some providers offer a "slippage tolerance" setting. This lets you define a maximum acceptable deviation from the quoted rate. If the market moves beyond that threshold, the swap will fail rather than execute at a worse rate. That is a safeguard, not a guarantee. Without it, the swap will go through at whatever the market rate is at confirmation time, even if that rate is worse than the quote.

The key point is that a floating rate swap is always a live trade. The quote is a preview. The confirmation is the actual trade. The difference between them is the distance the market traveled in the interval.

This is one of several costs that can change what you ultimately receive. The hub page "What a crypto swap actually costs" explains all the components: the spread, the network fee, and the floating rate effect. That page is the natural next read if you want to see how each piece fits together.

In practice, the difference is usually small for stable pairs or low-volatility periods. But it can be significant during rapid price moves, news events, or low-liquidity hours. The honest answer is that you cannot know the exact final amount until the swap confirms. You can only know the range of possible outcomes, which is determined by the volatility of the pair and the speed of the network.

No provider can eliminate this. It is inherent to a floating rate mechanism. The alternative is a fixed-rate swap, which locks the price at the quote but often includes a wider spread to compensate the provider for the risk of market movement. Fixed rates are less common in cryptocurrency swaps because the market moves too fast for most providers to hedge reliably.

So the change between the quote screen and the confirmation is simply the market doing what markets do. It is not a trick. It is not a fee. It is the price of using a live reference rate instead of a fixed one.

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