You buy for a certain amount and, if you try to sell immediately, you realise that you receive less money back. This difference is not an error or a surprise penalty: it is called spread.
Every time you open a position in the stock market, in Forex or in the cryptoasset market, you assume a cost that rarely appears as an explicit commission on your screen. Consequently, the spread acts as an implicit margin that is charged between the price at which you buy an asset and the price at which you can sell it at that very instant.
Although at first glance it may seem an insignificant percentage, this invisible cost accumulates quickly when you carry out frequent operations or use leverage. Therefore, understanding what it is, why it exists and how it affects your money is one of the essential pillars for managing your transactions with true strategy and professional judgement.
What the spread is
The spread is the difference between the price at which you can buy an asset (Ask) and the price at which you can sell it (Bid) at that very instant.
In practice, this differential works as an implicit cost in every transaction that allows platforms and intermediaries to obtain their profit margin. Likewise, the size of this gap offers direct information about market conditions:
- Narrow spread: It reflects greater liquidity and lower volatility, reducing your costs when trading.
- Wide spread: It indicates lower liquidity and greater volatility, increasing the implicit cost of the transaction.
Buying price and selling price
To calculate the spread, the two official market prices are used:
- The Ask (Selling price): It is the amount you pay if you buy immediately.
- The Bid (Buying price): It is the amount you receive if you sell instantly.
Spread = Ask Price – Bid Price
Starting from this formula, the transaction is only executed when buyer and seller match their offers. Thus, if demand presses, the price rises seeking a higher Ask; if supply dominates, the offers fall until finding a Bid willing to buy.
An example you already know: the airport exchange office
To understand how the spread works in everyday life, there is no need to look at complex trading charts, it is enough to remember how the airport exchange office works.
When you travel abroad and approach a currency exchange window, you immediately observe a panel with two prices for the same currency: the buying price and the selling price. If you buy dollars with euros and, due to some unforeseen event, you decide to return them at that very instant, you will verify that you receive fewer euros than you handed over seconds before.
That price difference is nothing more than the spread applied by the exchange office to cover its operating costs and obtain its profit margin. In the same way as when exchanging currency to travel, in the cryptocurrency market exchanges and trading platforms apply this same principle implicitly in every transaction.
Why the spread exists
In the financial sector, the spread is not an abusive charge, but the basis of the business model of intermediaries. By offering immediate liquidity so that you can buy or sell at any instant, the provider assumes operating costs and risks that it compensates through this differential:
- Market risk: The intermediary acquires assets without absolute guarantee of at what price it will be able to sell them in the next minute.
- Liquidity cost: It requires keeping a large amount of capital immobilised in various assets to respond immediately to users’ demand.
- Operating costs: Maintenance of technological infrastructure, cybersecurity, personnel and regulatory compliance.
For this reason, digital platforms usually offer much tighter spreads than traditional banking entities, as they have lower physical structure costs and greater operating efficiency.
Liquidity
Firstly, liquidity represents the ease with which an asset is bought or sold without drastically altering its price. In high-demand cryptocurrencies (such as Bitcoin or Ethereum), the constant volume of buyers and sellers allows the spread to be minimal. On the contrary, in tokens with lower trading volume, the scarcity of offers widens the gap between the Bid and the Ask.
Volatility
On the other hand, the speed and magnitude with which the quotation of a cryptoasset fluctuates impact directly on the differential. In moments of high fluctuation in the market, providers increase the spread to protect themselves from abrupt price changes before being able to liquidate the position.
The provider’s margin
Finally, the spread integrates the platform’s net profit for providing the intermediation service. While some entities apply visible fixed commissions for each transaction, others prefer to adjust this implicit margin in the offered price, allowing immediate orders to be executed with total clarity on the final amount to be received.
Spread, network commission and service commission
When carrying out transactions with cryptocurrencies, it is common to confuse the different amounts involved in the operation. However, to properly manage your costs it is essential to differentiate the implicit market margin from the explicit charges for infrastructure and service.
In the following table you can clearly see what each concept represents and how it impacts your balance:
|
Type of cost |
What is it? | Who is it addressed to? |
Visibility in the operation |
| Spread | Differential between the Ask and the Bid. | To the provider or exchange as operating margin. | Implicit: Included directly in the final price offered. |
| Network commission (Gas Fee) | Fee required to process and validate the transaction on the blockchain. | To the miners or validators of the network (not to the platform). | Explicit: Variable according to network congestion. Consult the network fees guide. |
| Service commission | Fixed or percentage fee charged by the platform for processing the sale. | To the intermediation platform for managing the service. | Explicit: Broken down before confirming the order. |
How to see how much you pay before buying
To avoid surprises, the best financial habit is to always compare the final amount to be received against the reference quotation price in market aggregators.
- Review the current market price: Observe the theoretical average quotation in aggregators.
- Check the confirmation screen: Before authorising the order on your platform, look at the exact amount of cryptoassets (or euros) that will be credited to your wallet.
- Calculate the difference: Subtract the global value of what you hand over minus what you effectively receive. That final gap encompasses both the spread and the fixed service commissions.
The spread in crypto versus stock market and currencies
The behaviour of the spread varies considerably according to the maturity and structure of each financial market:
- Currency market (Forex): It is the most liquid market in the world. It operates with extremely narrow spreads in major pairs (such as EUR/USD), measured in minimal fractions.
- Stock market: In large-cap shares the differential is minimal thanks to the high constant volume. In small companies, the spread widens due to lower liquidity.
- Cryptocurrency market: It operates 24 hours a day, 7 days a week. Due to this continuous operability, the spread can fluctuate significantly depending on the volume in each time slot, being very narrow in major assets such as Bitcoin and considerably wider in tokens with lower capitalisation.
Frequently asked questions about the spread
- Is the spread a commission? Not in the strict sense. It is not an explicit fixed fee, but an implicit cost integrated directly into the buying or selling price offered by the provider.
- Why does the spread change throughout the day? Due to changes in liquidity and volatility.
- What is a high spread? It is a wide gap between the Ask and the Bid price, which indicates that the market has low liquidity or high volatility, making the cost of your operation more expensive.
In short, understanding how the spread works allows you to make more efficient buying decisions and avoid unnecessary costs in your transactions. Although it is an element inherent to the operation of any financial market, choosing platforms with high liquidity and transparent fees will guarantee that you preserve the maximum value of your capital in each operation.