The FX Bid-Ask Spread and Trading Costs

Key Takeaways

• The bid is the price you sell at; the ask is the price you buy at; the spread is the difference.
• The spread is your built-in cost on every round-trip trade, paid whether or not the trade is profitable.
• Majors have the tightest spreads; minors and exotics are wider, and all spreads widen in illiquid or volatile periods.
• For frequent, leveraged trading, spreads compound into a large drag that helps explain why most retail accounts lose money.

What It Is

Every forex quote has two prices. The bid is what the dealer will pay to buy the base currency from you (so it is the price you sell at). The ask (or offer) is what the dealer will charge to sell the base currency to you (the price you buy at). The ask is always higher than the bid.

The spread is ask minus bid, usually expressed in pips. If EUR/USD is quoted 1.10000 / 1.10005, the spread is 0.5 pips. You buy at 1.10005 and could immediately sell only at 1.10000, so you start each trade slightly underwater by the spread.

Why It Matters

The spread is how most retail forex brokers get paid, and it is a real cost regardless of outcome. Unlike a commission you might see itemized, the spread is baked into the price, so beginners often overlook it. But it is paid on every entry and exit.

That matters most for active traders. Someone scalping for 5-pip gains while paying a 1-pip spread is giving away 20% of their target on costs alone, before any losing trades. The CFTC and FINRA both note that costs and leverage combine to make retail forex a losing game for the majority of participants. The spread is the quieter half of that equation.

How It Works

Spreads come in two main forms and vary with conditions:

• Fixed spreads stay constant under normal conditions but can widen sharply during news or low liquidity.
• Variable (floating) spreads track real market conditions, tightening when liquidity is deep and widening when it thins.

Drivers of spread width:

• Liquidity of the pair. Majors like EUR/USD have the tightest spreads because of enormous turnover (per BIS data). Exotics are far wider.
• Time of day. Spreads narrow during the busy London-New York overlap and widen in the thin hours between sessions.
• Volatility and news. Around central-bank decisions or surprise data, dealers widen spreads to protect themselves, sometimes dramatically.
• Order size. Large orders may not fill entirely at the top of the book, producing slippage on top of the quoted spread.

Some brokers advertise "zero" or "raw" spreads but charge a separate commission instead, the cost is just relocated, not removed.

Worked Example

You trade one standard lot (100,000 units) of EUR/USD. The dollar is the quote currency, so each pip is about $10.

The quote is 1.10000 / 1.10010, a 1-pip spread. The moment you buy at 1.10010, your position is marked at the bid (1.10000), an immediate paper loss of 1 pip, or $10. To break even, the market must move 1 pip in your favor just to cover the spread.

Now scale the activity. If you make 10 round-trip trades a day at a 1-pip spread on a standard lot, that is $100 a day in spread cost, roughly $2,000 over a 20-day trading month, before a single losing trade. On a volatile exotic where the spread might be 30+ pips, the same activity would be financially impossible. The spread, multiplied by frequency and size, is a structural headwind.

Common Mistakes

1. Ignoring the spread as a cost. Because it is embedded in the price, beginners forget they pay it on every trade. Over many trades it is often the single largest expense.

2. Scalping pairs with wide spreads. Trying to capture a few pips on a pair whose spread is several pips means the cost can exceed the target. Tight-spread majors are essential for short-term styles.

3. Trading in thin hours. Spreads widen between sessions and over weekends. Entering then quietly raises your cost and slippage.

4. Believing "zero spread" is free. Zero-spread accounts typically charge commission. Always total spread plus commission to find the true cost.

5. Overtrading under leverage. High leverage tempts frequent trading, and frequent trading multiplies spread costs. This combination is a major reason most retail accounts lose money.

Frequently Asked Questions

Q: What is the bid-ask spread in forex? It is the difference between the bid (the price you can sell at) and the ask (the price you can buy at). Measured in pips, it represents the main cost of opening and closing a position.

Q: Why do I lose money the instant I open a trade? Because you buy at the ask and the position is valued at the bid. The difference is the spread, so every new trade starts slightly negative by the spread amount until the market moves in your favor.

Q: Why are spreads wider on exotic pairs? Exotics have far lower trading volume than majors, so dealers face more risk providing liquidity and widen the spread to compensate. Lower liquidity also means larger slippage.

Q: When are spreads tightest? During periods of deep liquidity, especially the London-New York session overlap. Spreads widen in quiet hours, over weekends, and around major news releases.

Q: Does a zero-spread account mean free trading? No. Zero- or raw-spread accounts usually charge a separate commission. The total cost is spread plus commission, so the expense is relocated rather than eliminated.

Sources

1. Bank for International Settlements. "Triennial Central Bank Survey of Foreign Exchange." https://www.bis.org/statistics/rpfx22.htm
2. Investor.gov. "Foreign Currency Trading (Forex)." https://www.investor.gov/introduction-investing/investing-basics/glossary/forex
3. CFTC. "Forex Trading." https://www.cftc.gov/LearnAndProtect/AdvisoriesAndArticles/forex_trading.html
4. FINRA. "Forex (Foreign Currency) Trading." https://www.finra.org/investors/insights/forex
5. European Central Bank. "Euro Foreign Exchange Reference Rates." https://www.ecb.europa.eu/stats/policy_and_exchange_rates/euro_reference_exchange_rates/html/index.en.html

Disclaimer

This article is educational content only and is not financial advice. Nothing here is a recommendation to buy, sell, or hold any security. Consult a licensed advisor before making investment decisions.