What does it mean when MFI falls below the 20 oversold zone?

When the Money Flow Index (MFI) drops below 20, it signals oversold conditions and potential exhaustion of selling pressure, but traders should wait for confirmation—like a move back above 20 or bullish divergence—before acting, especially in strong downtrends where MFI can remain low for extended periods.

Jul 25, 2025 at 12:42 pm

Understanding the Money Flow Index (MFI)

The Money Flow Index (MFI) is a technical oscillator that measures the flow of money into and out of an asset over a specified period, typically 14 days. It combines price and volume data to assess buying and selling pressure, making it a valuable tool for traders analyzing potential reversals or continuations in price trends. The MFI ranges from 0 to 100, with levels above 80 considered overbought and levels below 20 classified as oversold. When the MFI falls below the 20 threshold, it signals that the asset may be oversold, indicating a potential exhaustion of selling pressure.

Unlike the Relative Strength Index (RSI), which only uses price, the MFI incorporates volume, giving it an edge in detecting strength or weakness behind price moves. A reading below 20 suggests that buyers are significantly outweighed by sellers, and sustained low volume during price declines can confirm bearish momentum. However, an MFI dropping below 20 does not automatically imply an immediate reversal—it merely highlights that the asset is in extreme territory and warrants further investigation.

Interpreting MFI Below the 20 Level

When the MFI drops below 20, it reflects intense selling activity and potentially oversold conditions. This could mean the asset has been aggressively sold off, possibly beyond its fundamental value. Traders interpret this signal as a warning that downward momentum may be nearing exhaustion. However, the mere crossing of the 20 line does not guarantee a price bottom.

• Price may continue to fall even as MFI is below 20, especially in strong downtrends.
• Divergences between price and MFI are critical: if price makes a new low but MFI forms a higher low, it suggests weakening selling pressure and a potential bullish reversal.
• Volume trends during the drop are essential—declining volume on down moves may indicate lack of conviction among sellers.

It's crucial to avoid assuming a mechanical buy signal simply because MFI enters the oversold zone. Confirmation from price action, candlestick patterns, or additional indicators increases the reliability of the signal.

How to Calculate and Identify MFI Signals

To fully understand when MFI falls below 20, one must know how it's calculated. The process involves multiple steps:

• Calculate Typical Price for each period: (High + Low + Close) / 3
• Multiply Typical Price by Volume to get Raw Money Flow
• Determine Positive and Negative Money Flow: Compare today’s Typical Price to yesterday’s. If higher, it’s positive flow; if lower, it’s negative.
• Sum Positive and Negative Money Flow over the past 14 periods
• Compute Money Ratio: Positive Money Flow / Negative Money Flow
• Calculate MFI: 100 – (100 / (1 + Money Ratio))

Once the MFI value is derived, plot it on a chart. When the line crosses below 20, mark the event and analyze the context. Most trading platforms like TradingView, MetaTrader, or CoinGecko Pro offer built-in MFI indicators, eliminating the need for manual calculation.

Strategic Responses to MFI Below 20

When the MFI dips below 20, traders can consider several tactical responses, depending on their strategy and risk tolerance:

• Wait for confirmation: Look for a move back above 20, which may confirm that buying pressure is returning.
• Check for bullish divergence: If the price records a lower low but MFI forms a higher low, this hidden strength may precede a reversal.
• Monitor volume spikes on up days: A sudden increase in volume during a price bounce can validate accumulation.
• Use support levels: Align the MFI signal with key technical support zones, such as Fibonacci levels or historical demand areas.
• Combine with moving averages: A bounce near a long-term moving average (e.g., 200-day MA) alongside MFI rising from below 20 adds credibility.

Avoid entering long positions immediately after MFI hits 18 or 15. Instead, wait for MFI to turn upward and cross back above 20, which often coincides with a shift in momentum. This approach reduces false signals in prolonged bear markets.

Common Misinterpretations and Risks

A frequent mistake is treating an MFI reading below 20 as a guaranteed buy signal. In strongly trending markets, assets can remain oversold for extended periods. For example, during a sharp crypto sell-off, Bitcoin might have MFI below 20 for several days while the price continues to drop. In such cases, premature entries lead to losses.

Another risk is ignoring the broader market context. If the entire cryptocurrency market is in a downtrend due to macroeconomic factors like rising interest rates or regulatory crackdowns, a single asset’s oversold MFI may not lead to recovery. Always assess:

• Market-wide sentiment
• On-chain data (e.g., exchange outflows, whale movements)
• Funding rates and open interest in futures markets

Moreover, low liquidity assets can produce distorted MFI readings due to erratic volume, making the indicator less reliable. Altcoins with thin trading volumes may show false oversold signals that quickly reverse.

Practical Example: MFI in a Crypto Downturn

Consider Ethereum during a market correction in mid-2022. Over a 14-day period, ETH price declined from $1,800 to $1,300. During this drop:

• The Typical Price decreased each day
• Negative Money Flow dominated as volume spiked on down days
• After 14 periods, the MFI dropped to 18
• Price continued falling to $1,200 over the next week

However, during the second week, MFI began to rise from 18 to 25 while price stabilized near $1,200. This upward turn in MFI, combined with a bullish engulfing candle and decreasing sell volume, signaled a potential reversal. Traders who waited for MFI to reclaim above 20 before entering saw a rebound to $1,600 in the following month.

This example shows that the timing of the exit from the oversold zone matters more than the entry into it.

Frequently Asked Questions

Q: Can MFI stay below 20 for a long time?

Yes. In strong downtrends, especially during bear markets in cryptocurrency, MFI can remain below 20 for days or even weeks. This reflects sustained selling pressure and does not indicate an immediate reversal. The indicator can become "stuck" in oversold territory, so traders should not assume a bounce is imminent.

Q: Is MFI more reliable on higher timeframes?

Generally, yes. On the daily or weekly charts, MFI signals are less noisy and more reliable due to higher volume and reduced short-term volatility. Signals on 1-hour or 15-minute charts may produce frequent false readings, especially in low-cap altcoins.

Q: How does volume affect MFI accuracy?

Volume is central to MFI. If volume is low during a price drop, the resulting MFI decline may not reflect strong conviction. Conversely, high volume on down days that pushes MFI below 20 suggests powerful selling. Always cross-verify volume trends with MFI movements.

Q: Should I use MFI alone or with other indicators?

MFI should not be used in isolation. Combine it with tools like RSI, MACD, or Bollinger Bands, and consider on-chain metrics for crypto assets. For example, a drop below 20 MFI alongside declining exchange reserves may strengthen a bullish reversal hypothesis.