Bitcoin options traders lean into upside as short-dated calls gain favor

Bitcoin options traders are paying up for the right to profit if prices rise. At the one-week, 25-delta level, demand for calls is now running ahead of demand for puts.

What the options market is signaling

A call option pays off if Bitcoin rises, and a put pays off if it falls.

The “25-delta” label refers to options that sit a moderate distance from the current price. Traders compare the implied volatility of 25-delta calls against 25-delta puts. The gap is called the risk reversal, or skew. When puts cost more, the market is paying for crash protection. When calls cost more, traders are paying for exposure to a rally.

The broader 25-delta skew turned positive on August 20, 2026. That was the first bullish tilt in roughly 12 months.

The numbers behind the shift

By mid-September 2026, calls made up approximately 61.4% of total Bitcoin options open interest, with puts accounting for 38.6%. Data from Derive put call open interest at around 305,530 BTC.

In the 24-hour volume figures around the initial bullish signal, calls led puts.

In late September, a Derivasys snapshot showed the one-week 25-delta risk reversal rising 1.07 vol points to -0.24. That reading moved from clearly favoring downside protection to roughly neutral within a single snapshot.

Further out on the curve, traders have stacked larger call open interest at the $80,000, $85,000, and $100,000 strikes for December expiries.

Spot price, futures, and ETF flows

Bitcoin spot was trading near $78,000 when the skew flipped positive. In the following weeks, spot consolidated in a range of $82,000 to $85,000. By early October, prices hovered between $80,000 and $85,000, supported by strong inflows into Bitcoin ETFs.

Futures open interest reached about $52.6 billion around the time of the skew flip.

What this means for traders and investors

Large open interest at $80,000 and $85,000 sits close to where spot has been trading, which means those levels could attract attention as expiry approaches. When dealers who sold those calls hedge their exposure, their buying and selling around popular strikes can influence short-term price action.

When calls become more expensive relative to puts, buying upside exposure gets pricier, while protection gets relatively cheaper. For holders who want to hedge, a market leaning toward calls can make downside protection more affordable than it was during the long put-heavy stretch.

The Derivasys reading of -0.24 is a reminder that near-term skew was hovering around neutral rather than screaming bullish. With futures open interest at about $52.6 billion, a crowded market can unwind abruptly if macro conditions sour.