0DTE Options: Zero Days to Expiration Explained

0DTE options, short for "zero days to expiration," are options contracts that expire at the end of the current trading day. Everything that normally unfolds over the weeks of an option's life is compressed into a few hours: the remaining time value drains to zero by the close, the price can swing violently on small moves in the market, and there is no next day to recover from a wrong call.

They grew after exchanges added expirations for every trading day. Cboe reported that 0DTE contracts represented 59% of SPX options volume during 2025 in its January 2026 industry review. Buyers can lose the entire premium within hours, while some short positions can lose much more than the premium received. These contracts require experience and close attention to expiration mechanics.

This guide explains what 0DTE options are, why they took over so much of the options market, how they behave on expiration day, and, most importantly, what can go wrong. It is written to help you understand the headlines, not to encourage you to trade them.

A 0DTE option compresses an option's entire remaining life, and every risk that comes with it, into a single trading session.

What "zero days to expiration" means

DTE stands for days to expiration, the time an options contract has left before it expires. A 45-DTE option expires in 45 days; a 0DTE option expires today, at the end of the current session.

There are two senses of the term, and both matter. Technically, every option becomes a 0DTE option on its final day, whether it was listed six months ago or last week. What changed is that traders no longer have to wait for that day to arrive: exchanges now list index and ETF options that expire every trading day, so there is always a fresh contract in its final hours.

"0DTE trading" means deliberately opening positions in these same-day contracts, buying or selling options whose entire remaining life is measured in hours rather than weeks. If calls, puts, and premium are still new to you, start with options trading for beginners before reading further here.

Why 0DTE options exploded

Cboe listed the first weekly S&P 500 (SPX) options in 2005, expiring on Fridays. Monday and Wednesday expirations arrived in 2016. Then, in 2022, Cboe added Tuesday and Thursday expirations, and from May of that year SPX had a contract expiring on every trading day of the week. Once every day was an expiration day, same-day trading stopped being a Friday-only event.

The growth since has been steep (figures move, so treat these as of 2026):

• Same-day contracts were a small corner of the market as recently as 2020, when they were roughly a sixth of SPX options volume.
• Cboe reported an average 2.3 million SPX 0DTE contracts per day in 2025, representing 59% of total SPX options volume. This is a dated annual statistic, not a fixed share for every trading day.
• Retail traders drove much of the surge, helped by commission-free brokers and mobile apps, and short-dated contracts now make up a large and growing share of the options they trade.

Short remaining maturity can make premiums appear inexpensive, and heavily traded contracts can have tight spreads. Neither is guaranteed, particularly around news or away from actively traded strikes. An option’s expiration also does not necessarily eliminate overnight exposure: exercise or assignment of a physically settled ETF option can create a stock position.

How they work: SPX vs SPY

Most 0DTE activity happens in S&P 500 products, but the two main vehicles work differently, and the difference matters most at expiration.

European-style SPX and XSP options settle in cash without delivery of shares. Settlement timing varies by series: standard SPX contracts can be AM-settled, while SPXW weekly expirations are generally PM-settled. American-style ETF options can create stock positions through exercise or assignment. Broker deadlines and post-close price changes matter, so the closing quote alone may not determine a trader’s final exposure.

The Greeks on expiration day

If you know the option Greeks, 0DTE is those Greeks at maximum intensity.

Theta estimates the effect of time passing while other inputs are held constant. Near expiration, remaining time value can erode quickly, especially near the money, but there is no universal intraday decay curve. Changes in the underlying price and implied volatility can overwhelm the isolated time effect.

Gamma, which measures how fast an option's directional exposure changes, is at its most extreme. Near the strike on expiration day, an option's delta can snap between almost zero and almost one on a small move in the underlying.

In practice, a modest index move can swing an option's price by a large percentage within minutes. The same gamma that produces a sudden windfall produces a sudden wipeout, and on expiration day it is dialed to maximum. That is what makes 0DTE feel like a lottery ticket to buyers and a minefield to sellers.

Scheduled events magnify all of it. Fed announcements, inflation releases, and major earnings land hard in a market where every contract expires the same evening, inflating premiums beforehand and collapsing or exploding them afterward.

Who trades 0DTE, and why

This is descriptive, not an endorsement. Event traders take short-term directional positions around scheduled news, accepting the possibility of a full premium loss. Premium sellers sell 0DTE spreads and iron condors to collect the day's rapid decay, betting the index stays within a range. Hedgers, including institutions, buy same-day protection around specific events and treat the premium as a one-day insurance cost. The common thread is that every one of these participants is making a same-day, high-precision bet, usually while watching the market full-time. That is the honest job description, and it looks nothing like beginner investing.