Defined-Risk 0DTE Trades - Credit Spreads and Iron Condors
Reviewed by Leon Moyer - Published October 9, 2026 - Last reviewed October 9, 2026
In this lesson
Calculate the maximum profit, maximum loss and break-evens of a same-day credit spread and iron condor, and explain why a defined risk can still be large relative to the credit.
A defined-risk 0DTE trade is a same-day options position whose maximum loss is fixed the moment you open it, usually because every option you sell is paired with one you buy further out. The two most common are the credit spread and the iron condor, both of which collect premium that decays to zero by the close if the market stays away from the short strikes.
Defined risk is not the same as small risk. The first example below risks more than eleven times what it can earn.
Defined risk can still be a large loss. A same-day credit spread often risks many times the credit it collects: about 11 times and 5 times in this lesson's two examples. A sharp move into the close can take it from full profit to maximum loss in minutes. Size each trade so the maximum loss, (width - credit) x 100, is an amount you can afford to lose. Without its long leg, a short option is not defined-risk at all: an uncovered short put can lose up to the strike x 100 minus the premium ($596,870 for the 5970 put below, if SPX fell to zero), and an uncovered short call has no limit.
What is a 0DTE credit spread?
A credit spread sells one option and buys another of the same type and expiration, further out of the money. You receive more for the option you sell than you pay for the one you buy, so you collect a net credit. A bull put spread (put credit spread) uses puts below the market and profits if the underlying stays up; a bear call spread uses calls above the market and profits if it stays down.
The long option is what defines the risk. Below its strike, every point the short put loses is offset by a point the long put gains.
Worked example
0DTE credit spread example: SPX 5970/5960 put spread
Hypothetical prices. SPX is at 6,000 on the morning of a daily expiration, with 6.5 hours to the close. You sell the 5970 put for $1.30 and buy the 5960 put for $0.50, for a net credit of $0.80. SPX options are worth $100 per index point, so you collect $80.
- Maximum profit: the $80 credit, if SPX settles at or above 5,970.
- Maximum loss: (10-point width - $0.80 credit) x 100 = $920, if SPX settles at or below 5,960.
- Break-even: 5,970 - 0.80 = 5,969.20.
The trade wins if SPX finishes no more than 30 points (0.5%) lower. It risks $920 to make $80.
Illustrative and hypothetical. The ticker and prices are invented for teaching, and the figures exclude commissions, fees, margin interest and taxes, which reduce real results. Past or hypothetical outcomes do not indicate future results.
Same-day SPX 5970/5960 put spread for a $0.80 credit
Hover or tap the chart, or focus it and use the arrow keys, to read any price.
Open this trade in the free calculatorShow as table
These premiums are what the Black-Scholes model gives at 15% implied volatility, rounded to the $0.05 tick. Real same-day puts below the market usually cost more than the model's flat-volatility price because of volatility skew, so real credits for this spread could be larger.
Why buy the long put at all?
Because the short put alone has a much larger risk. Selling the 5970 put by itself collects $130 instead of $80, but its loss keeps growing as SPX falls.
What the long put is for: SPX falls 60 points into the close
Loss per contract with SPX at 5,940
With SPX settling at 5,940, the naked short put loses $2,870 while the spread loses its $920 maximum. At 5,900, the naked put loses $6,870 and the spread still loses $920. The $50 paid for the long put buys a floor under the loss.
How does a 0DTE iron condor work?
An iron condor combines a put credit spread below the market with a call credit spread above it. It collects two credits and keeps them both if the underlying settles between the two short strikes. Only one side can lose at expiration, so the maximum loss is the width of one spread minus the total credit.
Worked example
0DTE iron condor example: SPX 5960/5970/6030/6040
Hypothetical prices, SPX at 6,000. Add a call spread to the put spread above: sell the 6030 call for $1.35 and buy the 6040 call for $0.55, another $0.80 credit. The total credit is $1.60, or $160.
- Maximum profit: $160, if SPX settles between 5,970 and 6,030.
- Maximum loss: (10 - 1.60) x 100 = $840, if SPX settles at or below 5,960 or at or above 6,040.
- Break-evens: 5,970 - 1.60 = 5,968.40 and 6,030 + 1.60 = 6,031.60.
Adding the second spread raised the credit and the break-even cushion on the put side, and lowered the maximum loss, but it added a second way to lose: a rally of more than 30 points now hurts too.
Illustrative and hypothetical. The ticker and prices are invented for teaching, and the figures exclude commissions, fees, margin interest and taxes, which reduce real results. Past or hypothetical outcomes do not indicate future results.
Same-day SPX iron condor for a $1.60 credit
Hover or tap the chart, or focus it and use the arrow keys, to read any price.
Open this trade in the free calculatorShow as table
What risks remain in a defined-risk 0DTE trade?
- Gamma near the short strike. As Gamma and Theta on Expiration Day showed, a short option's delta flips fastest when the underlying is at its strike in the final hours. A spread that looked safe at 2 p.m. can be at maximum loss by 3:30.
- Getting out costs money. Closing four legs means crossing four bid-ask spreads. Many traders close early rather than hold every trade to settlement.
- Settlement style. The SPX examples are cash-settled and European-style, so there are no shares and no early assignment. The same structure on a share-settled ETF such as SPY can be assigned, and a short leg that finishes just in the money can leave you holding shares overnight. 0DTE Expiration and Assignment covers this.
- Repeated small wins, occasional large losses. One maximum loss on the condor ($840) erases more than five full wins ($160 each).
What about debit spreads?
A debit spread is the buyer's version: buy an option near the money and sell one further out. You pay a net debit, which is the maximum loss, and the maximum profit is the width minus the debit. On a same-day trade it caps both cost and payoff, and it still goes to zero if the underlying does not move far enough by the close.
Check your understanding
You sell a 0DTE SPX 6030/6040 call spread for $0.80. What are its maximum profit, maximum loss and break-even?
Show answer
Maximum profit is $80, if SPX settles at or below 6,030. Maximum loss is (10 - 0.80) x 100 = $920, at or above 6,040. Break-even is 6,030 + 0.80 = 6,030.80.
The iron condor in this lesson collected $1.60. What is its profit or loss if SPX settles at 6,035?
Show answer
A loss of $340. The 6030 call is worth 5 points ($500) against the position and the 6040 call expires worthless, so the result is $160 - $500 = -$340.
Why is a 0DTE credit spread called defined-risk, and why is that not the same as low-risk?
Show answer
Its maximum loss is fixed at the width minus the credit as soon as it is opened. But that maximum is often many times the credit, and on expiration day it can be reached very quickly.
Key takeaways
- A credit spread sells one option and buys a further out-of-the-money one; the long leg sets the maximum loss.
- Credit spread maximum loss = (width - credit) x 100; break-even = short strike minus the credit for puts, plus the credit for calls.
- An iron condor pairs a put spread and a call spread; only one side can lose at expiration.
- Same-day credit spreads often risk many times the credit, and gamma can move them to maximum loss fast.
Common questions
What is a 0DTE iron condor?
An iron condor opened on its expiration day: a short put spread below the market and a short call spread above it. It collects a credit and keeps all of it if the underlying settles between the two short strikes. Its maximum loss is the width of one spread minus the credit.
Are 0DTE credit spreads safe?
They are defined-risk, not low-risk. The most a credit spread can lose is fixed when you open it, but that maximum is often many times the credit collected, and on expiration day the market can travel from a winning price to the maximum loss within an hour.
Why trade 0DTE spreads on SPX instead of SPY?
SPX options are cash-settled and European-style, so there is no early assignment and no shares are delivered at expiration. SPY options are American-style and settle in shares, which brings assignment risk on short legs. At recent index and ETF prices, an SPX contract is also roughly ten times larger in notional size.
Can a 0DTE credit spread lose more than its max loss?
On a cash-settled index spread held to expiration, the loss at settlement is limited to the width minus the credit, plus fees. On share-settled options, assignment of a short leg near the close can leave you holding shares overnight, and that position can lose more than the spread's maximum.