Two numbers every iron condor trader repeats
Ask anyone who sells premium the tastytrade way how long they hold an iron condor and the answer comes back as a pair: enter around 45 days to expiration, start managing at 21. The pair is repeated so often that the reasoning behind it gets lost. The reasoning matters, because it explains both why the numbers work and why they are only a band, not a law.
Theta and gamma move in opposite directions
An option has a clock inside it. Theta is the amount of value it loses each day from time alone. A seller wants theta: every quiet day, the condor gets cheaper to buy back.
Gamma is the other side of the same clock. It measures how fast delta changes when the underlying moves. A short strike with low gamma barely notices a normal day’s move. A short strike with high gamma can go from a comfortable 20 delta to a tested 45 delta on one ordinary session.
Both Greeks are small far from expiration and both grow as expiration approaches, but not at the same pace. Theta rises steadily. Gamma rises slowly, then steeply in the last three weeks. Days to expiration is the dial that sets both at once, which is why the calendar matters more to a condor’s behavior than the stock price does on most days.
Why enter around 45 days
The 45 DTE entry for an iron condor sits where the tradeoff favors the seller. The credit is large enough to cover four commissions and justify the buying power the condor ties up. The daily decay is already meaningful. Gamma is still low, so the underlying can wander around inside the short strikes for weeks without forcing a decision.
A condor opened ten days out pays more per day but offers no room to be wrong. A condor opened 90 days out ties up capital for a long time while collecting slow decay and carrying more sensitivity to a change in implied volatility.
ACondor’s mechanical engine does not look for exactly 45. It scans a 30 to 65 day band and prefers standard monthly expirations, which have the open interest and the tighter bid-ask spreads a four-leg order needs. The center of that band is about 45 days. The classic tastytrade window was 30 to 60; the extra five days keep a monthly expiration inside the window for about three weeks of every month instead of ten days.
Why start managing at 21 days
Around three weeks out, the daily decay still looks attractive, but gamma has caught up. The credit left in the position is small compared with how quickly a short strike can now be tested. The last three weeks also hold the expiration-week hazards: pin risk at a strike, early assignment on a short that has gone in the money, and thin, wide quotes on a chain in its final days.
The iron condor 21 days to expiration rule is a line in the calendar that says the trade’s useful life is over, whatever the price did. ACondor treats it as a backstop. If a mechanical condor is still open at 21 DTE, the software closes it, whether it stands at a small loss or has not quite reached its target.
Most condors never reach 21
The backstop rarely fires on a healthy trade, because an earlier rule closes it first. The first exit rule the engine applies is the 50 percent rule: once the condor can be bought back for half the credit collected, it is closed and the capital goes back into the queue for the next entry. In a normal cycle that happens somewhere in the middle of the trade, often before day 21 arrives.
The order of exit rules is fixed and runs on every open position every cycle:
1. Assignment cleanup
If a stock leg has appeared in the account because a short was assigned early, the whole position is closed before anything else is considered.
2. News gate
High-confidence opposing news closes the position. Lower-confidence opposing news reduces it by half.
3. The 50 percent rule
Close when the position can be bought back for half the credit received.
4. Delta defense
A short strike at 0.45 delta or beyond, or an underlying that has moved more than 1.5 times the implied move at entry, engages the roll ladder.
5. The 21 DTE backstop
Close whatever is left.
21 days is where a tested condor gets a decision
Delta defense and the 21 day rule are connected. A tested condor with more than 21 days left and no abnormal move is defended, not dumped: the tested side can be rolled further out of the money for a credit, or the position is simply held, because time and credit are what make a defined-risk trade recoverable. Closing a condor on delta alone with plenty of time left turns a recoverable position into a realized loss.
Once the calendar reaches 21 days, that patience runs out. A tested side can be rolled out to the next monthly cycle, back to roughly 45 days, but only when the roll pays a net credit after the broker’s own fee calculation for every leg. A roll that does not pay is refused and the position is closed. ACondor never pays a debit to extend a losing side.
What the software adds to a rule anyone could follow
Nothing about 45 to 21 is a secret. The difficulty is applying it the same way on every trade, on the Tuesday a stock gaps, on the Friday before a holiday, in the month when the trader is traveling. ACondor stores every threshold as a configuration value: the 30 to 65 day entry band, the 20 delta short strikes, the 10 point wings, the 50 percent close, the 0.45 delta defense trigger, and the 21 day backstop. The position table shows days to expiration and the rule currently governing each open trade. The decision about each condor is made once, in the settings, rather than once per trade at the screen.
The limits of the rule
A rule that closes at 21 days limits exposure to the final weeks of a contract. It does not prevent losses before then, and no entry window turns a condor into a position that cannot lose. Selling premium relies on implied volatility overstating the move that happens, which is a tendency, not a certainty.
ACondor is software, not investment advice. Nothing here is a guarantee of any trading result, and options trading carries substantial risk of loss.
To run the 45 to 21 cycle as fixed rules on a tastytrade account, request early access.
ACondor LLC
+1 575 312 9326
2521 North Main Street, Las Cruces
Unit 1-276
Las Cruces
New Mexico
88001
United States
