IV rank as an entry filter, wing width and margin

The condor's credit is set by implied volatility, and IV is not a constant. The same strikes collect three times as much when IV is 45% as when it is 20%, which is why systematic sellers filter entries by IV rank before they look at anything else. This lesson covers that filter, then the two decisions that set the dollar risk: wing width and the margin it requires.

IV rank and IV percentile

IV rank = (current IV − 52-week low IV) ÷ (52-week high IV − 52-week low IV). XYZ's IV is 30%; over the past year it has ranged from 18% to 48%. IV rank = (30 − 18) ÷ (48 − 18) = 40%.

IV percentile is the share of days in the past year on which IV was below today's level. The two can disagree: a single spike to 48% pulls the rank down for a year, while the percentile ignores how extreme the spike was.

Sellers typically require IV rank above 30–50 before opening a condor. Two reasons:

1. The credit scales with IV. Fix the strikes from the previous lesson (44/39 – 56/61, 45 days) and vary IV:

At IV 20% the same condor collects $22 and risks $478. You could instead move the strikes in to keep 16 delta (about 46/41 – 54/59), which restores the credit to around $0.75 but shrinks the profit range to $8 wide instead of $12. Either way, low IV means a poor ratio or a narrow range. There is no third option.

2. High IV tends to fall. IV is mean-reverting: after a spike, it usually declines toward its average as the fear passes, and a short-vega position gains from that decline on top of theta. That is the volatility risk premium at work.

Two cautions belong next to the rule. First, IV rank is high for a reason: earnings in the window, a pending court ruling, a sector sell-off. Check why before you sell it, because a condor through an earnings report is a different trade from a condor in a quiet month. Second, mean reversion is a tendency with no schedule. In the spring of 2020 broad-market IV rank sat at 100 for weeks while IV itself kept rising; "high IV rank" was true every day on the way from 30 to 80.

Wing width

Keep the short strikes at 44 and 56 and vary the wings:

The pattern is the one from Module 2. Narrow wings have the best ratio, the most friction per dollar collected, and the smallest risk per contract; wide wings approach the strangle. Choose the width by dividing the loss you will accept per position by the number of contracts you intend to trade. A trader with a $1,000 per-position limit who wants to trade two condors needs a max loss under $500 each: the $5-wide fits, the $10-wide does not.

Two further points on wings:

• Wings are protection against gaps, not against normal moves. Between $44 and $39 the $5-wide condor loses exactly as much as the strangle. The wing only earns its $27 when the stock is past it, which is precisely the scenario you cannot manage out of.
• Asymmetric wings are fine. Put skew makes the downside wing more expensive per dollar of width than the upside wing. Some traders use $5 wings on the put side and $3 on the call side, or shift the short call closer, to balance the credit. There is nothing sacred about symmetry.

Loss profile below the short put, $5 vs $10 wings vs strangle

  XYZ at expiry:  44    41    39    36    34    30
  $5-wide         0   -222  -422  -422  -422  -422
  $10-wide        0   -206  -406  -706  -906  -906
  Strangle        0   -195  -395  -695  -895  -1295
                  (per contract, in dollars)

Margin

Under standard Reg-T margin, an iron condor's requirement is the max loss of the wider side: $422 for the $5-wide condor. It does not change when the stock moves, because the loss cannot exceed it.

A strangle's requirement is formula-based and moves. Initially about $545 here. If XYZ falls to $44 and IV rises to 40%, the put side's requirement is roughly 20% of $4,400 plus the put's new premium (now around $1.60), about $1,040, and the position is also showing a loss. Buying power shrinks as the trade goes against you, which is the mechanism behind forced liquidation in a sell-off: the loss and the margin call arrive together. In stressed markets brokers also raise house requirements, so the number can jump for reasons unrelated to your position.

Portfolio margin (Module 7) replaces both with a stress test across price moves, which usually reduces the requirement for hedged positions and is the main reason larger accounts use strangles rather than condors. Until you have it, condors are the version that fits a small account and cannot generate a margin call.

Key idea: Enter condors when IV rank is high enough that the credit is worth the risk, but check why IV is high; a fixed-strike condor collects three times more at IV 45 than at IV 20. Wing width sets the dollar risk per contract and does nothing until the stock is past the wing. Condor margin is fixed at the max loss; strangle margin rises exactly when the trade is losing.

Try it: For a stock you follow, find its current IV, 52-week IV range, and compute IV rank. Then price the same 16-delta condor with $2, $5 and $10 wings and fill in the wing-width table with real numbers, including the credit ÷ width column. Decide which width fits a $1,000 per-position limit at two contracts.

Recap

• IV rank = (IV − 52w low) ÷ (52w high − 52w low); sellers typically want it above 30–50.
• Fixed-strike condor credit roughly triples from IV 20% to IV 45%; low IV means a thin credit or a narrow range.
• High IV has a cause; check it. Mean reversion has no schedule.
• Wing width sets max loss per contract; narrow wings have the best ratio and the most friction, and every wing is idle until the stock is past it.
• Condor margin is fixed at max loss; strangle margin grows with adverse moves and IV, and brokers can raise it further.