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Sunday, May 31, 2026
Strategy research · full-period backtest

Multiple Entry Iron Butterfly

Six tranches per session. Each tranche sells an ATM body (call + put at the strike nearest spot) with protective wings $25 out, and manages each wing to a stop on the spread mark at the entry credit. Settled same day; no overnight risk. Figures below use the realistic central case of $0.50/contract stop slippage across 11,652 side-trades — read the slippage table before anything else.

Headline · Jun 2022 – Apr 2026 · $0.50 slippage
Total P/L
+$269,885
11,652 sides
Win rate
56.8%
best $1,262 · worst $-1,558
Max drawdown
−$20,805
11% of peak
Peak P/L
+$271,377
Apr 29 2026 · now −$1,492
Slippage sensitivity · read this first
Stop slippage / contractTotal P/LMax drawdownScenario
$0.25+$379,410−$18,955best case · excellent fills
$0.50+$269,885−$20,805realistic central case
$1.00+$50,835−$45,652stress · poor fills on fast tape

A butterfly is stopped on an at-the-money short, and stops fire exactly when the tape is moving — the worst moment for fills. The entire edge therefore lives in the gap between your fill quality and a dollar of slip: the four-year total falls from +$379k at $0.25 to +$51k at $1.00, where the max drawdown (−$46k) nearly equals the whole profit. The featured page uses $0.50. Before sizing up, measure your own buy-back fills against the mid at trigger time — that number, not this page, decides the strategy.

Cumulative P/L · 1 contract · $0.50 slippage
46 monthly anchor points from the real CSV. Peak +$271,377 on Apr 29 2026. Note the choppy ride — 528 losing days vs 448 winning days, with a 77-trading-day stretch underwater in early 2024.
Year-by-year · $0.50 slippage
YearP/LWin rateSides
2022 (Jun–Dec)+$35,54855.8%1,737
2023+$56,72657.0%2,947
2024+$81,01357.1%3,008
2025+$83,60356.9%2,980
2026 (Jan–Apr)+$12,99356.4%980
Total+$269,88556.8%11,652
Directional skew · call vs put side
Put-side P/L
+$224,111
83% of all profit
Call-side P/L
+$45,773
17% of all profit

Managing each wing with its own stop turns a structurally neutral butterfly into a directional bet. In a rising market the call wing is the one that keeps getting tested and stopped, while the put wing rides to expiry collecting full credit — so 83% of the profit came from the short-put side. The 2022–2026 sample was a strong bull market; this is partly a bull-market tailwind, not a market-neutral premium harvest. In a sustained downtrend that engine runs in reverse. Size and risk accordingly.

Streaks & extremes
Longest win streak
9 days
+$13,649 · Oct 24 – Nov 5 2024
Longest losing streak
9 days
−$10,222 · Sep 13 – Sep 23 2022
Longest drawdown
77 days
−$15,499 · Dec 20 2023 – Apr 11 2024
Winning vs losing days
448 / 528
green days are bigger · Sharpe 1.79

The strategy posts more losing days than winning days yet finishes well positive — the green days are simply larger. That fits the butterfly's shape: a quiet pin day lets several tranches survive near the body, while a trend day stops the tested wing across every tranche and stacks a big red day. The worst stretch was a nine-day skid in the September 2022 selloff (−$10,222); the best a nine-day run in late 2024 (+$13,649). Expect a choppy equity curve, not a smooth one.

Winning streak · Oct 24 – Nov 5 2024 · 9 days · +$13,649
DateP/L (all sides)
Oct 24 Thu+$130
Oct 25 Fri+$868
Oct 28 Mon+$4,975
Oct 29 Tue+$21
Oct 30 Wed+$148
Oct 31 Thu+$973
Nov 1 Fri+$1,248
Nov 4 Mon+$1,819
Nov 5 Tue+$3,468
Losing streak · Sep 13 – Sep 23 2022 · 9 days · −$10,222
DateP/L (all sides)
Sep 13 Tue−$289
Sep 14 Wed−$445
Sep 15 Thu−$1,632
Sep 16 Fri−$359
Sep 19 Mon−$1,847
Sep 20 Tue−$1,119
Sep 21 Wed−$812
Sep 22 Thu−$1,054
Sep 23 Fri−$2,664
Locked configuration
Structure
Iron Butterfly (ATM body)
Spread width
$25
Stop multiple
1× (on spread mark)
Min wing credit
$2.00
Slippage per contract
$0.50
Vol filter
none
Tranche entry times (ET)
12:30 · 13:00 · 13:30 · 14:00 · 14:30 · 15:00
Verdict
PAPER FIRSTProfitable every year — but the edge is an execution bet
  • Win rate is stable (55.8% – 57.1%) and every full year is positive at $0.50 slippage. The structure works across the regimes in the sample.
  • The result is highly slippage-sensitive: +$379k at $0.25 → +$270k at $0.50 → +$51k at $1.00. Because stops fire on ATM shorts during fast tape, profitability hinges on your real buy-back fills.
  • The profit is directionally skewed 83% comes from the short-put side in a four-year bull market. A sustained downtrend reverses that engine.
  • The ride is choppy: more losing days (528) than winning days (448), a 77-trading-day drawdown in early 2024, and a −$20.8k worst peak-to-trough. Profit comes from green days being larger, not more frequent.
  • Verify your own stop fills before going live, and keep the monitor loop healthy — the butterfly rests no broker stop, so its protection is the bot's synthetic spread-mark stop. Not financial advice.
Methodology · short version
  • Data: SPX 0 DTE option chains snapshot at each tranche entry time, with 1-minute resolution for the spread-mark stop checks.
  • Structure: iron butterfly — both shorts pinned to the ATM body, wings $25 out. Each wing managed independently; stop on the spread mark (short − long) at 2× the entry credit (stop_multiple 1.0).
  • Stop fills modeled at ask on the short and mid on the long, plus a flat slippage charge per stop. The featured page uses $0.50/contract; defined-risk close cost is capped at the spread width so blown-out quotes on violent days can't book an impossible loss.
  • End-of-day positions settled at intrinsic value. For trade-by-trade detail, run meib_backtest.py on the VPS — it writes a full CSV with entry, exit, and P/L per wing.

Numbers regenerated 31 May 2026 from meib_full.csv ($0.50 slippage) on the VPS. Rerun the backtester monthly — and re-check the slippage band — to keep this page current.