RUT gamma exposure: flip, call wall, put wall

Dealer gamma by strike for Russell 2000 index, from the option chain itself: two books, the level where net gamma changes sign, and the two strikes that carry the most. Expiries out to 45 days.

data as of 2026-09-18 16:59:55 ET · not updating right now
Spot
2861
from put-call parity
Zero gamma flip
2878
0.6% above spot
Call wall
2855
0.2% below spot
Put wall
2760
3.5% below spot
Net gamma, volume
-$251M
per 1% move
Net gamma, OI
-$3.61B
per 1% move
Price sits below the flip at 2878: on this book dealer hedging adds to a move rather than leaning against it.
Gamma by strike, two books on one axis
OPEN INTEREST · last close
STRIKE
VOLUME · today
2935
2930
2925
2920
2915
2910
2905
2900
2895
2890
2885
2880
2875
2870
2865
2860
spot
2855
call wall
2850
2845
2840
2835
2830
2825
2820
2815
2810
2805
2800
2795
2790
2785
By expiry, volume book
expiryflipcallputnet
2026-09-21285928802860+$9M
2026-09-22285228902815+$10M
2026-09-23291929002880-$19M
2026-09-24286429152785-$3M
2026-09-25285828552850+$10M
2026-09-28293129002835-$20M
How far to trust this bookB

an index or an ETF; the convention holds, the tape is thinner.

Prints a second, regular session0.85
Strikes where the two books agree on the sign63%
Contracts traded today, expiries shown81,275

What this page assumes

  • Calls count as dealer-long gamma and puts as dealer-short. That is a convention, not a measurement: open interest does not say who holds a contract.
  • The volume book signs today's traded contracts. The open-interest book uses positions as of the last close and does not move inside the day.
  • Spot is derived from the option quotes by put-call parity, so it can sit a few cents from the last trade in the underlying.
  • Two roots of the index, the daily and the monthly, are added together on the dates they share.
  • Every figure is dollars of dealer delta per 1% move in RUT, the unit that compares across symbols.
  • There is no tape-signed book on this page. That book exists only where a live engine runs.

Questions

What does it mean that RUT is below its flip?

Net dealer gamma on this book is negative, so hedging flows tend to add to a move. It says nothing about direction.

Why are there two books?

Open interest is positioning as it stood at the last close. Volume is what traded today. When they disagree, that split is the reading.

Is this a trading signal?

No. We tested wall touches and flip crosses on SPX across more than a thousand sessions and found no edge that survives costs. These are measurements of where hedging concentrates.

How is this different from the SPX terminal?

SPX runs on a live engine: every second, with a third book signed print by print from the trade tape. This page is rebuilt from chain snapshots and carries the two conventional books only.