State Street SPDR S&P 500 ETF (SPY) Open Interest History
Open interest tracks the total number of outstanding options contracts. Rising OI alongside price moves can indicate growing commitment to the trend; declining OI suggests positions are being closed.
State Street SPDR S&P 500 ETF (SPY) operates in the Financial Services sector, specifically the Asset Management industry, with a market capitalization near $829.92B, listed on AMEX, carrying a beta of 1.01 to the broader market. SPY is the best-recognized and oldest US listed ETF and typically tops rankings for largest AUM and greatest trading volume. public since 1993-01-22.
Snapshot as of Oct 6, 2026.
- Spot Price
- $779.51
- Call OI
- 5.7M
- Put OI
- 12.4M
- Total OI
- 18.1M
- Put/Call Ratio
- 0.93
As of Oct 6, 2026, State Street SPDR S&P 500 ETF (SPY) has 18.1M total contracts outstanding across all expirations. Put/call OI ratio is 2.18 (put-heavy positioning, often indicating hedging or bearish bias). Open interest reflects accumulated positions from prior sessions; persistent growth indicates sustained directional or hedging interest, while sharp drops typically mean post-expiration clean-up.
How SPY open interest history Data Feeds Strategy Selection
Strategy selection on State Street SPDR S&P 500 ETF options does not derive from any single metric in isolation. The open interest history view above sits inside a broader read: ATM IV currently sits at 12.5% and dealer gamma exposure is positive, so dealer hedging is mechanically mean-reverting. Combine the open interest history data here with the volatility-skew surface, dealer-gamma exposure, max-pain level, and upcoming-events calendar to build a positioning thesis. Risk-defined structures (credit spreads, debit spreads, iron condors) are usually safer than naked positions while the regime is uncertain; the data on this page anchors the inputs but does not by itself constitute a trade thesis.
How to read the SPY open-interest data
The open-interest time-series above tracks the total State Street SPDR S&P 500 ETF options inventory outstanding day by day. OI is a stock measure - the cumulative position count - so trends flag accumulating or distributing positioning. Current put/call ratio is 0.93, roughly balanced. Total call OI of 5.7M versus put OI of 12.4M gives a put/call OI ratio of 2.18 - structurally a slower-moving signal than the volume-based ratio.
SPY flow vs positioning
Volume tells you what flows happened today; OI tells you what positions accumulated. Both can move in opposite directions: rising volume with falling OI means contracts are being closed (covering); rising volume with rising OI means new positions are being opened. The combination matters more than either alone for reading sentiment. Combined with the current positive dealer-gamma regime, large OI clusters tend to act as price magnets through expiration cycles.
Using SPY OI/volume data alongside other surfaces
Per-strike OI is the input to dealer-gamma calculations: strikes with elevated call OI generate gamma walls that dealers must hedge into as spot approaches them. The gamma-exposure page combines this distribution with the dealers' assumed-long-gamma assumption to project hedge flow. Volume cross-checks recent positioning shifts in the chain that haven't yet shown up in cumulative OI. Pair both with the term-structure view on the volatility page to determine whether the activity is concentrated in near-dated event hedging or longer-dated structural positioning. Front-month expiration for SPY sits at 31 days, so near-dated volume currently dominates the flow reading.
Learn how open interest is reported and how to read the data →
Daily open-interest history for SPY options over the last ~25 trading days. Each row reflects the end-of-day total OI summed across all listed strikes and expirations.
Most recent 15 trading days (descending). Older history appears in the chart above.
| Date | Call OI | Put OI | Total OI | P/C OI |
|---|---|---|---|---|
| Oct 6, 2026 | 5.7M | 12.4M | 18.1M | 2.18 |
| Oct 5, 2026 | 5.8M | 11.9M | 17.7M | 2.06 |
| Oct 2, 2026 | 5.7M | 12.0M | 17.7M | 2.10 |
| Oct 1, 2026 | 5.5M | 11.8M | 17.3M | 2.14 |
| Sep 30, 2026 | 5.9M | 13.1M | 19.0M | 2.24 |
| Sep 29, 2026 | 5.7M | 12.8M | 18.5M | 2.26 |
| Sep 28, 2026 | 5.6M | 12.5M | 18.1M | 2.24 |
| Sep 25, 2026 | 5.7M | 12.8M | 18.5M | 2.23 |
| Sep 24, 2026 | 5.6M | 12.5M | 18.1M | 2.24 |
| Sep 23, 2026 | 5.5M | 12.3M | 17.8M | 2.24 |
| Sep 22, 2026 | 5.5M | 12.2M | 17.7M | 2.24 |
| Sep 21, 2026 | 5.2M | 11.8M | 17.0M | 2.28 |
| Sep 18, 2026 | 6.0M | 15.4M | 21.4M | 2.54 |
| Sep 17, 2026 | 6.3M | 15.3M | 21.6M | 2.42 |
| Sep 16, 2026 | 6.0M | 15.0M | 21.0M | 2.49 |
SPY highest open-interest contracts
| Type | Strike | Expiration | Volume | OI | IV | Bid | Ask |
|---|---|---|---|---|---|---|---|
| PUT | $480.00 | Dec 18, 2026 | 45 | 311.4K | 37.2% | $0.31 | $0.32 |
| PUT | $500.00 | Nov 20, 2026 | 103 | 304.2K | 25.0% | $0.14 | $0.15 |
| PUT | $510.00 | Nov 20, 2026 | 10 | 200.3K | 25.0% | $0.15 | $0.16 |
| PUT | $620.00 | Nov 20, 2026 | 284 | 163.8K | 25.0% | $0.55 | $0.56 |
| PUT | $610.00 | Dec 18, 2026 | 15 | 158.2K | 30.6% | $1.16 | $1.17 |
| PUT | $350.00 | Dec 18, 2026 | 0 | 157.9K | 37.3% | $0.07 | $0.08 |
Top 6 contracts from the institutional-grade nightly options scan; ranked by oi within the broader S&P 500/400/600 + ETF universe.
Frequently asked SPY open interest history questions
- What is the current SPY options open interest?
- As of Oct 6, 2026, State Street SPDR S&P 500 ETF (SPY) has 18.1M total contracts outstanding across all listed expirations, split as 5.7M calls and 12.4M puts. Open interest reflects accumulated positions from prior trading sessions; it does not include today's volume until end-of-day reconciliation.
- What is the SPY put/call open interest ratio?
- Put/call OI ratio of 2.18 is put-heavy, often indicating hedging demand or bearish positioning.
- What does SPY open interest tell traders?
- Persistent OI growth indicates sustained directional or hedging interest; sharp drops typically mean post-expiration position cleanup. Heavy OI concentrations at specific strikes act as support and resistance levels because dealer hedging amplifies near those strikes - the gamma profile of the dealer book is concentrated there. Comparing today's volume to standing OI separates opening flow from closing flow.