Walmart fell 7.3%. Target fell 7.4%. Both exceeded their expected moves and rattled retail sector sentiment. Now Costco reports Q3 FY2026 results on May 28, 2026, after market close, and options traders are asking the right question: is COST just another retailer about to disappoint, or is its membership model a genuine cushion?
Here is how to read the setup, calculate the expected move, and think through strategy selection before the report.
- Costco (COST) reports Q3 FY2026 on May 28, 2026 after market close (AMC).
- COST historically tends to move less than the IV-implied expected move at earnings: the IV crush pattern has favored premium sellers in most recent quarters.
- The WMT/TGT retail sector fears may inflate COST’s pre-earnings IV above what its own fundamentals justify, creating a potential premium-selling opportunity.
- The ATM straddle price at open on earnings day gives you the market’s expected move in both directions. Calculate it yourself before trading.
- All examples below are hypothetical and illustrative, not trade recommendations.
Why COST Is a Different Earnings Story
Walmart and Target both missed on guidance last week, not on revenue or earnings per share. Their stock drops were driven by forward-looking concerns: fuel cost headwinds (WMT) and consumer discretionary pressure (TGT). Both names moved roughly 7% in either direction, well beyond their expected moves of around 4%.
Costco’s business model is structurally different. The majority of Costco’s operating income comes from membership fees, not retail margins. When same-store sales disappoint, the membership line provides a floor. The question for Q3 FY2026 is whether COST faces the same macro headwinds or whether the membership model insulates it from the consumer discretionary weakness that hurt TGT.
Historically, COST has been one of the more “boring” earnings plays in the consumer staples universe. Its stock tends to move 2-5% post-earnings, and IV often prices in a larger move than actually occurs. That pattern makes COST a recurring favorite for premium sellers around earnings.
How to Calculate the Expected Move
Before entering any earnings trade on COST, calculate the options market’s implied expected move. The simplest method uses the ATM straddle.
On the trading day before earnings (or at the open on earnings day), find the at-the-money call and put with the expiration just after the earnings date. Add their midpoint prices together. That sum represents the market’s expected one-standard-deviation move in either direction.
As a hypothetical illustration: if COST is trading at $900 per share and the ATM 900-strike call and put (expiring Friday after earnings) are each priced at approximately $18, the expected move is roughly $36, or about 4% in either direction. If COST closes above $936 or below $864 after earnings, the actual move exceeded the expected move. These are illustrative numbers only; actual premiums will reflect current IV and conditions.
Compare that expected move percentage to COST’s historical earnings reactions. If historical moves cluster around 2-3% but the market is implying 5%, premium sellers may have an edge. If historical moves match or exceed the implied move, premium-buying strategies become more attractive.
Key Metrics to Watch in the Q3 Report
For options traders, the numbers that matter most are the ones that move the stock, not just headline EPS. For COST, watch these specifically:
- Membership renewal rate: This is the health metric for Costco’s model. A renewal rate above 90% (US/Canada) indicates the membership moat is intact. A decline here would be a structural concern, not just a one-quarter miss.
- Comparable warehouse sales (comp sales): US comps ex-gasoline and ex-FX strip out the noise and show underlying demand. A comp above or below consensus expectations is the most likely driver of a post-earnings gap.
- E-commerce growth: COST has been expanding online. A deceleration here against an accelerating WMT.com would create a narrative gap that the market may price in.
- Guidance language on margins: This is what killed WMT and TGT last week. Watch for any commentary on shrinkage, labor costs, or import tariff exposure.
Options Strategy Frameworks for COST Earnings
There is no universally correct options strategy for an earnings play. The right choice depends on your directional view, IV environment, and risk tolerance. Here are three frameworks:
| Strategy | When It Makes Sense for COST | Primary Risk |
|---|---|---|
| Iron Condor | When IV is elevated vs. COST’s historical move; when WMT/TGT sector fears have inflated COST premiums beyond what its fundamentals justify. Target strikes beyond the expected move range. | COST follows the retail sector selloff and moves more than 5-7%; defined loss on both wings. |
| Short Strangle / Short Straddle | When IV is very high and you want maximum premium capture; undefined risk, requires sufficient account size and approval level. | Large gap in either direction; unlimited theoretical risk on the call side if COST surges on a blowout beat. |
| Long Straddle / Strangle | When you believe COST will follow the retail sector trend and move more than IV implies; when the WMT/TGT pattern suggests retail guidance risk is underpriced in COST. | IV crush after earnings eats into premium even if the stock moves as expected; requires a move larger than the IV-implied range to profit. |
For most retail options traders, the defined-risk approaches (iron condor or long strangle) are more appropriate than undefined-risk short strangles or straddles. The iron condor is particularly suited to COST’s historical pattern of muted reactions.
A Hypothetical Iron Condor Setup
To illustrate the mechanics without making a specific recommendation, here is how a hypothetical iron condor on COST might be structured around earnings. These numbers are illustrative and should not be treated as advice.
Assume COST is trading at $900 and the ATM straddle implies a $40 move (roughly 4.4%). A hypothetical iron condor might sell a call spread with strikes above the expected move (for example, a 960/970 call spread) and a put spread below it (for example, a 860/850 put spread), collecting a combined credit. The maximum loss is the width of either spread minus the credit received. The maximum profit occurs if COST closes between the two short strikes at expiration.
The key question before entering any such trade: does the credit collected justify the risk of COST breaking out of the expected range? If the WMT/TGT retail narrative pushes COST’s actual move beyond 5-6%, the iron condor loses. If COST reports in-line and IV crushes as expected, it profits.
Not every trader should trade earnings. If you are not comfortable with the binary risk around a scheduled event, sitting out is a valid strategy.
The Retail Sector Overhang: Risk Factor
Last week’s WMT and TGT results introduced a narrative risk that was not present before their reports. Both companies mentioned fuel cost headwinds and consumer trade-down behavior. If the COST report surfaces similar language on margins or guidance, the market may reprice COST sharply regardless of headline EPS.
The membership model does reduce COST’s exposure to consumer discretionary pressure, but it does not eliminate macro risk entirely. COST’s guidance language on tariff exposure, import costs, and consumer spending trends will carry more weight than usual given the retail sector context.
Bottom Line
COST’s membership model makes it structurally different from WMT and TGT, and its historical earnings move tends to be smaller than what IV implies. That pattern has historically favored premium sellers. Whether the retail sector overhang from WMT and TGT inflates COST’s pre-earnings IV enough to create a real edge is the key question to answer by looking at the actual straddle pricing before you trade. Calculate the expected move, compare it to COST’s historical reactions, and size accordingly.
FAQ
Q: When does Costco report Q3 FY2026 earnings?
A: Costco reports Q3 FY2026 results on May 28, 2026, after market close (AMC). Options expiring the same week will capture the earnings move.
Q: How do I calculate the expected move for COST earnings?
A: Find the at-the-money call and put for the expiration just after earnings. Add their midpoint prices together. That total is the market’s expected move in either direction. Compare it to COST’s historical post-earnings moves to see whether IV is elevated or suppressed.
Q: Is COST more or less likely to have a big earnings move than WMT or TGT?
A: Historically, COST tends to move less than WMT or TGT at earnings because its membership fee income provides more stable operating results. However, the retail sector context from WMT and TGT’s reports this week means COST’s actual move could be larger than usual if guidance disappoints.
Q: Which broker is best for trading options around COST earnings?
A: For earnings options plays, you want a broker with fast execution, competitive commissions, and support for multi-leg spread orders in a single ticket. tastytrade is built for this kind of premium selling workflow, with a flat $1.00/contract open, $0 to close, and a $10/leg cap. Interactive Brokers offers tiered pricing and the deepest options routing for active traders who want the best fills. Commission data verified as of March 2026.
Q: Should I trade COST options if I’m a beginner?
A: Earnings trades are among the riskiest options plays because of the binary, gap-risk nature of the event. If you are new to options, understanding the strategy mechanics first (iron condors, strangles, IV crush) before applying them to a live earnings event is the better approach. The COST setup is educational regardless of whether you trade it.