Costco's Best Numbers Came With an Asterisk

Costco reported fiscal Q4 adjusted EPS of $6.60, up 12.4% and modestly above the $6.48 consensus, on net sales of $93.9 billion (+11.2%); reported EPS of $6.75 included a nonrecurring $0.15-per-share IEEPA tariff-refund benefit. Comparable sales rose 6.7% excluding gasoline and FX, supported by 3.3% traffic growth, while core merchandise margin expanded 18bps and SG&A improved 27bps. The key concern is membership-fee income growth slowing to 7.3% from roughly 14% a year earlier as the prior fee increase laps, limiting upside for a stock valued near 40x forward earnings despite improving renewal rates and accelerated warehouse expansion.

Analysis

COST faces an earnings-algorithm de-rate rather than a demand problem. With the fee-reset contribution now largely annualized, incremental operating-income growth must come from membership adds, warehouse productivity, and merchandise margin; each is lower-quality or more execution-dependent than a fee uplift. At a premium multiple, even modest FY27 estimate reductions can drive 5-10% downside through multiple compression before fundamentals deteriorate.

The more actionable read-through is relative: sustained value-seeking and Costco’s expanding physical footprint pressure discretionary and home-improvement retailers with weaker traffic economics, particularly HD and TGT. WMT is the closest offsetting beneficiary because its scale and grocery frequency support the same trade-down behavior, but its membership narrative is also vulnerable to eventually lapping promotional or pricing-driven subscriber growth. Retail earnings revisions over the next 1-3 months should normalize tariff-related windfalls out of base margins; companies that did not quantify the benefit cleanly carry the greatest estimate-risk.

Contrarianly, a COST short is not clean. Higher renewal quality, premium-member mix, and new-unit openings can preserve high-single-digit operating-income growth, while a lower stock price may attract long-only buyers seeking defensive consumer exposure. The bearish thesis is falsified if management demonstrates renewed fee-income acceleration through member additions and higher-tier penetration, or if FY27 EPS consensus holds despite removal of the prior fee-reset tailwind.

Key Decisions for Investors

• Maintain COST as underweight versus WMT over a 1-3 month horizon; express through long WMT / short COST in equal dollar amounts after post-earnings liquidity normalizes. Target 8-12% relative downside for COST if FY27 consensus resets; stop if COST’s relative performance exceeds WMT by 7% or management raises FY27 earnings outlook.
• Avoid adding outright COST exposure until analysts complete FY27 revisions and the stock establishes support after the initial reaction. A re-entry requires evidence that new warehouses and premium-member mix offset the lost fee-growth cadence; watch next monthly sales release and first FY27 membership-income growth print.
• Increase scrutiny of TGT, TJX, ANF and HD estimates during upcoming results: normalize reported gross-margin gains for tariff refunds before treating them as recurring. Favor short exposure only where management cannot quantify the one-time benefit and forward margin guidance remains unchanged; this is an estimate-risk screen, not a blanket retail short.
• For defensive retail allocation over 6-12 months, prefer WMT over COST on risk-adjusted valuation sensitivity, while retaining COST only as a watch-list compounder. The key risk to the pair is broad consumer reacceleration that restores discretionary traffic and supports premium-multiple defensives simultaneously.