Costco's Membership Fee Boost Is About to Run Out

Costco is set to report fiscal Q4 2026 after the Sept. 24 close, with net sales already disclosed at $93.9B, up 11.3% year over year, and EPS needing to exceed the prior-year $5.87 benchmark. Investors will focus on membership-fee growth as the benefit from the September 2024 U.S. and Canada fee increase fades, and on gross margin, where every 10bps move on quarterly sales represents roughly $94M of pre-tax profit. While comparable sales rose 9.4% and U.S. comps increased 10.7%, the article views the roughly 45x earnings valuation as demanding and advises against buying ahead of earnings.

Analysis

COST's setup is asymmetric into earnings: reported sales are already known, leaving the valuation-sensitive variables—merchandise margin, renewal/member growth, and the cadence of fee-income normalization—to determine whether a premium multiple can hold. Once the fee-reset contribution rolls off, sustaining double-digit EPS growth requires either more members, higher renewal/upgrade mix, or margin expansion; the latter conflicts with Costco's price-investment model and tariff-refund pass-through. A modest 10-20bp gross-margin disappointment would have an outsized effect on forward EPS expectations and could trigger multiple compression rather than merely a one-quarter estimate reset.

The second-order issue is competitive: Costco's willingness to recycle tariff recoveries into price reinforces traffic and renewal but raises the promotional bar for BJ's Wholesale (BJ) and Walmart (WMT), especially in consumables. WMT is better positioned to absorb price competition through its higher-margin advertising, marketplace, and membership ecosystem; BJ has greater relative exposure to a value-seeking customer but less scale to fund price gaps. DoorDash's (DASH) incremental Costco availability is strategically more relevant as a convenience-acquisition channel than as a near-term earnings driver, since fulfillment economics and member behavior—not launch volume—will determine whether it expands Costco's addressable wallet without cannibalizing warehouse trips.

Consensus may underappreciate that a clean print may only defer, rather than eliminate, the deceleration debate. Conversely, a margin miss tied to gas, fresh-food mix, or temporary tariff accounting is not automatically structural; the key falsifier for a bearish view is evidence that renewal rates, executive memberships, and ex-fuel gross margin are accelerating simultaneously. The market reaction should be judged against forward EPS revisions and the post-call multiple, not the headline EPS beat.

Key Decisions for Investors

• Avoid adding directional COST exposure before the Sept. 24 release; at a premium earnings multiple, the risk/reward is unfavorable when the principal upside driver is already embedded and the remaining variables are margin-sensitive.
• For a tactical bearish expression, consider a defined-risk COST put spread 1-3 months out only if implied volatility remains below the expected post-earnings move; target a 8-12% downside on gross-margin weakness or softer fee-income cadence, with risk limited to premium paid.
• Use a relative-value basket: long WMT / short COST over 3-6 months if COST's post-earnings commentary confirms slowing fee-income growth without offsetting ex-fuel margin expansion. WMT has more non-merchandise profit pools and should be more resilient in a price-investment cycle; exit if COST shows accelerating renewal/upgrade metrics plus sustained margin improvement.
• Place DASH on a fiscal-2027 watch list rather than buying on the launch. Upgrade only after disclosures show Costco order frequency, contribution margin, and customer-acquisition efficiency are additive; absent those data, the partnership is not a quantifiable earnings catalyst.
• Watch COST's forward EPS revisions and ex-fuel gross margin after the call. A 10bp-plus year-over-year ex-fuel margin decline paired with fee-income growth below the prior quarter would validate the short thesis; stable-to-up margin and improving renewal/Executive mix would invalidate it.