Costco's Executive Penetration Could Unlock More Earnings

Costco grew total paid memberships 4.1% Y/Y to 82.9M in Q3 FY2026, while executive memberships rose faster at 9.6% to 41.2M, with executive members driving 75% of worldwide sales. Membership fee income increased 10.7% Y/Y to $1,373M, and even excluding the September 2024 fee hike and FX, membership income still grew 7% on premium upgrades, supported by benefits like longer warehouse hours and Instacart incentives. The article notes Costco shares are down 5% over three months and that the stock trades at 42.84x forward P/E vs. 30.91x for the industry, while consensus implies +9.4% sales and +13.3% EPS growth for the current fiscal year.

Analysis

The real lever here is not membership count, it is monetization per member. Premium-tier penetration changes the earnings quality mix by raising recurring fee revenue and improving visit frequency, which tends to lift inventory turns, private-label mix, and vendor bargaining power over time. That makes the model structurally more resilient than a typical retailer when discretionary demand softens.

Near term, though, the market may be paying too much for a story that is already well understood. At ~43x forward earnings, COST needs continued acceleration in executive mix and renewals just to hold the multiple; any slowdown in upgrades or softer traffic would hit the stock through valuation before it shows up in reported EPS. The incremental perks used to drive adoption are also a watch item because they can compress merchandise margin or SG&A leverage even as fee income rises.

Relative winners are the members-first peers: WMT and BJ can keep monetizing loyalty programs, but COST’s stronger execution forces them to spend more on benefits, convenience, and retention to avoid share loss. The contrarian point is that consensus may be underweighting how durable this moat is over 6-18 months, but over the next 1-3 months the trade is mostly about whether the next data point confirms that fee growth is converting into EBIT, not just top-line optics.

Key Decisions for Investors

• Do not chase COST at current levels; use a pullback or post-earnings volatility to add only if executive-membership growth stays above total paid-member growth by a meaningful margin. Falsifier: fee-income growth decelerates to low-single digits ex-price increase.
• Relative-value trade: long WMT / short COST for 3-6 months. Thesis: WMT’s membership economics are still underappreciated and the stock offers similar loyalty-driven upside at a much less demanding multiple; risk is COST continues to re-rate on continued mix improvement.
• Watch BJ as the highest-beta sympathy beneficiary in the club channel. If BJ’s next print shows higher-tier mix inflecting, it can outperform COST on valuation, but it is not yet a clean outright long without confirmation.
• Set an alert on COST if the forward P/E expands back toward the prior 12-month median while earnings revisions stop rising; that combination would suggest the market is overpaying for already-visible membership strength.