Is This Costco's Hidden Growth Engine?

Costco is regaining momentum in 2026 after a 5% decline in 2025, supported by continued high sales and comparable sales growth. The company now has 637 U.S. stores, 115 in Canada, 37 in Japan, 29 in the U.K., seven in China, and plans 28 net new stores in 2026, with a long-term target of at least 30 openings annually. International comps rose 13% year over year in fiscal Q2, lifting total comps to 7.4%, underscoring a strong overseas growth runway.

Analysis

The key read-through is that Costco’s growth runway is shifting from a mature U.S. box-expansion story to a higher-velocity international unit economics story. That matters because new-market comps can stay elevated longer when membership is still being monetized and the brand is underpenetrated, which creates a multi-year tailwind for revenue per opening rather than just square-foot growth. The market likely still underestimates how much of the next leg of earnings can come from mix, not just traffic.

A second-order effect is pressure on regional grocers, club peers, and discounters in markets where Costco is scaling. When Costco expands abroad, it tends to normalize a value/quality benchmark that forces local competitors to spend more on price and logistics, which can compress margins even if they hold share. That also benefits upstream suppliers with scale and private-label exposure, but only those able to support cross-border procurement and lower variance fill rates.

The main risk is that the current optimism can fade quickly if international comps mean-revert once the easiest member-acquisition phase ends. The horizon that matters is 6-18 months: near-term sentiment can stay constructive on reported sales, but the stock becomes vulnerable if unit additions accelerate faster than local operating leverage or if foreign exchange turns from a tailwind into a drag. A slower consumer would hurt domestic comps first; a weaker international consumer would matter more for the multiple because the market is already paying for the growth optionality.

Consensus is treating this as a simple quality compounder, but the more interesting debate is whether Costco is re-rating into a global roll-up of membership economics. If that framing takes hold, the upside is not just low-double-digit EPS growth, but a higher terminal multiple supported by steadier international visibility. The flip side is that if investors conclude international growth is merely exporting the same U.S. model with lower ROIC, the stock can de-rate even with good reported sales.

Key Decisions for Investors

• Stay long COST on pullbacks over the next 3-6 months; the risk/reward favors owning the compounding story as international openings extend the growth duration, but trim if the stock prices in >25x forward earnings without clear margin expansion.
• Pair trade: long COST / short a regional grocer or warehouse peer with weaker balance sheet flexibility over 6-12 months; the thesis is Costco’s scale and international optionality widen the valuation gap as pricing pressure intensifies.
• Buy COST call spreads 6-9 months out to express upside from continued international comp acceleration while limiting multiple-contraction risk if the market rotates away from defensives.
• If consumer data deteriorates over the next 1-2 quarters, use COST as a relative long versus discretionary retailers; membership value and trade-down behavior should make it a defensive winner even in softer demand.