Costco October Net Sales Jump 12.6% to $24.50B

What happened

Costco reported net sales of $24.50 billion for the retail month of October, up 12.6% from $21.75 billion a year ago. This headline growth significantly exceeds the company's recent adjusted comparable sales of 6%-7%, suggesting either a meaningful acceleration in core demand or a substantial contribution from gasoline price inflation. The DeepValue master report had modeled a base case of adjusted comps near 6% with fuel adding roughly 2-3 percentage points to total sales growth. Without details on comparable sales excluding gasoline, it is impossible to determine how much of the gain is fundamental, but the print is directionally positive. The news arrives ahead of November's Q4 FY26 earnings release, which will provide the next comprehensive look at margins, membership renewal, and post-fee-hike durability.

Implication

The 12.6% total sales growth is well above the base case's implied growth, potentially signaling stronger demand or fuel-driven tailwind. Without details on comparable sales excluding gasoline, it is premature to conclude that core growth accelerated. The report's valuation analysis suggests the stock already prices in robust growth, so a single strong month may not be sufficient to upgrade. Investors should monitor whether this momentum translates into higher adjusted comps and stable renewal rates in the upcoming quarterly earnings. The WAIT rating remains appropriate until there is evidence that the premium multiple can be justified by sustained post-fee-hike durability.

Thesis delta

The thesis remains that Costco's business quality is intact but the stock is fully valued. The October sales result is a positive data point that aligns with the bull case if adjusted comps are strong, but it does not by itself alter the valuation-based WAIT recommendation. The key shift to watch is whether this monthly strength persists into Q4 FY26 results and whether it is driven by core merchandise rather than gasoline.