Costco Wholesale's (COST) fiscal Q4 core earnings could fall short of Street estimates, excluding benefits from tariff refunds, Oppenheimer said in an earnings preview Wednesday.

The company is scheduled to report its quarterly results on Sept. 24.

Oppenheimer believes a fiscal Q4 consensus estimate of $6.55 is more of a best case scenario if management delivers on expense controls and does not reinvest excess fuel profits in the business. It expects a margin mix headwind related to fuel, ecommerce, and pharmacy, according to the note.

The brokerage said it views current levels as an attractive entry point, while it would take advantage of any weakness following the print rather than seeking a positive catalyst.

If Uber (UBER) gift cards return in-store, it could be a positive traffic driver for Costco, the note added.

Oppenheimer kept an outperform rating on Costco with a price target of $1,160.

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