Costco's financial profile is simultaneously straightforward in structure and extraordinary in performance — a business that generates enormous revenues at modest margins but whose underlying economics are far more attractive than the headline margin figures suggest. The key to understanding Costco's financial model is disaggregating the near-zero-margin merchandise business from the near-100%-margin membership fee business, and recognizing that the former exists primarily to justify and support the latter. Total revenues for fiscal year 2023 reached approximately 242 billion dollars, representing year-over-year growth of approximately 7% — a growth rate that is impressive given the company's already enormous scale. Revenue has grown consistently throughout Costco's history, with only the COVID-19 pandemic period creating meaningful disruption to the historical trajectory. Net sales — the merchandise and service revenue component — comprised approximately 237 billion dollars of total revenue, with membership fees contributing approximately 4.6 billion dollars. This revenue split reveals the fundamental dynamic: membership fees represent approximately 2% of total revenues but approximately 70–75% of operating income, making Costco's financial performance almost entirely dependent on membership fee economics. Gross margins on merchandise have been deliberately maintained in the 12–13% range — a figure that appears low in absolute terms but represents near-maximum efficiency given Costco's pricing philosophy. The company's selling, general, and administrative expense ratio — approximately 9–10% of net sales — is among the lowest in all of retail, reflecting the cost efficiency of the warehouse format, the limited SKU count that reduces inventory management complexity, and the membership model that eliminates most conventional retail marketing spend. The combination of gross margin and SGA efficiency produces operating margins of approximately 6–7% on total revenues — extraordinary for a retailer of Costco's scale. Net income reached approximately 6.3 billion dollars in fiscal year 2023, representing a net margin of approximately 2.6% on total revenues. This figure understates the quality of Costco's earnings, as the business is exceptionally capital-efficient: return on invested capital consistently runs above 20–25%, driven by the high inventory turnover (approximately 12 times annually) and the membership fee cash flow that is essentially pure profit. The membership fee growth trajectory is the most important financial indicator for long-term investors. Fee revenue has grown from approximately 2.8 billion dollars in fiscal year 2015 to 4.6 billion dollars in fiscal year 2023 — a compound annual growth rate of approximately 6.5%. This growth is driven by a combination of new warehouse openings that add new members, gradual shifts in the membership mix toward the higher-fee Executive tier, and periodic fee increases. Costco implemented its most recent US membership fee increase in September 2024 — the first increase since 2017 — raising Gold Star membership from 60 dollars to 65 dollars and Executive from 120 dollars to 130 dollars. The market's reaction to this announcement was uniformly positive, with analysts projecting that the fee increase would add approximately 400–500 million dollars in annual fee revenue given the near-universal membership renewal rate. Capital allocation reflects the confidence of management and the board in the business's earnings durability. Costco pays a regular quarterly dividend — currently yielding approximately 0.7–0.9% — and periodically declares large special dividends when the balance sheet accumulates excess cash, including special dividends of 7, 10, and 15 dollars per share in 2012, 2017, and 2020 respectively. Share repurchases are modest relative to free cash flow, reflecting a preference for returning capital through dividends rather than buybacks. Capital expenditure runs at approximately 4–5 billion dollars annually, funding new warehouse construction and existing warehouse renovations.