Best Stock to Buy Right Now: Amazon vs. Costco

Amazon produced $143.3B in net sales in Q1 2024, up 12.5% year-over-year with Q2 guidance of $144–$149B (+7% to +11%), a trailing-12-month free cash flow of $46.1B (versus -$10.1B a year earlier) and $27.4B in net cash; AWS is accelerating toward a ~$100B revenue run rate. Costco reported fiscal Q3 2024 net sales of $57.4B (+9.1% YoY, calendar shift ~0.5–1%), May monthly sales of $19.64B (+8.1% YoY), trailing-12-month free cash flow of $7.4B and $4.6B net cash, while paying a $1.16 quarterly dividend (0.6% yield) and pursuing steady international expansion and membership-fee upside. The analyst view favors Amazon for higher growth potential and improved cash generation and relative valuation (42.8x FCF vs 10-year median 62.9), while Costco scores on capital returns and defensive, predictable growth.

Analysis

Market structure: Amazon (AMZN) is the primary winner — AWS and AI-infrastructure suppliers (NVDA, MSFT) capture pricing power while third‑party retailers and low‑margin grocers face margin pressure. Costco (COST) benefits from sticky membership demand (74.5M members, $4.8B fees) but its high FCF multiple (50.5x vs 31.1 median) signals crowded positioning; supply chains and fuel/transport costs remain key demand-margin levers. Cross-asset: stronger AMZN cash flows should compress credit spreads for tech names, lift risk assets and skew options vols lower; a macro slowdown would push bonds and defensive retail (COST) up in flight‑to‑quality trades.

Risk assessment: Tail risks include harsh AI regulation/antitrust on AWS, a China demand shock hitting Costco expansion, or Amazon’s AI capex overshooting and eroding FCF (capex could exceed 2023’s $48.4B materially). Immediate (days) risks: earnings-driven IV spikes; short term (weeks/months): guidance/ monthly sales surprises; long term (quarters/years): AWS ARR execution to $100B and membership fee timing. Hidden dependencies: AWS revenue concentration and Costco’s China consumer conversion rate (~200k members per new store) – execution here is binary. Key catalysts: AMZN quarterly (next 6–12 weeks) AWS metrics, COST monthly sales and any membership fee announcement.

Trade implications: Direct: establish a tactical 2–3% long AMZN allocation to capture AI/AWS re‑rate; use a 12–18 month defined‑risk call spread to limit capex shock exposure (e.g., Jan‑2026 450/650 call spread size to match 2–3% equity risk). For COST, prefer conservative exposure: buy on >5% pullback or sell cash‑secured puts 90–95% of spot for 45–90 days to collect premium; target holding 1–2%. Pair: small relative‑value long AMZN / short COST (2% / 1%) to express secular AI vs defensive retail over 9–12 months, rebalance if divergence >10%.

Key Decisions for Investors

• Establish a 2–3% tactical long position in AMZN within the next 2 weeks to play AWS/AI; implement with a 12–18 month defined‑risk call spread (example: Jan‑2026 450/650 call spread sized to equal a 2–3% equity exposure).
• Initiate a 1–2% position in COST on weakness (buy on >5% pullback) or sell cash‑secured puts at 90–95% of spot for 45–90 days to collect premium; target add if FCF multiple compresses to ~40x or membership fee is announced.
• Execute a 2% long AMZN / 1% short COST pair trade over a 9–12 month horizon to capture relative AI upside vs defensive retail; rebalance if P/L divergence exceeds 10% or if AMZN misses AWS ARR by >3 percentage points.
• Hedge downside: if AMZN guidance or AWS growth misses consensus by >3ppt, buy 3–4% notional of 3–6 month puts or tighten call spreads; if COST monthly sales decline >3% YoY across two consecutive months, reduce COST exposure to zero within 2 trading days.