COST monthly performance report
Monthly COST research: returns, drawdown, relative strength, seasonality, and key stats.
COST monthly report
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Key takeaways
- Costco (COST) closed September 2026 at $904.77, down 4.14% for the month and −6.18% over the trailing 12 months.
- Year-to-date, COST is +4.92%, underperforming the S&P 500 which has returned +12.08% YTD.
- The stock is trading −5.67% versus its 200-day moving average ($959.12), a cautious technical signal.
- Over the past three years, COST has underperformed the S&P 500 by −8.51%, with a relative strength index reading of 95.
- Win rate over the trailing 39 months stands at 51.3% — 20 positive months versus 19 negative months.
Costco ended September 2026 at $904.77, posting a monthly return of −4.14%. The S&P 500 returned −0.36% over the same window, leaving relative performance at −3.78%.
The current quarter stands at −3.28% (Q3 2026 (QTD)), while medium-term trend remains soft: price is −5.67% versus the 200-day moving average ($959.12).
Year-to-date, COST is +4.92% against SPY +12.08%, a gap of −7.16%. The stock is currently −17.49% below its 52-week high, with maximum 3-year drawdown at −21.07%.
| Period | COST | S&P 500 (SPY) | Excess return |
|---|---|---|---|
| 1 Day | +0.26% | +0.85% | −0.59% |
| 1 Week | −2.55% | −0.11% | −2.44% |
| 1 Month | −4.14% | −0.36% | −3.78% |
| 3 Months | −6.59% | +5.36% | −11.95% |
| 6 Months | −9.35% | +12.68% | −22.03% |
| YTD | +4.92% | +12.08% | −7.16% |
| 12 Months | −6.18% | +16.22% | −22.39% |
| 3 Years | +61.92% | +70.43% | −8.51% |
| Rank | Month | Return |
|---|---|---|
| #1 | May 2024 | +12.03% |
| #2 | Dec 2023 | +11.36% |
| #3 | Nov 2024 | +11.18% |
| #4 | Jan 2026 | +9.03% |
| #5 | Aug 2024 | +8.56% |
| Rank | Month | Return |
|---|---|---|
| #1 | Mar 2025 | −9.81% |
| #2 | May 2026 | −5.74% |
| #3 | Dec 2024 | −5.72% |
| #4 | Dec 2025 | −5.61% |
| #5 | Jul 2025 | −5.08% |
| Quarter | Return |
|---|---|
| Q2 2025 | +4.67% |
| Q3 2025 | −6.50% |
| Q4 2025 | −6.84% |
| Q1 2026 | +15.55% |
| Q2 2026 | −6.12% |
| Q3 2026 (QTD) | −3.28% |
| Year | Return |
|---|---|
| 2023 | +44.60% |
| 2024 | +38.81% |
| 2025 | −5.89% |
| 2026 | +4.92% |
| Metric | Value |
|---|---|
| 52-Week High | $1,096.50 (2026-05-19) |
| 52-Week Low | $844.06 (2025-12-16) |
| Current Price | $904.77 |
| 200-Day Moving Average | $959.12 |
| Price vs 200DMA | −5.67% |
| 3-Year Maximum Drawdown | −21.07% (2025-12-22) |
| Current Drawdown from 52W High | −17.49% |
| RS metric | Value |
|---|---|
| RS Index (3-year, rebased to 100) | 95 |
| 3-Year Excess Return vs S&P 500 | −8.51% |
| RS Peak | 151.6 (Apr 2025) |
| RS Trough | 95 (Sep 2026) |
| Status | Underperforming Benchmark |
Frequently asked questions
What was COST's return for this report period?
COST returned −4.14% in the latest monthly window ending 2026-09-11.
Has COST outperformed SPY year to date?
YTD COST: +4.92% vs SPY: +12.08%.
What is COST's 12-month return?
−6.18% over the trailing 12 months.
Is COST above or below its 200-day moving average?
Price is −5.67% versus 200DMA ($959.12).
What is the maximum drawdown in the 3-year window?
−21.07% on 2025-12-22.