The full Costco (COST) reaction history
COST news moved a median of -0.07% by the close. Every COST news event with the realized, point-in-time move the market made — the same measurement, headline by headline. Back to the COST overview →
Half of the 141 COST news events with a measured close landed between -0.85% and +0.48%; 48% closed up.
COST reaction counts across 4 years.
| Event type | 2026 | 2025 | 2024 | 2023 | Total |
|---|---|---|---|---|---|
| Press release | 16 | 28 | 29 | 6 | 79 |
| SEC filing · Form 8-K | 6 | 12 | 12 | 3 | 33 |
| SEC filing · Form 10-Q | 2 | 3 | 3 | 1 | 9 |
| SEC filing · Form 10-K | 0 | 1 | 1 | 1 | 3 |
| SEC filing · Form 11-K | 1 | 1 | 1 | 0 | 3 |
| SEC filing · Form ARS | 0 | 1 | 1 | 1 | 3 |
| SEC filing · Form DEF | 0 | 1 | 1 | 1 | 3 |
| SEC filing · Form DEFA14A | 0 | 1 | 1 | 1 | 3 |
| SEC filing · Form SD | 1 | 1 | 1 | 0 | 3 |
| SEC filing · Form IRANNOTICE | 0 | 0 | 0 | 1 | 1 |
| SEC filing · Form S-3ASR | 1 | 0 | 0 | 0 | 1 |
| SEC filing · Form S-8 | 0 | 0 | 1 | 0 | 1 |
| All types | 27 | 49 | 51 | 15 | 142 |
Counts from the full measured window for COST, not just the free rows below — every event type we have labeled, year by year.
Older COST news pages.
Page 1 is the COST overview; pages 2–3 carry the rest of the measured list.
The 10 most recent COST reactions.
| Date | Headline | Event | Source | 5-min | To close |
|---|---|---|---|---|---|
| Costco Wholesale Corporation Reports Fourth Quarter and Fiscal Year 2026 Operating Results | Press release | GlobeNewswire | +2.36% | +3.92% | |
| Form 8-K COSTCO WHOLESALE CORP For: Sep 24 | SEC filing · Form 8-K | SEC EDGAR | +2.36% | +3.92% | |
| Costco Wholesale Corporation Reports August Sales Results | Press release | GlobeNewswire | -0.76% | -0.28% | |
| Costco Wholesale Corporation Reports July Sales Results | Press release | GlobeNewswire | -0.01% | -1.08% | |
| Costco Wholesale Corporation Reports June Sales Results and Announces Quarterly Cash Dividend | Press release | GlobeNewswire | -0.89% | -1.83% | |
| Form 8-K COSTCO WHOLESALE CORP For: Jul 07 | SEC filing · Form 8-K | SEC EDGAR | -0.89% | -1.83% | |
| Form 11-K COSTCO WHOLESALE CORP For: Dec 31 | SEC filing · Form 11-K | SEC EDGAR | -0.10% | -1.24% | |
| Costco Wholesale Corporation Reports May Sales Results | Press release | GlobeNewswire | +0.08% | -1.48% | |
| Form 10-Q COSTCO WHOLESALE CORP For: May 10 | SEC filing · Form 10-Q | SEC EDGAR | +0.08% | -1.48% | |
| Form S-3ASR COSTCO WHOLESALE CORP | SEC filing · Form S-3ASR | SEC EDGAR | +0.08% | -1.48% |
132 more COST reactions are behind a free account. Create one to see all 142 measured COST events — the same point-in-time reactions, every headline.
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More COST: earnings → · analyst actions → · SEC filings → · COST overview →
Other Consumer Staples names, measured the same way
| Ticker | Events | Median 30-min | % positive |
|---|---|---|---|
| Coca-Cola (KO) | 2,000+ | -0.02% | 47% |
| Walmart (WMT) | 2,000+ | +0.01% | 52% |
Same sector, same measurement: percent move vs. the price at the news timestamp, read at 30 minutes. Sample sizes differ, so the medians are comparable but the confidence behind them is not.