Costco (COST)

How COST actually reacts to news — the realized, point-in-time move the market made, measured across 2,000+ labeled events over the last three years with zero look-ahead.

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The quantified answer

COST’s median reaction, across the day.

-0.02%

Median 30-min

Typical reaction 30 minutes after any COST news

48%

Moved up

Share of COST news events that rose at 30 minutes

+0.00%

Median to close

Where COST typically settles by the closing bell

Median move vs. the price at the news timestamp, across 2,000+ labeled events.

By event type

How COST reacts, by analyst action.

Event	Events	Median 30-min	% positive	Median to close
Analyst upgrades	21	+0.43%	81%	+0.81%
Analyst downgrades	28	-0.45%	33%	-0.54%
Coverage initiations	25	+0.08%	64%	+0.28%
Rating reiterations	342	-0.04%	47%	+0.04%
Price-target raises	150	-0.08%	43%	+0.05%
Price-target cuts	22	-0.39%	18%	+0.05%

Last 3 years, pulled 2026-07-14. Reaction = percent move vs. the price at the news timestamp. The same measurement runs across every name in the dataset.

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Recent COST events, each with its measured reaction. (Page 1 of 3.)

Date	Headline	Event	Source	5-min	To close
Aug 5, 2026	Costco Wholesale Corporation Reports July Sales Results	Press release	GlobeNewswire	-0.01%	-1.08%
Jul 8, 2026	Costco Wholesale Corporation Reports June Sales Results and Announces Quarterly Cash Dividend	Press release	GlobeNewswire	-0.89%	-1.83%
Jul 8, 2026	Form 8-K COSTCO WHOLESALE CORP For: Jul 07	SEC filing · Form 8-K	SEC EDGAR	-0.89%	-1.83%
Jun 29, 2026	Form 11-K COSTCO WHOLESALE CORP For: Dec 31	SEC filing · Form 11-K	SEC EDGAR	-0.10%	-1.24%
Jun 3, 2026	Costco Wholesale Corporation Reports May Sales Results	Press release	GlobeNewswire	+0.08%	-1.48%
Jun 3, 2026	Form 10-Q COSTCO WHOLESALE CORP For: May 10	SEC filing · Form 10-Q	SEC EDGAR	+0.08%	-1.48%
Jun 3, 2026	Form S-3ASR COSTCO WHOLESALE CORP	SEC filing · Form S-3ASR	SEC EDGAR	+0.08%	-1.48%
May 29, 2026	Form SD COSTCO WHOLESALE CORP	SEC filing · Form SD	SEC EDGAR	-1.37%	-3.07%
May 28, 2026	Costco Wholesale Corporation Reports Third Quarter and Year-To-Date Operating Results For Fiscal 2026	Press release	GlobeNewswire	-1.37%	-3.07%
May 28, 2026	Form 8-K COSTCO WHOLESALE CORP For: May 28	SEC filing · Form 8-K	SEC EDGAR	-1.37%	-3.07%
May 6, 2026	Costco Wholesale Corporation Reports April Sales Results	Press release	GlobeNewswire	+0.45%	+1.87%
Apr 15, 2026	Costco Wholesale Corporation Announces an Increase in Its Quarterly Cash Dividend	Press release	GlobeNewswire	+0.06%	+0.22%
Apr 15, 2026	Form 8-K COSTCO WHOLESALE CORP For: Apr 15	SEC filing · Form 8-K	SEC EDGAR	+0.06%	+0.22%
Apr 9, 2026	Edna’s Margarita Mix Returns to Costco Wholesale - Better Than Ever	Press release	Business Wire	+0.07%	+0.25%
Apr 8, 2026	Costco Wholesale Corporation Reports March Sales Results	Press release	GlobeNewswire	+0.07%	+0.25%
Mar 27, 2026	Canada’s Eleventh Costco Business Centre is now open in Winnipeg	Press release	GlobeNewswire	-0.46%	-0.07%
Mar 11, 2026	Form 10-Q COSTCO WHOLESALE CORP For: Feb 15	SEC filing · Form 10-Q	SEC EDGAR	-0.06%	+1.60%
Mar 5, 2026	Costco Wholesale Corporation Reports Second Quarter and Year-to-Date Operating Results for Fiscal 2026 and February Sales Results	Press release	GlobeNewswire	+1.15%	+3.64%
Mar 5, 2026	Form 8-K COSTCO WHOLESALE CORP For: Mar 05	SEC filing · Form 8-K	SEC EDGAR	+1.15%	+3.64%
Feb 4, 2026	Costco Wholesale Corporation Reports January Sales Results	Press release	GlobeNewswire	-0.25%	-0.62%
Jan 21, 2026	Form 8-K COSTCO WHOLESALE CORP For: Jan 15	SEC filing · Form 8-K	SEC EDGAR	+0.36%	-0.18%
Jan 15, 2026	Costco Wholesale Corporation Announces Quarterly Cash Dividend	Press release	GlobeNewswire	-0.22%	+0.46%
Jan 13, 2026	Koia Marks the Next Phase of Protein Category Leadership as it Enters into Clear Protein with the Launch of Protein Pop	Press release	PR Web	-0.06%	+0.42%
Jan 7, 2026	Costco Wholesale Corporation Reports December Sales Results	Press release	GlobeNewswire	-0.13%	+1.66%
Dec 17, 2025	Form 10-Q COSTCO WHOLESALE CORP For: Nov 23	SEC filing · Form 10-Q	SEC EDGAR	+0.07%	-0.16%
Dec 11, 2025	Costco Wholesale Corporation Reports First Quarter Fiscal Year 2026 Operating Results	Press release	GlobeNewswire	-0.49%	+0.05%
Dec 11, 2025	Form 8-K COSTCO WHOLESALE CORP For: Dec 11	SEC filing · Form 8-K	SEC EDGAR	-0.49%	+0.05%
Dec 6, 2025	Canada’s Tenth Costco Business Centre is now open in East Gwillimbury	Press release	GlobeNewswire	-0.16%	-0.67%
Dec 4, 2025	Costco Wholesale Corporation Announces Nomination of Gina Raimondo to Board of Directors	Press release	GlobeNewswire	+0.03%	-0.31%
Dec 4, 2025	Form ARS COSTCO WHOLESALE CORP For: Aug 31	SEC filing · Form ARS	SEC EDGAR	+0.03%	-0.31%
Dec 4, 2025	Form DEF 14A COSTCO WHOLESALE CORP For: Aug 31	SEC filing · Form DEF	SEC EDGAR	+0.03%	-0.31%
Dec 4, 2025	Form DEFA14A COSTCO WHOLESALE CORP	SEC filing · Form DEFA14A	SEC EDGAR	+0.03%	-0.31%
Dec 3, 2025	Costco Wholesale Corporation Reports November Sales Results	Press release	GlobeNewswire	-0.72%	-1.21%
Nov 14, 2025	Canada’s Eighth Costco Business Centre is now open in New Westminster	Press release	GlobeNewswire	+0.24%	+0.48%
Nov 13, 2025	Costco Wholesale Opens New Location in W. Winnipeg	Press release	GlobeNewswire	-0.39%	—
Nov 5, 2025	Costco Wholesale Corporation Reports October Sales Results	Press release	GlobeNewswire	-1.05%	-0.08%
Oct 28, 2025	Canada’s Seventh Costco Business Centre is now open in Mississauga	Press release	GlobeNewswire	-0.01%	-0.29%
Oct 20, 2025	Form 8-K COSTCO WHOLESALE CORP For: Oct 14	SEC filing · Form 8-K	SEC EDGAR	-0.01%	+0.15%
Oct 15, 2025	Costco Wholesale Corporation Announces Quarterly Cash Dividend	Press release	GlobeNewswire	-0.71%	-3.13%
Oct 15, 2025	Form 8-K COSTCO WHOLESALE CORP For: Oct 15	SEC filing · Form 8-K	SEC EDGAR	-0.71%	-3.13%
Oct 8, 2025	Costco Wholesale Corporation Reports September Sales Results	Press release	GlobeNewswire	+0.30%	+1.14%
Oct 8, 2025	Form 10-K COSTCO WHOLESALE CORP For: Aug 31	SEC filing · Form 10-K	SEC EDGAR	-0.09%	+0.09%
Sep 25, 2025	Costco Wholesale Corporation Reports Fourth Quarter and Fiscal Year 2025 Operating Results	Press release	GlobeNewswire	-1.48%	-1.08%
Sep 25, 2025	Form 8-K COSTCO WHOLESALE CORP For: Sep 25	SEC filing · Form 8-K	SEC EDGAR	-1.48%	-1.08%
Sep 4, 2025	Costco Wholesale Corporation Reports August Sales Results	Press release	GlobeNewswire	+0.36%	+0.50%
Sep 4, 2025	Shake It Up: Burger Lounge Partners with Klimon for Dairy-Free Indulgence	Press release	PR Web	+0.36%	+0.50%
Aug 7, 2025	Form 8-K COSTCO WHOLESALE CORP For: Aug 04	SEC filing · Form 8-K	SEC EDGAR	+0.48%	+0.39%
Aug 6, 2025	Costco Wholesale Corporation Reports July Sales Results	Press release	GlobeNewswire	+0.44%	+0.28%
Jul 17, 2025	Edna’s Selected to Exhibit at INFRA’s 2025 Tabletop Show—Raising the Bar on Non-Alcoholic Sparkling Cocktails	Press release	Business Wire	-0.03%	+0.35%
Jul 16, 2025	Costco Wholesale Corporation Announces Quarterly Cash Dividend	Press release	GlobeNewswire	-0.10%	+0.37%

Each headline opens its own page with the full realized reaction — the move the market actually made, measured from the news timestamp.

Keep exploring

More of the dataset.

COST earnings → · Analyst actions → · SEC filings → · Full history →

Every ticker we measure the same way24

Costco (COST)

COST’s median reaction, across the day.

How COST reacts, by analyst action.

Email me when COST moves on news.

Get “How COST reacts to news” as a PDF.

Recent COST events, each with its measured reaction. (Page 1 of 3.)

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Costco (COST)

COST’s median reaction, across the day.

How COST reacts, by analyst action.

Email me when COST moves on news.

Get “How COST reacts to news” as a PDF.

Recent COST events, each with its measured reaction. (Page 1 of 3.)

More of the dataset.

Apple (AAPL)

NVIDIA (NVDA)

Tesla (TSLA)

Microsoft (MSFT)

Advanced Micro Devices (AMD)

Amazon (AMZN)

Alphabet (GOOG)

Meta Platforms (META)

Broadcom (AVGO)

JPMorgan Chase (JPM)

Visa (V)

Walmart (WMT)

Eli Lilly (LLY)

UnitedHealth Group (UNH)

Netflix (NFLX)

Johnson & Johnson (JNJ)

Exxon Mobil (XOM)

Home Depot (HD)

Mastercard (MA)

Oracle (ORCL)

Salesforce (CRM)

Bank of America (BAC)

Coca-Cola (KO)

Walt Disney (DIS)

Browse all tickers

You just saw one reaction.There are 26 million more.

Know the next move, measured.

The dataset, one command away.

You just saw one reaction.
There are 26 million more.