好市多批發公司
MX ˙ BMV ˙ US22160K1051
SecurityMX:COST / Costco Wholesale Corporation
InstitutionBath Savings Trust Co
Latest Disclosed Ownership24,492 shares
Latest Disclosed Value $ 24,404,563
Bath Savings Trust Co reports 1.20% increase in ownership of COST / Costco Wholesale Corporation

On April 7, 2026 - Bath Savings Trust Co filed a 13F-HR form disclosing ownership of 24,492 shares of Costco Wholesale Corporation (MX:COST) valued at $24,404,563 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 12, 2026 disclosing 24,202 shares of Costco Wholesale Corporation. This represents a change in shares of 1.20% during the quarter.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

Upgrade to unlock premium data and export to Excel .

Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-04-07 2026-03-31 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 24,492 290 1.20 24,405 16.93 2.6072
2026-01-12 2025-12-31 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 24,202 2,646 12.28 20,870 4.60 2.0831
2025-10-09 2025-09-30 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 21,556 42 0.20 19,953 -6.32 1.9754
2025-07-10 2025-06-30 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 21,514 -333 -1.52 21,298 3.07 2.1560
2025-04-07 2025-03-31 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 21,847 118 0.54 20,662 3.78 2.1372
2025-01-07 2024-12-31 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 21,729 -92 -0.42 19,910 2.92 2.0225
2024-10-07 2024-09-30 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 21,821 81 0.37 19,345 4.69 1.9220
2024-07-12 2024-06-30 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 21,740 335 1.57 18,479 17.84 1.4016
2024-07-12 2024-06-30 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 21,740 18,479
2024-04-08 2024-03-31 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 21,405 941 4.60 15,682 16.10 1.6646
2024-01-09 2023-12-31 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 20,464 882 4.50 13,508 22.09 1.5142
2023-10-12 2023-09-30 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 19,582 686 3.63 11,063 8.75 1.3593
2023-07-12 2023-06-30 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 18,896 574 3.13 10,173 11.75 1.1875
2023-04-12 2023-03-31 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 18,322 1,864 11.33 9,104 129,942.86 1.1207
2023-01-12 2022-12-31 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 16,458 1,519 10.17 8 -99.90 0.9692
2022-10-05 2022-09-30 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 14,939 470 3.25 7,055 1.73 0.9810
2022-07-07 2022-06-30 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 14,469 692 5.02 6,935 -12.58 0.9113
2022-04-07 2022-03-31 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 13,777 317 2.36 7,933 3.82 0.9053
2022-01-03 2021-12-31 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 13,460 114 0.85 7,641 27.41 0.7945
2021-10-06 2021-09-30 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 13,346 753 5.98 5,997 20.35 0.6933
2021-07-07 2021-06-30 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 12,593 2,370 23.18 4,983 38.26 0.5879
2021-04-08 2021-03-31 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 10,223 2,296 28.96 3,604 20.66 0.4600
2021-01-13 2020-12-31 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 7,927 1,410 21.64 2,987 29.08 0.3943
2020-10-01 2020-09-30 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 6,517 2,462 60.72 2,314 88.13 0.3796
2020-07-06 2020-06-30 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 4,055 2,370 140.65 1,230 156.25 0.2224
2020-04-01 2020-03-31 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 1,685 -75 -4.26 480 -7.16 0.1040
2020-01-09 2019-12-31 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 1,760 0 0.00 517 1.77 0.0934
2019-10-03 2019-09-30 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 1,760 200 12.82 508 23.00 0.0975
2019-07-01 2019-06-30 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 1,560 -30 -1.89 413 7.27 0.0821
2019-04-02 2019-03-31 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 1,590 -30 -1.85 385 16.67 0.0811
2019-01-04 2018-12-31 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 1,620 70 4.52 330 -9.34 0.0818
2018-10-05 2018-09-30 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 1,550 0 0.00 364 12.35 0.0795
2018-07-05 2018-06-30 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 1,550 0 0.00 324 10.96 0.0764
2018-04-03 2018-03-31 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 1,550 0 0.00 292 1.39 0.0730
2018-01-10 2017-12-31 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 1,550 0 0.00 288 12.94 0.0724
2017-10-02 2017-09-30 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 1,550 0 0.00 255 2.82 0.0681
2017-07-05 2017-06-30 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 1,550 1,550 248 0.0688
2016-04-13 2016-03-31 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 0 -1,247 -100.00 0 -100.00
2016-01-06 2015-12-31 13F COSTCO WHOLESALE CORP COM Common Stock 22160K105 1,247 1,247 202 0.0679
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.