Costco Wholesale Corporation
MX ˙ BMV ˙ US22160K1051
SecurityMX:COST / Costco Wholesale Corporation
InstitutionHallmark Capital Management Inc
Latest Disclosed Ownership975 shares
Latest Disclosed Value $ 971,519
Hallmark Capital Management Inc reports 3.66% decrease in ownership of COST / Costco Wholesale Corporation

On May 6, 2026 - Hallmark Capital Management Inc filed a 13F-HR form disclosing ownership of 975 shares of Costco Wholesale Corporation (MX:COST) valued at $971,519 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 4, 2026 disclosing 1,012 shares of Costco Wholesale Corporation. This represents a change in shares of -3.66% 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)
2026-05-06 2026-03-31 13F COSTCO WHOLESALE CORPORATION COM Stock 22160K105 975 -37 -3.66 972 11.35 0.0570
2026-02-04 2025-12-31 13F COSTCO WHOLESALE CORPORATION COM Stock 22160K105 1,012 -34 -3.25 873 -9.92 0.0559
2025-11-03 2025-09-30 13F COSTCO WHSL CORP NEW COM Stock 22160K105 1,046 -82 -7.27 968 -13.26 0.0640
2025-08-06 2025-06-30 13F COSTCO WHSL CORP NEW COM Stock 22160K105 1,128 -76 -6.31 1,117 -1.93 0.0803
2025-05-07 2025-03-31 13F COSTCO WHSL CORP NEW COM Stock 22160K105 1,204 26 2.21 1,139 5.47 0.0864
2025-01-31 2024-12-31 13F COSTCO WHSL CORP NEW COM Stock 22160K105 1,178 46 4.06 1,080 7.58 0.0807
2024-11-06 2024-09-30 13F COSTCO WHSL CORP NEW COM Stock 22160K105 1,132 25 2.26 1,004 6.59 0.0744
2024-08-08 2024-06-30 13F COSTCO WHSL CORP NEW COM Stock 22160K105 1,107 70 6.75 941 23.98 0.0750
2024-05-03 2024-03-31 13F COSTCO WHSL CORP NEW COM Stock 22160K105 1,037 73 7.57 760 19.34 0.0573
2024-02-07 2023-12-31 13F COSTCO WHSL CORP NEW COM Stock 22160K105 964 6 0.63 637 17.56 0.0496
2023-11-09 2023-09-30 13F COSTCO WHSL CORP NEW COM Stock 22160K105 958 22 2.35 541 7.34 0.0451
2023-07-28 2023-06-30 13F COSTCO WHSL CORP NEW COM Stock 22160K105 936 -55 -5.55 504 2.44 0.0453
2023-05-03 2023-03-31 13F COSTCO WHSL CORP NEW COM Stock 22160K105 991 4 0.41 493 9.33 0.0448
2023-02-01 2022-12-31 13F COSTCO WHSL CORP NEW COM Stock 22160K105 987 -17 -1.69 451 -5.06 0.0418
2022-11-09 2022-09-30 13F COSTCO WHSL CORP NEW COM Stock 22160K105 1,004 77 8.31 474 6.52 0.0473
2022-11-16 2022-06-30 13F/A-3 COSTCO WHSL CORP NEW COM Stock 22160K105 927 -200 -17.75 445 -31.43 0.0417
2022-08-01 2022-06-30 13F COSTCO WHSL CORP NEW COM Stock 22160K105 927 -200 444 0.0416
2022-05-02 2022-03-31 13F COSTCO WHOLESALE COM 22160K105 1,127 -11 -0.97 649 0.46 0.0542
2022-02-02 2021-12-31 13F COSTCO WHOLESALE COM 22160K105 1,138 0 0.00 646 26.42 0.0518
2021-11-01 2021-09-30 13F COSTCO WHOLESALE COM 22160K105 1,138 -100 -8.08 511 4.29 0.0446
2021-08-03 2021-06-30 13F COSTCO WHOLESALE COM 22160K105 1,238 140 12.75 490 26.94 0.0414
2021-04-22 2021-03-31 13F COSTCO WHOLESALE COM 22160K105 1,098 0 0.00 386 -6.54 0.0347
2021-02-02 2020-12-31 13F COSTCO WHOLESALE COM 22160K105 1,098 -105 -8.73 413 -3.28 0.0404
2020-11-03 2020-09-30 13F COSTCO WHOLESALE COM 22160K105 1,203 133 12.43 427 31.38 0.0470
2020-07-28 2020-06-30 13F COSTCO WHOLESALE COM 22160K105 1,070 -45 -4.04 325 2.20 0.0364
2020-04-24 2020-03-31 13F COSTCO WHOLESALE COM 22160K105 1,115 -60 -5.11 318 -8.09 0.0413
2020-01-31 2019-12-31 13F COSTCO WHOLESALE COM 22160K105 1,175 0 0.00 346 2.06 0.0346
2019-11-01 2019-09-30 13F COSTCO WHOLESALE COM 22160K105 1,175 -90 -7.11 339 1.19 0.0360
2019-08-08 2019-06-30 13F COSTCO WHOLESALE COM 22160K105 1,265 100 8.58 335 18.79 0.0356
2019-05-09 2019-03-31 13F COSTCO WHOLESALE COM 22160K105 1,165 -400 -25.56 282 -11.60 0.0308
2019-02-08 2018-12-31 13F COSTCO WHOLESALE COM 22160K105 1,565 400 34.33 319 16.42 0.0417
2018-10-26 2018-09-30 13F COSTCO WHOLESALE COM 22160K105 1,165 1,165 274 0.0324
2017-07-13 2017-06-30 13F Costco Wholesale COM 22160K105 0 -200 -100.00 0 -100.00
2017-05-12 2017-03-31 13F Costco Wholesale COM 22160K105 200 -11 -5.21 34 0.00 0.0045
2017-02-13 2016-12-31 13F Costco Wholesale COM 22160K105 211 11 5.50 34 9.68 0.0049
2016-11-09 2016-09-30 13F Costco Wholesale COM 22160K105 200 -400 -66.67 31 -67.02 0.0046
2016-08-05 2016-06-30 13F Costco Wholesale COM 22160K105 600 600 94 0.0143
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.