Costco Wholesale Corporation
MX ˙ BMV ˙ US22160K1051
SecurityMX:COST / Costco Wholesale Corporation
InstitutionNwam Llc
Latest Disclosed Ownership20,897 shares
Latest Disclosed Value $ 20,822,029
Nwam Llc reports 0.70% decrease in ownership of COST / Costco Wholesale Corporation

On May 4, 2026 - Nwam Llc filed a 13F-HR form disclosing ownership of 20,897 shares of Costco Wholesale Corporation (MX:COST) valued at $20,822,029 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 4, 2026 disclosing 21,044 shares of Costco Wholesale Corporation. This represents a change in shares of -0.70% 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.

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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)
2026-05-04 2026-03-31 13F COSTCO WHOLESALE COM 22160K105 20,897 -147 -0.70 20,822 2.24 1.1982
2026-02-04 2025-12-31 13F COSTCO WHSL CORP COM 22160K105 21,044 -829 -3.79 20,366 -0.44 1.1379
2026-02-04 2025-09-30 13F/A-1 COSTCO WHSL CORP COM 22160K105 21,873 -358 -1.61 20,457 -2.48 1.1101
2025-10-28 2025-09-30 13F COSTCO WHSL CORP COM 22160K105 21,883 -348 20,638 1.4513
2026-02-04 2025-06-30 13F/A-1 COSTCO WHSL CORP COM 22160K105 22,231 485 2.23 20,978 1.99 1.2186
2025-08-07 2025-06-30 13F COSTCO WHSL CORP COM 22160K105 22,231 485 20,729 1.6869
2025-05-05 2025-03-31 13F COSTCO WHSL CORP COM 22160K105 21,746 -584 -2.62 20,567 0.52 1.7689
2025-02-05 2024-12-31 13F COSTCO WHSL CORP COM 22160K105 22,330 -294 -1.30 20,460 2.01 1.2650
2024-11-12 2024-09-30 13F COSTCO WHSL CORP COM 22160K105 22,624 22,624 20,056 1.2231
2024-07-24 2024-06-30 13F COSTCO WHSL CORP COM 22160K105 0 -20,630 -100.00 0 -100.00
2024-05-09 2024-03-31 13F COSTCO WHSL CORP COM 22160K105 20,630 -333 -1.59 15,844 14.50 1.2792
2024-02-14 2023-12-31 13F COSTCO WHSL CORP COM 22160K105 20,963 -179 -0.85 13,837 15.85 1.1115
2023-11-01 2023-09-30 13F COSTCO WHSL CORP COM 22160K105 21,142 -171 -0.80 11,945 4.10 1.2115
2023-08-10 2023-06-30 13F COSTCO WHSL CORP COM 22160K105 21,313 1,316 6.58 11,475 15.49 0.9427
2023-05-12 2023-03-31 13F COSTCO WHSL CORP COM 22160K105 19,997 -1,040 -4.94 9,936 3.46 1.0076
2023-02-08 2022-12-31 13F COSTCO WHSL CORP COM 22160K105 21,037 -44 -0.21 9,604 -3.55 0.8509
2022-11-14 2022-09-30 13F COSTCO WHSL CORP COM 22160K105 21,081 -303 -1.42 9,956 -4.48 0.9501
2022-08-10 2022-06-30 13F COSTCO WHSL CORP COM 22160K105 21,384 124 0.58 10,423 -14.87 0.9630
2022-05-12 2022-03-31 13F COSTCO WHSL CORP COM 22160K105 21,260 -751 -3.41 12,243 -2.02 0.9405
2022-02-10 2021-12-31 13F COSTCO WHSL CORP COM 22160K105 22,011 2,345 11.92 12,496 41.41 0.9879
2021-11-03 2021-09-30 13F COSTCO WHSL CORP COM 22160K105 19,666 1,983 11.21 8,837 26.30 0.8013
2021-08-04 2021-06-30 13F COSTCO WHSL CORP COM 22160K105 17,683 -67 -0.38 6,997 11.83 0.6491
2021-04-23 2021-03-31 13F COSTCO WHSL CORP COM 22160K105 17,750 1,014 6.06 6,257 -0.78 0.6229
2021-01-22 2020-12-31 13F COSTCO WHSL CORP COM 22160K105 16,736 141 0.85 6,306 7.04 0.7195
2020-10-16 2020-09-30 13F COSTCO WHSL CORP COM 22160K105 16,595 -1,766 -9.62 5,891 5.82 0.9719
2020-07-21 2020-06-30 13F COSTCO WHSL CORP COM 22160K105 18,361 380 2.11 5,567 8.58 0.7793
2020-04-16 2020-03-31 13F COSTCO WHSL CORP COM 22160K105 17,981 -3,035 -14.44 5,127 -17.00 0.1384
2020-01-23 2019-12-31 13F COSTCO WHSL CORP COM 22160K105 21,016 730 3.60 6,177 5.68 1.0681
2019-10-15 2019-09-30 13F COSTCO WHSL CORP COM 22160K105 20,286 1,090 5.68 5,845 15.22 1.0939
2019-07-18 2019-06-30 13F COSTCO WHSL CORP COM 22160K105 19,196 -3 -0.02 5,073 9.12 1.0099
2019-04-17 2019-03-31 13F COSTCO WHSL CORP COM 22160K105 19,199 280 1.48 4,649 20.63 1.0027
2019-01-30 2018-12-31 13F COSTCO WHSL CORP COM 22160K105 18,919 63 0.33 3,854 -12.98 0.9901
2018-10-09 2018-09-30 13F COSTCO WHSL CORP COM 22160K105 18,856 605 3.31 4,429 16.12 0.9955
2018-07-25 2018-06-30 13F/A-1 COSTCO WHSL CORP COM 22160K105 18,251 264 1.47 3,814 12.54 0.9033
2018-07-16 2018-06-30 13F COSTCO WHSL CORP COM 22160K105 18,251 264 3,814 0.3123
2018-04-16 2018-03-31 13F COSTCO WHSL CORP COM 22160K105 17,987 -101 -0.56 3,389 0.65 0.8562
2018-02-07 2017-12-31 13F COSTCO WHSL CORP COM 22160K105 18,088 326 1.84 3,367 15.39 0.8528
2017-11-01 2017-09-30 13F COSTCO WHSL CORP COM 22160K105 17,762 1,066 6.38 2,918 9.29 0.7585
2017-07-27 2017-06-30 13F COSTCO WHSL CORP COM 22160K105 16,696 1,478 9.71 2,670 4.62 0.4645
2017-05-01 2017-03-31 13F COSTCO WHSL CORP COM 22160K105 15,218 -399 -2.55 2,552 2.08 0.7787
2017-02-02 2016-12-31 13F COSTCO WHSL CORP COM 22160K105 15,617 803 5.42 2,500 10.67 0.8293
2016-10-26 2016-09-30 13F COSTCO WHSL CORP COM 22160K105 14,814 24 0.16 2,259 -2.76 0.1714
2016-08-04 2016-06-30 13F COSTCO WHSL CORP COM 22160K105 14,790 -1,110 -6.98 2,323 -7.30 0.9126
2016-05-16 2016-03-31 13F COSTCO WHSL CORP COM 22160K105 15,900 1,445 10.00 2,506 7.32 0.9929
2016-02-12 2015-12-31 13F COSTCO WHSL CORP COM 22160K105 14,455 455 3.25 2,335 12.15 0.9526
2015-11-17 2015-09-30 13F COSTCO WHSL CORP COM 22160K105 14,000 0 0.00 2,082 10.28 1.7271
2015-10-15 2015-06-30 13F COSTCO WHSL CORP COM 22160K105 14,000 247 1.80 1,888 -9.36 0.7898
2016-09-08 2015-03-31 13F COSTCO WHSL CORP COM 22160K105 13,753 268 1.99 2,083 9.00 0.8906
2016-09-08 2014-12-31 13F COSTCO WHSL CORP COM 22160K105 13,485 -6,923 -33.92 1,911 -25.29 0.8344
2016-09-08 2014-09-30 13F COSTCO WHSL CORP COM 22160K105 20,408 -4,604 -18.41 2,558 -11.18 0.9108
2016-09-08 2014-06-30 13F COSTCO WHSL CORP COM 22160K105 25,012 4 0.02 2,880 3.11 0.8959
2016-09-08 2014-03-31 13F COSTCO WHSL CORP COM 22160K105 25,008 9,828 64.74 2,793 54.57 0.9608
2016-09-08 2013-12-31 13F COSTCO WHSL CORP COM 22160K105 15,180 -3,577 -19.07 1,807 -16.34 0.9594
2016-09-08 2013-09-30 13F COSTCO WHSL CORP COM 22160K105 18,757 -711 -3.65 2,160 0.33 1.0492
2016-09-08 2013-06-30 13F COSTCO WHSL CORP COM 22160K105 19,468 -859 -4.23 2,153 -0.19 1.0884
2016-09-08 2013-03-31 13F COSTCO WHSL CORP COM 22160K105 20,327 -7,991 -28.22 2,157 -22.85 1.0602
2016-09-08 2012-12-31 13F COSTCO WHSL CORP COM 22160K105 28,318 404 1.45 2,796 0.00 1.1820
2016-09-08 2012-09-30 13F COSTCO WHSL CORP COM 22160K105 27,914 2,713 10.77 2,796 16.79 1.1745
2016-09-08 2012-06-30 13F COSTCO WHSL CORP COM 22160K105 25,201 25,201 2,394 1.1088
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.