Costco Wholesale Corporation
MX ˙ BMV ˙ US22160K1051
SecurityMX:COST / Costco Wholesale Corporation
InstitutionRMR Wealth Builders
Latest Disclosed Ownership6,187 shares
Latest Disclosed Value $ 6,165,195
RMR Wealth Builders reports 6.00% increase in ownership of COST / Costco Wholesale Corporation

On April 22, 2026 - RMR Wealth Builders filed a 13F-HR form disclosing ownership of 6,187 shares of Costco Wholesale Corporation (MX:COST) valued at $6,165,195 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 29, 2026 disclosing 5,837 shares of Costco Wholesale Corporation. This represents a change in shares of 6.00% 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)
2026-04-22 2026-03-31 13F COSTCO WHOLESALE COM 22160K105 6,187 350 6.00 6,165 22.49 0.4855
2026-01-29 2025-12-31 13F COSTCO WHSL CORP COM 22160K105 5,837 678 13.14 5,033 5.40 0.4027
2025-11-05 2025-09-30 13F COSTCO WHSL CORP COM 22160K105 5,159 290 5.96 4,776 -0.93 0.3997
2025-07-08 2025-06-30 13F COSTCO WHSL CORP COM 22160K105 4,869 75 1.56 4,820 6.31 0.4381
2025-04-16 2025-03-31 13F COSTCO WHSL CORP COM 22160K105 4,794 8 0.17 4,534 3.40 0.4772
2025-01-14 2024-12-31 13F/A-1 COSTCO WHSL CORP COM 22160K105 4,786 78 1.66 4,386 5.08 0.4533
2025-01-10 2024-12-31 13F COSTCO WHSL CORP COM 22160K105 4,786 78 4,386 0.4560
2024-10-21 2024-09-30 13F COSTCO WHSL CORP COM 22160K105 4,708 -123 -2.55 4,174 1.63 0.4423
2024-07-23 2024-06-30 13F COSTCO WHSL CORP COM 22160K105 4,831 252 5.50 4,106 22.42 0.4712
2024-04-15 2024-03-31 13F COSTCO WHSL CORP COM 22160K105 4,579 717 18.57 3,355 31.58 0.4056
2024-02-06 2023-12-31 13F COSTCO WHSL CORP COM 22160K105 3,862 369 10.56 2,549 29.19 0.3582
2023-10-23 2023-09-30 13F COSTCO WHSL CORP COM 22160K105 3,493 900 34.71 1,973 41.33 0.3152
2023-07-21 2023-06-30 13F COSTCO WHSL CORP COM 22160K105 2,593 -444 -14.62 1,396 -7.43 0.2375
2023-04-11 2023-03-31 13F COSTCO WHSL CORP COM 22160K105 3,037 248 8.89 1,509 18.55 0.2869
2023-02-15 2022-12-31 13F/A-1 COSTCO WHSL CORP COM 22160K105 2,789 7 0.25 1,273 -3.20 0.2886
2022-11-08 2022-09-30 13F COSTCO WHSL CORP COM 22160K105 2,782 45 1.64 1,314 0.15 0.3214
2022-08-02 2022-06-30 13F COSTCO WHSL CORP COM 22160K105 2,737 -139 -4.83 1,312 -20.77 0.3269
2022-05-13 2022-03-31 13F COSTCO WHSL CORP COM 22160K105 2,876 1,656 135.74 1,656 139.31 0.3552
2022-02-02 2021-12-31 13F COSTCO WHSL CORP COM 22160K105 1,220 -1,102 -47.46 692 -33.65 0.1987
2021-10-18 2021-09-30 13F COSTCO WHSL CORP COM 22160K105 2,322 84 3.75 1,043 17.85 0.3062
2021-08-16 2021-06-30 13F COSTCO WHSL CORP NEW COM Common Stock 22160K105 2,238 -108 -4.60 885 7.01 0.2901
2021-05-13 2021-03-31 13F COSTCO WHSL CORP COM 22160K105 2,346 380 19.33 827 11.61 0.2149
2021-02-26 2020-12-31 13F/A-1 COSTCO WHSL CORP COM 22160K105 1,966 -875 -30.80 741 -26.56 0.3640
2021-02-09 2020-12-31 13F COSTCO WHSL CORP COM 22160K105 1,321 -1,520 741 405,633.9879
2020-11-13 2020-09-30 13F COSTCO WHSL CORP COM 22160K105 2,841 1,005 54.74 1,009 81.15 0.2620
2020-08-19 2020-06-30 13F COSTCO WHSL CORP COM 22160K105 1,836 -134 -6.80 557 -3.80 0.4965
2020-03-03 2019-12-31 13F COSTCO WHOLESALE CORP COM USD0.01 COM 22160K105 1,970 1,970 579 0.5578
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.