WMA
COST icon

William Mack & Associates’s Costco COST Stock Holding History

William Mack & Associates’s Portfolio COST Stock Details COST Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q2 		$306K Buy
327
+71
+28% +$70.7K 0.11% 79
2026
Q1 		$255K Sell
256
-4
-2% -$3.9K 0.15% 62
2025
Q4 		$225K Sell
260
-8
-3% -$7.25K 0.11% 78
2025
Q3 		$248K Sell
268
-8
-3% -$7.67K 0.13% 70
2025
Q2 		$274K Hold
276
– – 0.17% 63
2025
Q1 		$261K Sell
276
-85
-24% -$82.9K 0.22% 58
2024
Q4 		$331K Buy
+361
New +$335K 0.35% 42

Other funds holding COST

BlackRock
BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return
Vanguard Capital Management
Vanguard Capital Management Malvern, Pennsylvania $4.68T AUM
State Street
State Street Boston, Massachusetts $3.37T AUM 44.26% 1-Year Est. Return
Invesco
Invesco Atlanta, Georgia $1.26T AUM 61.52% 1-Year Est. Return
Geode Capital Management
Geode Capital Management Boston, Massachusetts $1.88T AUM 44.46% 1-Year Est. Return
Vanguard Portfolio Management
Vanguard Portfolio Management Malvern, Pennsylvania $2.22T AUM
Morgan Stanley
Morgan Stanley New York $1.89T AUM 35.08% 1-Year Est. Return
Bank of America
Bank of America Charlotte, North Carolina $1.55T AUM 33.47% 1-Year Est. Return
Norges Bank
Norges Bank Oslo, Norway $1T AUM
Fidelity Investments
Fidelity Investments Boston, Massachusetts $2.3T AUM 54.33% 1-Year Est. Return

William Mack & Associates's COST Position: Q2 2026 in Review

William Mack & Associates increased its Costco (COST) stake by 28% in Q2 2026, buying an estimated $70.7K and bringing the position to 327 shares worth $306K. The position accounts for 0.11% of the portfolio, ranked #79.

William Mack & Associates first reported a position in COST in Q4 2024 and has held it in 7 quarters since. The position peaked at $331K in Q4 2024. 4,233 funds tracked by Wall St. Rank hold COST as of Q2 2026.

  • William Mack & Associates held 327 shares of Costco worth $306K as of Q2 2026.
  • William Mack & Associates bought 71 Costco shares in Q2 2026, an estimated $70.7K.
  • Costco made up 0.11% of William Mack & Associates's portfolio in Q2 2026, its #79 holding.
  • William Mack & Associates first reported a position in Costco in Q4 2024 and has held it in 7 quarters since.
  • William Mack & Associates's Costco position peaked at $331K in Q4 2024.
  • 4,233 funds tracked by Wall St. Rank held Costco as of Q2 2026.

Based on William Mack & Associates's 13F filing for Q2 2026, filed 10 Jul 2026.