Company: COST
Filing Date: 2025-06-27
Form Type: 11-K
Source: 0000909832-25-000038
Chunk: 3

Company: COSTCO WHOLESALE CORP /NEW
Filing Date: 2025-06-27
Form: 11-K
Chunk 3
---
 |     | Employee contributions                        |     |                   |     |      |          — |     |      |     43,139 |
|                                   |     |                                |     | Employer contributions                        |     |                   |     |      |    597,843 |     |      |    563,469 |
|                                   |     |                                |     |                                               |     | Total receivables |     |      |  1,185,017 |     |      |  1,166,602 |
|                                   |     | Non-interest bearing cash      |     |                                               |     |                   |     |      |      5,849 |     |      |      1,988 |
| Net assets available for benefits |     |                                |     |                                               |     |                   |     | $    | 41,017,392 |     | $    | 33,384,846 |

<div align='center'>See accompanying notes to financial statements.

2</div>

#### COSTCO 401(k) RETIREMENT PLAN
<div align='center'>Statement of Changes in Net Assets Available for Benefits

Year Ended December 31, 2024

(in thousands)</div>

| Net investment income:                               |     |                                 |     |                             |     | 2024 |            |
|:-----------------------------------------------------|:----|:--------------------------------|:----|:----------------------------|:----|:-----|-----------:|
|                                                      |     | Net appreciation of investments |     |                             |     | $    |  8,169,131 |
|                                                      |     | Interest                        |     |                             |     |      |     60,344 |
|                                                      |     | Dividends                       |     |                             |     |      |    548,716 |
|                                                      |     |                                 |     | Total net investment income |     |      |  8,778,191 |
| Interest on notes receivable from participants       |     |                                 |     |                             |     |      |     45,384 |
| Contributions to the Plan:                           |     |                                 |     |                             |     |      |            |
|                                                      |     | Employee                        |     |                             |     |      |  1,144,552 |
|                                                      |     | Employer                        |     |                             |     |      |    680,725 |
|                                                      |     |                                 |     | Total contributions         |     |      |  1,