For reference, the following were last year's recognized Institute Holidays and Special Holidays and the day/dates on which they were observed. See current holidays.
| Holiday | Day | Date observed |
|---|---|---|
| New Year's Day |
January 1 | Monday, January 2, 2023 |
| Martin Luther King, Jr. Day |
3rd Monday in January | Monday, January 16, 2023 |
| Presidents Day |
3rd Monday in February | Monday, February 20, 2023 |
| Patriots' Day |
3rd Monday in April | Monday, April 17, 2023 |
| Memorial Day |
Last Monday in May | Monday, May 29, 2023 |
| Juneteenth |
June 19 | Monday, June 19, 2023 |
| Special Holiday Closing |
Monday, July 3 | Monday, July 3, 2023 |
| Independence Day |
July 4 | Tuesday, July 4, 2023 |
| Labor Day |
1st Monday in September | Monday, September 4, 2023 |
| Indigenous Peoples' Day |
2nd Monday in October | Monday, October 9, 2023 |
| Veterans Day |
November 11 | Friday, November 10, 2023 |
| Thanksgiving Day |
4th Thursday in November | Thursday, November 23, 2023 |
| Day After Thanksgiving |
Day after Thanksgiving | Friday, November 24, 2023 |
| Christmas Day |
December 25 | Monday, December 25, 2023 |
| Winter Break | Special Holiday Closing |
— | Tuesday, December 26, 2023 |
| Winter Break | Special Holiday Closing |
— | Wednesday, December 27, 2023 |
| Winter Break | Special Holiday Closing |
— | Thursday, December 28, 2023 |
| Winter Break | Special Holiday Closing |
— | Friday, December 29, 2023 |
| Winter Break | Special Holiday Closing |
— | Saturday, December 30, 2023 |
| Winter Break | Special Holiday Closing |
— | Sunday, December 31, 2023 |