1 | Sunday, 1 January 1640 |
New Year's Day |
| Monday, 2 January 1640 |
New Year's Day (observance) |
| Tuesday, 3 January 1640 |
January 2 (observance) |
2 | Monday, 9 January 1640 |
Coming of Age Day |
3 | Saturday, 11 February 1640 |
Foundation Day |
4 | Tuesday, 20 March 1640 |
Vernal Equinox Day |
5 | Sunday, 29 April 1640 |
Shōwa Day |
| Monday, 30 April 1640 |
Shōwa Day (observance) |
6 | Thursday, 3 May 1640 |
Constitution Memorial Day |
7 | Friday, 4 May 1640 |
Greenery Day |
8 | Saturday, 5 May 1640 |
Children's Day |
9 | Monday, 16 July 1640 |
Marine Day |
10 | Monday, 17 September 1640 |
Respect-for-Aged Day |
11 | Sunday, 23 September 1640 |
Autumnal Equinox Day |
| Monday, 24 September 1640 |
Autumnal Equinox Day (observance) |
12 | Monday, 8 October 1640 |
Health and Sports Day |
13 | Saturday, 3 November 1640 |
Culture Day |
14 | Friday, 23 November 1640 |
Labor Thanksgiving Day |
15 | Sunday, 23 December 1640 |
Emperor's Birthday |
| Monday, 24 December 1640 |
Emperor's Birthday (observance) |
16 | Monday, 31 December 1640 |
New Year's Eve |