Nine Days: Laundry/Adding clothes
Question
I am running out of underwear for the 9 days and I will need to do a small load. 1-is that OK? I assume so. 2-can I include other garments in that load even if I will not wear the other garments until after Tisha bav. Please let me know. Thank you
Answer
Shalom!
Thank you for your question.
You are permitted to wear your new underwear during the Nine Days if you have no others that fit, however, it is best if you wait to wear it on Shabbos for the first time. If you can't wait till then, you can wear it on the weekdays however, it is preferable that these garments should first be "dirtied" by putting them on the floor.
If you must wash your underwear, if it is during the first part of the Nine Days it is better to wash your underwear than to purchase new underwear. However, during the week in which Tisha B’av falls (“shavua shechal bo”) it would be preferable to buy new underwear rather than to wash the underwear. Again, they should be first be made “dirtied” by putting them on the floor.
It is interesting to note that as a general rule the ban on buying new garments during the Nine Days is a custom found in the Jerusalem Talmud, while the ban on washing clothes during the Nine Days is an actual law from the Babylonian Talmud, and, therefore, treated more stringently accordingly.
Even when it is permitted to wash clothes, you are only permitted to wash those specific clothes. It is not permitted to add other clothes to the washing machine even for use after Tisha B’av.
The answers above only apply to your specific case in which the garments in question directly touch the skin. The halacha is a little more stringent for clothes that do not touch the skin.
Source
OC 551:7 and commentaries.