This Sunday, July 17th is the fast of Shiva Asar B’Tamuz. This year the 17th of Tamuz falls on Shabbos, as such, the fast is a taanis nidcheh, and it is postponed until Sunday. Someone who feels unwell should consult a Rav as the obligation to fast on a taanis nidcheh may be somewhat more lenient.
The following Halachos are only for the Three weeks. Nine days is more strict.
Haircuts
⁃ Haircuts are not allowed for men or for women.
⁃ Shaving and trimming beards are not allowed.
⁃ Electrolysis, waxing, etc. for women is allowed.
⁃ If one is going to take a loss then shaving/haircuts are allowed until the week of tisha bav.
⁃ Mustache that prevents you from eating can be cut even during the week of tisha bav.
⁃ Wigs can be cut if necessary.
⁃ Nails can be cut up until the week of tisha bav.
⁃ If tisha bav falls out on Shabbos then nails can be cut on Erev Shabbos.
Music
⁃ No music or dancing even at a seudas mitzva. Singing is allowed.
⁃ Music tapes are not allowed.
⁃ Music lessons are allowed.
⁃ If necessary, slow inspirational or classical music is allowed.
⁃ Music for exercise is allowed.
⁃ Music to keep you up while you drive is allowed.
Shechayanu (clothing)
⁃ No shechayanu should be made at all.
⁃ No eating or buying new fruits because of the shechayanu.
⁃ Shechayanu on Shabbos is allowed.
⁃ Nowadays that most don’t make shechayanu on new clothes, a Sheila should be asked if you’re allowed to buy/wear new expensive clothing.
⁃ Clothing that’s not expensive can be bought and worn.
⁃ Expensive goes according to each persons means.
⁃ Clothing can be bought in order to be worn after the three weeks.
⁃ Large purchases are allowed but if they make you happy then you shouldn’t buy them.
Construction
⁃ Construction shouldn’t be done during the nine days and it’s better not to be done at all during the three weeks. If necessary a Sheila should be asked.
⁃ If it was started before the three weeks then it can be finished.
⁃ No moving into a new house, unless you have no place else to live.
⁃ Going to contract on a house is allowed.