I wear a tallit katan at almost all times and I do, in fact, sleep in it. I spoke to a rabbi about whether I would actually ever make "al mitzvat tzitzit" and it seemed that the answer was no. Kitzur also informs me that one doesn't make the blessing when putting on the tallit katan after a shower, as far as I know. So, if I'm donning a tallit gadol every morning for Shacharit, will I ever actually make "al mitzvat tzitzit" on a daily basis?
Will I ever actually make "al mitzvat tzitzit" on a daily basis if I don a tallit gadol?
2I know that the halacha is that one who dons a talit gadol for shacharit every morning does not make a b'racha on donning his talit katan. (If I have a chance to look up the sources later, I will post an answer if no one else has.) Personally, I have not made the b'racha al mitzvat tzitzit since I became bar mitzva and starting wearing a talit gadol.– jakeMay 22, 2011 at 20:06
For those wondering, I am yekke (of German descent), not sefardi.– jakeMay 22, 2011 at 21:55
Not on a daily basis, but maybe on a weekly basis if you put a different tallit katan on for Shabbos. Also, summer's coming up and if you go to the beach or the pool you'll almost invariably have your tallit katan off long enough for there to be hesech hadaas, so when you put it back on you'll make a bracha on it.
I think some people might argue that in both these cases you can have intention to cover these situations when you make your bracha in the morning, therefore would not make a bracha, but personally I never have the presence of mind to think that far ahead.
1Note that there are also many sefeqot brought down in the Mishnah Berurah (Siman 8) as regards a tallit qatan. And, since berakhot lo me'akvot, one would almost never make this berakhah.– LeeNov 28, 2015 at 16:31
at least sefaradim don't make this beracha, and i have yet to find a sidur with it. just because we say lehitatef everyday we also have intention on the talit catan, this is also part of the leshem ihud as rabenu iosef haim suggests