Q) A choson is in his shono rishoino who makes his own seider, is he permitted to wear a kittl if he wants to?

A) M’kadesh Yisroel (Pesach 315) quotes Maharam Shick (O.C. 28) who endeavors to find a reason why some do not wear the Kitl during the first year after their wedding. He suggests that since on optimal circumstances, the choson should be married by eighteen years, and at that time he is not yet subject to punishments by the Hand of Heaven, there is no grounds for wearing a Kitl. However that does not apply to many today. He also mentions that the tradition of many Chasidim is to put on the Kitl on the first year, as one mayor rationale for using a kitl, is to resemble a Kohen when engaged in the Avodah of the Bais Hamikdosh, and Shono Rishonoh would not be an altering factor.

Hagodas Mibais Levy (From Horav Voshner shlit”a, p.57) mentions that the custom is to be lenient and wear the Kitl. See also Birur Halocho (quoted in Yemey Pesach p.194) that the one who wears it during the first year we let him do so.

Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit”a