Until what time may one make the second meal on Shabbat?

Hello,

Ideally, one should eat the Shabbat daytime meal before midday, and in any case begin it before midday. If one did not do so, one may still fulfill it afterward as well (see B"ach, siman 334, Maamar Mordechai, se'if katan 1, Mishnah Berurah, se'if katan 2, and siman 288, se'if katan 1, Aruch HaShulchan, se'if 2, Kaf HaChaim, siman 291, ot 2, Ohr L'Tzion, part 2, chapter 21, se'if 4), but one must be careful to taste at least something before midday, because it is forbidden to fast on Shabbat until six hours (see Shulchan Aruch, siman 288, se'if 1, and Mishnah Berurah, se'if katan 1).

With blessing,

Hillel Meirs