To what extent am I obligated to eat matza during Pesach other than at the seder?

Although halachically one neither receives punishment for refraining nor reward for eating matza at other times throughout Pesach,¹ the Chizkuni notes that one nonetheless fulfills the possuk, “Seven days you shall eat matzos,”² and some add that there is even reward for this.³

Several Midrashim support this idea, highlighting the spiritual advantage of eating matza throughout Pesach,⁴ and the Rambam points out that because we eat matzah for seven consecutive days, the experience leaves a lasting impression.⁵ The Rebbe explains that eating matzah during the subsequent days of Pesach enhances one’s emuna, and therefore it is preferable not to use machine-made matza for these days.

Nevertheless, on Shabbos and Yom Tov of Pesach, there are practical requirements that involve matzah: For kiddush to be valid (bimkom seuda), one must eat matzah (or one may drink an additional revi’is of wine), and seudas yom tov also requires one to eat matza.

How much matzah is required in these cases?

For kiddush bimkom seuda, and seudas yom tov, a kazayis of matzah is generally sufficient (though a kabeitza is required if reciting the bracha “al netilas yadayim”).⁶ And since these are derabanan obligations (unlike Seder matza, which is from the Torah), one can follow the smaller view on kezayis, which is one-third of an egg’s volume.

For birkas hamazon, however, one should ensure to eat the larger kezayis measure (half an egg’s volume), as eating less would create a doubt whether to recite the bracha (safek brachos l’hakel).⁷

When measuring kazayis by volume (its inherent method), it ends up being less matza than when measuring by weight.

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