Siman 199
Presented here for study, not as a practical ruling. The Shulchan Aruch rules by Sephardi custom, the Rema's glosses by Ashkenazi custom, and the Kitzur follows Ashkenazi custom. For a practical question, ask your rabbi.
א הַשַּׁמָּשׁ שֶׁאָכַל כַּזַּיִת מְזַמְּנִין עָלָיו.
1 The waiter who ate an olive’s worth may be included in the zimun.
ב כּוּתִי בַּזְּמַן הַזֶּה הֲרֵי הוּא כְּעוֹבֵד עֲבוֹדַת אֱלִילִים וְאֵין מְזַמְּנִין עָלָיו.
2 Nowadays, Cutheans are the same as idolaters and are not included in a zimun
ג עַם הָאָרֶץ גָּמוּר מְזַמְּנִין עָלָיו בַּזְּמַן הַזֶּה.
3 Someone who is an absolute am ha’aretz is included in a zimun nowadays
ד עוֹבֵד כּוֹכָבִים אֵין מְזַמְּנִין עָלָיו, וַאֲפִלּוּ גֵּר שֶׁמָּל וְלֹא טָבַל אֵין מְזַמְּנִין עָלָיו; אֲבָל גֵּר גָּמוּר מְזַמְּנִין עָלָיו וְיָכוֹל לְבָרֵךְ בִּרְכַּת הַמָּזוֹן וְלוֹמַר: עַל שֶׁהִנְחַלְתָּ לַאֲבוֹתֵינוּ.
4 A gentile is not included in a zimun. Even a convert who was circumcised but did not immerse may not be included in a zimun. Someone who is a full fledged convert is included in a zimun and he may recite birkas hamazon including the words Al Shehinchalta La'avoteinu
ה אוֹנֵן בַּחֹל, שֶׁהוּא פָּטוּר מִלְּבָרֵךְ, אֵין מְזַמְּנִין עָלָיו.
5 An onen (on a weekday), that is exempt from blessing, may not be included in a zimun.
ו נָשִׁים וַעֲבָדִים וּקְטַנִּים אֵין מְזַמְּנִין עֲלֵיהֶם, אֲבָל מְזַמְּנִין לְעַצְמָן; וְלֹא תְּהֵא חֲבוּרָה שֶׁל נָשִׁים וַעֲבָדִים וּקְטַנִּים מְזַמְּנִין יַחַד, מִשּׁוּם פְּרִיצוּתָא דַּעֲבָדִים, אֶלָּא נָשִׁים לְעַצְמָן וַעֲבָדִים לְעַצְמָם; וּבִלְבַד שֶׁלֹּא יְזַמְּנוּ בְּשֵׁם.
6 We do not make a zimun with women, slaves or children but they may make a zimun by themselves. A zimun comprised of women, slaves and children should not be formed due to the promiscuity of the slaves, rather women should recite birkas hamazon by themselves and slaves by themselves but they may not use Hashem’s Name
ז נָשִׁים מְזַמְּנוֹת לְעַצְמָן, רְשׁוּת. אֲבָל כְּשֶׁאוֹכְלוֹת עִם הָאֲנָשִׁים, חַיָּבוֹת וְיוֹצְאוֹת בַּזִּמּוּן שֶׁלָּנוּ. הַגָּה: אַף עַל פִּי שֶׁאֵינָן מְבִינוֹת (הָרֹא"שׁ וּמָרְדְּכַי רֵישׁ פ' ג' שֶׁאָכְלוּ בְּשֵׁם רַשִׁ"י).
7 Women have the option to form a zimun by themselves but when they eat with men they are obligated to answer and they fulfill their obligation by listening to the men Rem'a: even though they do not understand lashon kodesh
ח אַנְדְּרוֹגִינוּס מְזַמֵּן לְמִינוֹ, וְאֵינוֹ מְזַמֵּן לֹא לָאֲנָשִׁים וְלֹא לְנָשִׁים.
8 An androgynous makes a zimun with other androgynous, and he cannot be included in the zimun of men or women.
ט טֻמְטוּם אֵינוֹ מְזַמֵּן כְּלָל.
9 A tum tum never makes a zimun
י קָטָן שֶׁהִגִּיעַ לְעוֹנַת הַפָּעוֹטוֹת וְיוֹדֵעַ לְמִי מְבָרְכִין, מְזַמְּנִין עָלָיו וּמִצְטָרֵף בֵּין לִשְׁלֹשָׁה בֵּין לַעֲשָׂרָה. הַגָּה: וְיֵשׁ אוֹמְרִים דְּאֵין מִצְטָרְפִין אוֹתוֹ כְּלָל עַד שֶׁיְּהֵא בֶּן שְׁלֹשׁ עֶשְׂרֵה שָׁנָה דְּאָז מְחַזְּקִינַן לֵיהּ כְּגָדוֹל שֶׁהֵבִיא ב' שְׂעָרוֹת (הָרֹא"שׁ וְהַמָּרְדְּכַי פ' ג' שֶׁאָכְלוּ וְטוּר) וְכֵן נוֹהֲגִין וְאֵין לְשַׁנּוֹת; וְחֵרֵשׁ וְשׁוֹטֶה אִם מְכַוְּנִים וּמְבִינִים מִצְטָרְפִין לְזִמּוּן, אַף עַל פִּי שֶׁאֵין הַחֵרֵשׁ שׁוֹמֵעַ הַבְּרָכָה (מַהֲרִי"ל).
10 A minor that has reached the age of understanding that he is praying to God can be included for the zimun for 3 and 10. Some say that a child cannot be included in a zimun until he reaches the age of thirteen and then he is assumed to be an adult who has produced two hairs. (Rosh and Mordechai Perek Shlosha Sheachlu and Tur) This is the custom and one should not deviate from it. Someone deaf or insane may be included in a zimun if he can concentrate and focus even though the deaf person cannot hear the beracha (Mahril)
יא מִי שֶׁנִּדּוּהוּ עַל עֲבֵרָה, אֵין מְזַמְּנִין עָלָיו.
11 One whom they excommunicated due to a sin is not included in a zimmun.