Siman 694
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 חַיָּב כָּל אָדָם לִתֵּן לְפָחוֹת שְׁתֵּי מַתָּנוֹת לִשְׁנֵי עֲנִיִּים. הַגָּה: יֵשׁ אוֹמְרִים שֶׁיֵּשׁ לִתֵּן קֹדֶם פּוּרִים מַחֲצִית מִן הַמַּטְבֵּעַ הַקָּבוּעַ בְּאוֹתוֹ מָקוֹם וּבְאוֹתוֹ זְמַן, זֵכֶר לְמַחֲצִית הַשֶּׁקֶל שֶׁהָיוּ נוֹתְנִין בְּאֲדָר; וּמֵאַחַר שֶׁשְּׁלֹשָׁה פְּעָמִים כָּתוּב תְּרוּמָה בַּפָּרָשָׁה, יֵשׁ לִתֵּן שְׁלשָׁה (מָרְדְּכַי רֵישׁ פ"ק דִּמְגִלָּה); וְיֵשׁ לִתְּנוֹ בְּלֵיל פּוּרִים קֹדֶם שֶׁמִּתְפַּלְּלִים מִנְחָה (מַהֲרִי"ל), וְכֵן נוֹהֲגִין בְּכָל מְדִינוֹת אֵלּוּ; וְיֵשׁ לִתֵּן ג' חֲצָאִים גְּדוֹלִים בִּמְדִינוֹת אֵלּוּ, כִּי אֵין מַטְבֵּעַ שֶׁשֵּׁם מַחֲצִית עָלֶיהָ מִלְּבַד זוֹ; וּבִמְדִינוֹת אוסטריי"ף יִתְּנוּ ג' חֵצִי וויינ"ר, שֶׁנִּקְרְאוּ גַּם כֵּן מַחֲצִית, וְכֵן לְכָל מְדִינָה וּמְדִינָה; וְאֵין חַיָּב לִתְּנוֹ רַק מִי שֶׁהוּא מִבֶּן עֶשְׂרִים וּלְמַעְלָה, וְיֵשׁ אוֹמְרִים שֶׁנּוֹתְנִים מַחֲצִית הַשֶּׁקֶל לִצְדָקָה מִלְּבַד ג' מַחֲצִית אֵלּוּ, וְאֵין נוֹהֲגִין כֵּן.
1 The law as regards Purim money for the poor. Containing 4 paragraphs: All people must give at least two gifts to two poor people. Rema: Some say that there is [support] to give prior to Purim a half-coin that is established in that place and in that time as a memorial to the Shekel half-coin that they would give in Adar. And since "terumah [tithe]" is written three times in that portion, there is [support] to give three [half-coins] (Mordechai, beginning of the first chapter of Yoma). And there is [support] to give on the night of Purim prior to praying the Mincha prayer (Maharil), and such is the custom in all these provinces. And there is [support] to give 3 half-coins of the bigger [coins] in these provinces, for there is no coin that is only half beside for [the bigger coin], and in Austria, they would give 3 half-coins of Vienners, which were also called "halfs". And so it is for each province. And only someone who is 20 or older is obligated to give. And some say that one should give the half-shekel to charity in addition to these three halves, but that is not the custom.
ב אֵין מְשַׁנִּין מָעוֹת פּוּרִים לִצְדָקָה אַחֶרֶת. הַגָּה: וְדַוְקָא הַגַּבָּאִים (מָרְדְּכַי פ"ק דְּבָבָא בַּתְרָא), אֲבָל הֶעָנִי יָכוֹל לַעֲשׂוֹת בּוֹ מַה שֶּׁיִּרְצֶה.
2 One should not change money that was given to the poor for Purim for other Tzedakah causes. Rema: This is referring to the collectors of the money (Mordechai) — the poor can do whatever they want.
ג אֵין מְדַקְדְּקִים בְּמָעוֹת פּוּרִים אֶלָּא כָּל מִי שֶׁפּוֹשֵׁט יָדוֹ לִטֹּל נוֹתְנִים לוֹ; וּבְמָקוֹם שֶׁנָּהֲגוּ לִתֵּן אַף לְעַכּוּ"ם, נוֹתְנִים.
3 One is not exacting with their money on Purim. Rather, one should give to anyone who extends their hands. And in places where they have a custom to give even to non-Jews - one should give.
ד בְּמָקוֹם שֶׁאֵין עֲנִיִּים, יָכוֹל לְעַכֵּב מָעוֹת פּוּרִים שֶׁלּוֹ לְעַצְמוֹ וְנוֹתְנָם בַּמָּקוֹם שֶׁיִּרְצֶה.
4 In a place that does not have poor people one may delay his Purim money to himself and give it in a place where he wants.