May one squeeze fruits on Yom Tov?
In all cases that squeezing is permitted on Shabbos it is likewise permitted on Yom Tov. [See our Sefer “The Laws of Shabbos Volume 2-The Laws of Squeezing fruits” for the full details of the laws of squeezing on Shabbos and a complete list of which fruits are forbidden to be squeezed on Shabbos.”] In this Halacha we will focus on if there are any leniencies of squeezing afforded to Yom Tov of which we are stringent on Shabbos.
Squeezing into food: It is permitted to squeeze juice into solid foods on Yom Tov just like on Shabbos.
Squeezing to drink its juice: It is Rabbinically forbidden to squeeze juice for drinking purposes on Yom Tov. Furthermore, any matter which was Rabbinically prohibited on Shabbos due to that one may come to transgress the squeezing prohibition, is likewise prohibited on Yom Tov. [Accordingly, it follows the same laws as Shabbos for all matters, and whatever is forbidden to be squeezed on Shabbos is likewise forbidden to be squeezed on Yom Tov.] It is forbidden to squeeze even with an irregularity. It is forbidden to perform squeeze on Yom Tov even if it was not possible to perform it before Yom Tov. [However, some Poskim question whether it is nevertheless permitted to squeeze with intent to drink immediately. Likewise, some Poskim question whether it is nevertheless permitted to squeeze to drink that day if the taste of the juice would dissipate if squeezed before Yom Tov. Accordingly, some Poskim rule that if he is very thirsty, then on Yom Tov one may hand squeeze fruits to be drunk immediately, using an irregularity, such as one’s left had]. Furthermore, some Poskim rule that in a situation that one could not squeeze the juice before Yom Tov, being that he had no more room in his fridge, or that he only drinks freshly squeezed juice, then he may squeeze them with an irregularity. However, according to the Setimas Haposkim, the implied ruling of Admur, these allowances do not apply, and it is never permitted on Yom Tov to squeeze fruits for the sake of drinking the juice just like is the ruling on Shabbos. Practically, many of today’s Poskim conclude to be stringent and not to rely on any of the allowances brought above.]
One may not squeeze fruits on Yom Tov to drink their juice just as is the law on Shabbos. One should not rely on the leniencies suggested by some Poskim who permit squeezing under certain circumstances, and is rather to avoid squeezing any fruit for drinking its juice just as is the law on Shabbos, especially according to the rulings of Admur.
May one squeeze lemon juice on Yom Tov for the sake of making punch or lemonade?
 See SSH”K 5:1; Nitei Gavriel 4:1-3; Piskeiy Teshuvos 495:7; Yom Tov Kehilchaso 10:2
 Admur 495:2 that squeezing it is Biblically permitted; Admur 495:9 that it is nevertheless Rabbinically forbidden; Michaber 495:1-2 “All Melacha that is forbidden on Shabbos is likewise forbidden on Yom Tov, except for food related Melachos. (495:1) However, harvesting, grinding, squeezing, and trapping, even though they are food related the Sages prohibited them. (495:2)”; Beitza 3a; Rosh and Ran Beitza chapter 3; Maggid Mishneh in opinion of Rambam Yom Tov 1; Tur in name of Riy; M”A 495:4; Taz 495:2; Kaf Hachaim 495:20;
Other opinions: Some Poskim rule that such Melacha is Biblically forbidden to be done on Yom Tov. [Ran according to Yerushalmi; Rashba; Rashal, brought in M”A 495:4 and Taz 495:2 and Elya Raba 495:9, and M”B 495:13;Semag L.S. 75; See Kaf Hachaim 495:24] Other Poskim rule that squeezing is permitted on Yom Tov. [Bahag; See Rashal 1:39; Tzelach Beitza ibid]
 The reason: As squeezing is normally done for many days’ worth and the Sages prohibited one from doing food related Melacha that is normally done for many days’ worth in order so one does not come to abstain from Simchas Yom Tov due to being overinvolved with food preparations. The Sages suspected that if these Melachos were to be allowed, one would trouble himself on Yom Tov also for the sake of the weekday, being that it is common for these Melachos to be done with a quantity of food that will last many days, and he will thus have no time for involvement in Simchas Yom Tov. [Admur 495:9 and 495:7-8; Rambam ibid as explained in Maggid Mishneh]
 Chayeh Adam 81:7
 Admur ibid; Admur 328:40 and 505:8 regarding sucking milk from cow that although it is an irregularity, it is only allowed if there is no food available to squeeze into, and one is in pain; Olas Shabbos 495:2; Elya Raba 495:9; P”M 495 A”A 4; M”B 495:13; Kaf Hachaim 495:25
 Admur ibid; Kaf Hachaim 495:25
 P”M 505 A”A 3 questions whether squeezing for right away use is permitted, as M”A 505:7 and Taz 505:4 imply that it is permitted, although he concludes with a Tzaruch Iyun
 SSH”K 5:1 in footnote 1; Piskeiy Teshuvos ibid; See Admur 504:1 who gives a similar allowance regarding grinding with an irregularity if the taste would dissipate if done before Yom Tov; See Ben Ish Chaoy Yisro 1:6
 Chelkas Yaakov 2:85 and 212; Shearim Hametzuyanim Behalacha 98:7
 Meaning without using a hand squeezer, but rather by pressing on it with ones hands. [Piskeiy Teshuvos ibid; Nitei Gavriel 4:3 footnote 9]
 This allowance especially applies to lemons in which there are Poskim which rule that even on Shabbos it is permitted. [Chelkas Yaakov ibid]
 Beir Moshe 8:224; Shearim Hametzuyanim Behalacha 2 98:7; Chelkas Yaakov 2:85; Piskeiy Teshuvos ibid; So rule regarding squeezing almond milk: Peri Chadash 495; Mor Uketzia 495; P”M 495 A”A 3; M”B ibid; Kaf Hachaim 495:15; See SSH”K 5:1 in footnote 1
 Regarding the allowance of the Beir Moshe Tzarich Iyun Gadol on how he took the allowance of grinding herbs of short use and applies it also to squeezing fruits, when from the Shulchan Aruch’s rulings no such allowance seems to apply by fruits.
 Admur ibid forbids even with an irregularity and if could not do the day before, and Setimas Admur negates the above Heterim of drinking right away, as well as his explanation of the allowance to suckle milk from a cow on Yom Tov completely negates the reasonings of leniency that the Poskim suggested above, as Admur did not suffice with allowing it simply because it could not have been done Erev Yom Tov and is an irregularity and is drunk right away, but also adds that it is a case of pain, and that there is no food available. This negates the basis of the leniency of the Chelkas Yaakov ibid whose allowance is based on his understanding of the Heter to suckle milk of a cow when one is thirsty.
 Rav SZ”A in SSH”K 5 footnote 1 negates these allowances and rules plainly that it is never allowed; Hilchos Hamoadim 12:1; Yom Tov Kehilchaso 10:2 and Miluim, 3; 2nd opinion in Piskeiy Teshuvos ibid; Nitei Gavriel 4:12 that there is never an allowance even through an irregularity and even if its taste would dissipate if done the day before, and even for right away use
 Nitei Gavriel 4:4
 As even on Shabbos many Poskim are lenient, including Admur; See our corresponding Sefer The laws of Shabbos Volume 2-The laws of squeezing” under the laws of lemons for the full details of this subject and why lemon squeezing may be subject to additional leniencies.