Does tea require a Hechsher for Pesach?
Tea is considered one of the oldest and favored drinks in many societies and many people enjoy drinking a hot cup of tea on Pesach. This especially applies this year, due to the coronavirus outbreak, in which many believe that drinking hot tea, or any hot drink, helps battle the spread of the Coronavirus. [To note, however, that we have been unable to confirm this advice from any authoritative practitioner, health ministry, or major news outlet, and the above does not come to endorse it as medical advice.]
Halachic background of tea drinking on Pesach:
The Halachic debate in previous times: Already with the onset of the European tea drinking in the 16th century, we find that Jewish communities throughout Europe avoided drinking tea on Pesach due to suspicion that the tea bags were recycled after their initial use and resold to the market. Now, since it is possible that the initial use involved Chametz [such as if biscuits were dipped into the hot tea], therefore the custom became to avoid drinking tea on Pesach. Accordingly, some Poskim discouraged the drinking of tea on Pesach, and advised everyone to avoid it. Nonetheless, some Poskim defend the drinking of tea on Pesach if one knows that it was purchased from dealers who market the tea directly from their area of growth, and it retains its original packaging. Likewise, the experts claim that it is Kosher for Pesach, as they can tell the difference between recycled tea, versus tea that has never yet been cooked. The following is the custom relevant for today:
The custom today: In today’s times, there is no longer any substantial worry that tea manufacturers will recycle the tea bags for later marketing and therefore the above-mentioned worry that caused people to avoid tea on Pesach is no longer relevant. There is also no substantial worry that the drying and manufacturing of the leaves contain any non-Kosher or Chametz ingredients, and hence in general it does not require a Hashgacha neither throughout the year or for Pesach, as will be explained below in B. In addition to the above, there exists tea’s with Hashgacha’s for Pesach which explicitly verify that it contains no worries of Chametz infiltration, and hence many Jews no longer avoid drinking tea on Pesach. Nonetheless, due to the above-said old age custom of Ashkenazi Jewry, some are accustomed even today not to drink tea on Pesach, even if it contains a Hashgacha, in living with the phrase “Al Titosh Toras Imecha.” The following is the Lubavitch custom regarding this matter:
The custom in Lubavitch: It was customary in Lubavitch to drink tea on Pesach. The Rebbe Raytaz was accustomed to drink tea on Erev Pesach after Mincha. However, the Rebbe did not drink tea on Pesach and asked for it to be sold together with the items sold to the gentile. [It is unclear as to the reason for the Rebbe’s avoidance.]
The practical ruling
Plain teas [black tea, green tea, etc, not decaffeinated, and not flavored]: Ideally, plain teas do not require a Hashgacha for Pesach as they do not contain any known worry of Chametz infiltration. Nonetheless, it is proper to try to purchase tea that contains a Hashgacha for Pesach. If plain tea with a Hashgacha for Pesach is not available in one’s area, then one may be lenient to use plain tea without a Hashgacha. Nonetheless, it is better to purchase a package of plain tea leaves than to purchase the tea bags, as the bags may contain a suspicion of starch. Alternatively, one can purchase the tea bags and check the bag for starch through an iodine solution, as explained here. [We checked the plain yellow tea bags of Lipton and the bag and string came out negative, although the paper that holds the string and contains the yellow Lipton logo came out positive and thus contains starch. Accordingly, one should not purchase this brand of tea for Pesach, or is to alternatively cut off the paper before use.] In the event that the tea purchased does not contain a Hashgacha, it is advisable to make a large quantity of tea essence before Pesach, and use it throughout Pesach, rather than to initially make the tea on Pesach.
Scented or flavored teas [herbal and non-herbal], decaffeinated teas, and instant teas: All scented teas, herbal teas, decaffeinated teas, and instant tea, must have a Hashgacha for Pesach.
 Shvus Yaakov 2:5 “I heard many people avoid drinking tea on Pesach as there is a worry of trickery, that the sellers recycle the used tea bags and dry them and re-sell them to the market. So I have heard from a good multitude of Kosher Jews, and therefore every person is to distance himself from tea drinking over pesach, as on Pesach one needs extra distancing”, brought in Birkeiy Yosef 453:4, Shaareiy Teshuvah 453:1, Kaf Hachaim 453:23; Kaf Hachaim ibid concludes after bringing a story in which a large tea manufacturer was discovered to be recycling the used tea bags, that one is to avoid drinking tea on Pesach unless it was properly researched to have not been recycled.
 Shaareiy Teshuvah 453:1; See Ikarei Hadaat 18:34, brought in Kaf Hachaim ibid, that so long as the tea remains in its initial packaging from its area of growth, people are accustomed to buy it for Pesach, as only the local tea merchants are suspected for recycling the tea bags; Sdei Chemed 4:17 in name of Beis Meir 447:5 that it is permitted to drink tea, and its like a permitted matter which others have accustomed to treat as a prohibition, and the Sdei Chemed concludes that there is no worry at all to drink tea on Pesach
 See Likkutei Maharich 21b; Shevach Hapesach p. 263; Raza Deuvda p. 123; Hagadas Lelov p. 8
 See Halekach Vehalibuv 2:216; Otzer Minhagei Chabad 7, p. 72; Rav Eli Landa Shlita relates that in Lubavitch they explicitly would drink tea on Pesach, although would purchase it from a known and trustworthy company which would not add coloring to it. He states that he never heard of any issue with the plain unflavored tea [although he himself stopped drinking tea on Pesach after discovering that it goes through a fermenting and steaming process, nonetheless he does not rule this way for others and says that it’s a personal Chumra, as instead he simply drinks coffee that he makes at home].
 Toras Menachem 1:22 footnote 4; Yimei Bereishis p. 130
 Hiskashrus Vayikra 5772 and reply of Rav Groner
 The OU and CRC both write that plain tea may be consumed on Pesach without any Hashgacha; The OU writes as follows https://oukosher.org/passover/guidelines/food-items/coffee/ “Unflavored tea bags (including black, white, and green) are acceptable for Pesach without special supervision. Decaffeinated and instant teas require special Passover certification unless listed as approved with a regular OU symbol.”; The CRC writes as follows  http://www.crcweb.org/kosher_articles/coffee_and_tea_pesach.php “Black, green, white, yellow, oolong, and jasmine tea are all inherently kosher for Pesach, but the issues of decaffeination and flavoring apply to tea in the same way that they apply to coffee. For that reason all decaffeinated tea and all flavored tea (which includes most herbal teas) should only be used on Pesach if they bear an appropriate Pesach certification.”; The Chaf Kei however writes that it is recommended for it to contain a Hashgacha, as the ways of manufacturing can change with time.
The position of the Vaad Hakashrus Eida Hachareidis: The Madrich of the Eida Hachareidis does not make any mention as to the consumption of tea and if it contains a Kashrus worry. However, in the Madrich for 1977 they stated that they recently heard of new ways of manufacturing the tea and therefore that year they refused to give a Hashgacha until further verification. Practically, after speaking with a member of the Vaad Hakashrus, he advised as follows: Of course, initially one should purchase tea with a Hashgacha for Pesach. However, if not available, then it is better to purchase plain tea leaves rather than tea bags [due to the worry of starch] and make the essence before Pesach. [This is no the official policy of the Eida Hachareidis, as they do not have an official policy on tea, and was simply the advice of an official member of their Vaad Hakashrus.]
 All the above mentioned Hashgacha organizations