While being used for their original contents, do food storage containers (even glass or metal) require tevilah? For example, if one has a glass bottle of salad dressing that he uses for weeks until it is finished, does it require tevilah because it is used more than once (i.e., for more than one meal?)
It does not need tevila according to most poskim. There are a number of reasons for this. Most poskim consider the bottle, as a one-time storage container, and the food is there only until it is finished. Among the reason given are, that since it is meant to throw out, it is not considered a kli, therefore it doesn’t need tevila. Even though it is being used for storage now, we only have to tovel utensils that we are using for eating or processing the food for eating but not for storage, (at least according to some poskim). Others say that just keeping the food in the jar and not throwing it out is not considered “using” the bottle, therefore it doesn’t need tevila. ther
Igros Moshe Y:D 2-40, Tzitz Eliezer 8-26(2), Minchas Shlomo 2-66(10), Ohr L’tzion 1-24, Machazeh Eliyahu 1-100-3, 101, M’bais Levi 15 pg. 80, Maharil Diskin (Kuntris Acharon) siman 5-136, Yabia Omer 7 Y:D 9-3.
Others say that since the container is being thrown out after its use, the person never really meant to buy it from the gentile, rather only the food and the bottle gets discarded. See Sridei Aish 2-29, Chelkas Yackov Y:D 42, Mishne Halachos 4-107.