According to the TSA and most international aviation authorities in 2026, vitamins and supplements in solid form (pills, capsules, or gummies) do not have to be in their original bottles for domestic travel within the United States. You are permitted to use weekly pill organizers or small plastic bags to save space in your carry-on or checked luggage. However, if you are traveling with liquid vitamins larger than 3.4 oz (100ml), they must be in their original, clearly labeled packaging to qualify for a medical exception, or they will be confiscated at the checkpoint. For international travel, it is a strongly recommended "peer-to-peer" best practice to keep everything in its original container. Customs officers in foreign countries may be far stricter than the TSA, and an unlabeled bag of white powder or mysterious green pills can lead to extensive delays, questioning, or even seizure if the local authorities cannot easily verify that the substances are legal.