Recycling of PET Bottles is the activity whereby bottles made out of PET (polyethylene) plastic are collected and processed in order to reuse the material out of which they are made. In the United States, PET plastics are coded with the number 1 which is found inside the universal recycling symbol, usually located on the bottom of the container.

PET is used as a raw material for making packaging materials such as bottles and containers for packaging a wide range of food products and other consumer goods. Examples include milk, mineral water, soft drinks, alcoholic beverages, detergents, cosmetics, pharmaceutical products, edible oils, etc. PET is one of the most common consumer plastics used.

The empty PET packaging is discarded by the consumer after use and becomes PET waste. In the recycling industry, this is referred to as "post-consumer PET." Many local governments and waste collection agencies have started to collect post-consumer PET separately from other household waste. The collected post-consumer PET is taken to recycling centres known as Material Recovery Facilities (MRF) where it is sorted and separated from other materials such as metal, objects made out of other plastics such as PVC, polyethylene, polypropylene, drink cartons, and anything else which is not made out of PET.

Post-consumer PET is sometimes also sorted into different colour fractions: transparent or uncoloured PET, blue and green coloured PET, and the remainder into a mixed colours fraction. The emergence of new colors (such as amber for plastic beer bottles) further complicate the sorting process for the recycling industry.

This sorted post-consumer PET waste is crushed and pressed into bales, which are offered for sale to recycling companies. Transparent post-consumer PET attracts higher sales prices compared to the blue and green fractions. The mixed colour fraction is the least valuable.

Recycling companies will further treat the post-consumer PET by shredding the material into small fragments. These fragments still contain residues of the original content, shredded paper labels and plastic caps. These are removed by different processes, resulting in pure PET fragments, or "PET flakes". PET flakes are used as the raw material for making new PET bottles or other applications.