Establishments are allowed to use up stock on hand if they seek out and obtain approval of an exemption, which will require proof of a purchase date and ideally prior to November 27, 2019 when the ordinance originally passed.
Alternatively, chain stores with outlets outside of Charleston can consider shipping their bag inventory to those outlets. Smaller stores with stocks likely to last a while will probably find their customers wondering why they are still using plastic bags. Faced with customer concern, they may choose to donate their remaining stock to a food bank.
If you can't reuse them or donate them, please bring them to a grocery store that accepts plastic bags for recycling. Please note, plastic bags contaminate Charleston County's Recycling Centers, so please do NOT place them in your blue carts.