Cash on delivery (COD)
An online order the customer pays for when it arrives, rather than when they place it.
COD lets customers who do not trust a new seller, or do not pay online, still order. The cost is that the seller has spent on the product and the shipping before knowing the customer will accept it, and refused COD parcels come back at the seller's expense.
Many small sellers keep COD but confirm each order first, or ask for a small advance on it.
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See also: UPI for business