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Refund policies from California Civil Code 1723
(a) Every retail seller which sells goods to the public in this state that has a policy as to any of those goods of not giving full cash or credit refunds, or of not allowing equal exchanges, or any combination thereof, for at least seven days following purchase of the goods if they are returned and proof of their purchase is presented, shall conspicuously display that policy either on signs posted at each cash register and sales counter, at each public entrance, on tags attached to each item sold under that policy, or on the retail seller's order forms, if any. This display shall state the store's policy, including, but not limited to, whether cash refund, store credit, or exchanges will be given for the full amount of the purchase price; the applicable time period; the types of merchandise which are covered by the policy; and any other conditions which govern the refund, credit, or exchange of merchandise.
(b) This section does not apply to food, plants, flowers, perishable goods, goods marked "as is," "no returns accepted," "all sales final," or with similar language, goods used or damaged after purchase, customized goods received as ordered, goods not returned with their original package, and goods which cannot be resold due to health considerations.
(1) Any retail store which violates this section shall be liable to the buyer for the amount of the purchase if the buyer returns, or attempts to return, the purchased goods on or before the 30th day after their purchase.
(2) Violations of this section shall be subject to the remedies provided in the Consumers Legal Remedies Act (Title 1.5 (commencing with Section 1750) of Part 4).
(3) The duties, rights, and remedies provided in this section are in addition to any other duties, rights, and remedies provided by state law.
Department Publications: DCA Fact Sheet: Refunds and Display of Refund Policy