Marketplace Fairness Act of 2013 - Authorizes each member state under the Streamlined Sales and Use Tax Agreement (the multistate agreement for the administration and collection of sales and use taxes adopted on November 12, 2002) to require all sellers not qualifying for a small-seller exception (applicable to sellers with annual gross receipts in total U.S. remote sales not exceeding $1 million) to collect and remit sales and use taxes with respect to remote sales under provisions of the Agreement, but only if such Agreement includes minimum simplification requirements relating to the administration of the tax, audits, and streamlined filing. Defines "remote sale" as a sale of goods or services into a state in which the seller would not legally be required to pay, collect, or remit state or local sales and use taxes unless provided by this Act.