Main Street Fair Competition Act of 1988

Main Street Fair Competition Act of 1988 - Empowers any State and the District of Columbia to require a person to collect a State sales tax imposed with respect to the sale of tangible personal property if: (1) the destination of sale is in such State; and (2) the person engages in regular or systematic soliciting of sales in the State and has, within a specified one-year period, gross receipts from the sale of such property that exceed either $750,000 within the State or $15,000,000 nationally.

Sets forth requirements under which local sales taxes may be collected as a component of State sales tax.

Prohibits a State from requiring: (1) any person who collects a State sales tax to make an accounting for the receipts of such tax on the basis of the geographical location at which the taxable transaction occurs; or (2) collection of sales tax under this Act unless the State has available a toll-free telephone service to provide potential collectors with information relating to liability for and collection of State sales tax.

Limits a State's authority in connection with tax return filing and payment frequency requirements.

Applies relevant State law to persons required to collect State sales tax under this Act.