Paying a Fair Share Act of 2013 - Amends the Internal Revenue Code to require an individual taxpayer whose adjusted gross income exceeds $1 million to pay a minimum tax rate of 30% of the excess of the taxpayer's adjusted gross income over the taxpayer's modified charitable contribution deduction for the taxable year (tentative fair share tax). Establishes the amount of such tax as the excess (if any) of the tentative fair share tax over the excess of: (1) the sum of the taxpayer's regular tax liability, the alternative minimum tax (AMT) amount, and the payroll tax for the taxable year; over (2) certain tax credits. Provides for a phase-in of such tax. Requires an inflation adjustment to the $1 million income threshold for taxable years beginning after 2014.

Expresses the sense of the House of Representatives that Congress should enact tax reform that repeals unfair and unnecessary tax loopholes and expenditures, simplifies the tax system, and makes sure that the wealthiest taxpayers pay a fair share of taxes.