Middle-class Americans already pay an average of 43.12% in taxes, according to the non-partisan Tax Foundation.
Money Morning Chief Investment Strategist Keith Fitz-Gerald detailed the possible increase in the tax tab, citing data from FOX Business Network's expert on consumer and personal finance, Gerri Willis.
Absent a fiscal cliff deal, the mean middle class federal tax rate would climb from 25% to 28%, as Bush-era tax cuts expire in 2013. Payroll taxes would rise from 13.3% to 15.3%.
"Keep in mind that doesn't include state income tax hikes, city or county taxes, many of which are on the rise no matter where you live, thanks to decades of poor fiscal management," Fitz-Gerald said.
Add in state taxes, which average 4.82%, and the middle-class tax burden would average a whopping 48%.
As Fitz-Gerald put it, the possible tax increases amount to "an assault on the middle class."