In some states, cities, counties and school districts have an income tax, in addition to the state. If you work in a city with a tax, your employer is required to withhold city tax. In most cases, you don't need to file a city tax return (they already got their money). If you itemized deductions, on the federal, the box 19 amount is usually deductible. You pay stubs may have the name of the city.
Some times, you employer might withhold tax for you residence city (this is less likely than work city withholding).
