French Main Physical Person Tax Liabilities

In the case of a married couple, where one of the spouses is under 65 years of age, but the other at least 65 years, then the couple are treated for tax purposes as though they were both 65+. The same principle applies where one of the spouses has a serious disabilty. [2]
If your income is higher than any of the threshold figures in the table, but you were entitled to an income tax credit (say, for energy conservation works), then the value of the credit would be set against the amount of tax for which you were liable. Even if you paid no income tax, then a tax credit would earn you a cheque from the French taxman. [2]
In addition, a discount mechanism operates for those who pay little by way of income tax.
So for 2014 (for income earned in 2013) you are liable to pay tax of less than €1,016, a rebate is payable to you on a formula basis that lowers the amount you would actually be required to pay. The calculation is a discount equal to the difference between €508 and half of the income tax to which you are liable. [2]
Example:
Income tax before discount = €650
Discount = €508 - €650/2 = €183
Income tax after discount = €650 - €183 = €467
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