Longman Dictionary of Contemporary English
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In the UK tax system, personal allowance is the threshold above which income tax is levied on an individual's income. A person who receives less than his/her personal allowance in taxable income (such as earnings and some benefits) in a given tax year does not pay income tax; otherwise, tax must be paid according to how much is earned above this level. Certain residents are entitled to a larger personal allowance than others. Such groups include the over 65s (followed by an increased allowance for over 75s), blind people, and married couples where at least one person in the marriage (or civil partnership) was born before 6 April 1935.
Usage examples of "personal allowance".
You are traveling in Sybarite class with a personal allowance suitable to an heiress of independent means.
I always fill up the extra comers of my personal allowance with silly clothes- You can get necessities back home.
I had a tiny personal allowance, and it was really no hardship to give it up for such a cause, since I had nowhere to spend it.
I'm sure you're ignorant of this, but at that rate, your money, compounded, less even an exorbitant personal allowance, will double approximately every three years, particularly when you don't pay any taxes.
If you don't treat him with respect I will curtail your personal allowance.