In the US quarterly taxes are generally used if you are a contract worker and you do not get consistent weekly, bi-weekly, or monthly pay checks. In this case you have to estimate tax witholdings quarterly, because the government wants your money as you earn it so they can get interest instead of you!
If you fail to file quarterly tax returns or you grossly underestimate the quarterly tax witheld at the end of the tax year the government (here in the US) will hit you with a hefty penalty.
I know this first hand because the first year I was a contract engineer I did not file quarterly taxes so come April 15th (the black day taxes are due in the US) I went to my tax guy and said well I made $180,000 for the year. He asked how much had I sent in for quarterly taxes and I replied nothing why? He then turned pale and asked - Do you drink? I said no. He replied you may want to start after I tell you what you are going to owe in penalties for not sending in quarterly estimated witholdings!
In the end I paid the 30% or so of normal taxes and then had to pay another nearly 40% in penalties for a total tax of around 70%! So I worked an entire year and got to keep 30% of what I earned. Of course I did not have 70% of my earning saved, so I had to give the bastards every dime I had and then get on a installment plan to pay the rest with yet more interest! It took me almost 2 years to pay the taxes and in the end I payed the bastards more then I made for that entire year I did not send in quarter returns! I made $180k for that year and in the end paid the ****ing government over $230k in taxes and penalties and interest for that years tax!
"If I have seen further it is by standing on the shoulders of giants." Sir Isaac Newton, 1675
Last edited by ctbram; 28-05-2012 at 02:30 PM.