<prompt> Human: My wife and I just worked on our taxes in TurboTax and to our surprise, we owe 8,000 in federal taxes.Last year, we had 155,145 in combined income, 28,000 in deductions, and a total of 20,000 was withheld, and we got a 1,000 refund.This year, we have 204,864 in combined income, about 34,000 in deductions, and about 27,000 was withheld. TurboTax says we owe about 8,000.The best we can figure, we didnt update our W4s this year, even though we knew our income would go up. My wife got a job about half way through the year in 2014. We didnt know about the multiple earners worksheet and thought just the 2 allowances was correct for both of us. I guess we needed to indicate extra to be withheld?Weve been aggressively paying off about 160k in student loans over the last few years and are getting close to being done, but not having anticipated such a high tax bill, we dont have near that much cash set aside for emergencies.Obviously we can pause loan payments and save very aggressively for the next two months and we should be able to save up the 8,000. But, its still quite a blow to our morale. So, two questions:1. I know this is a generic question, but is there anything we can do to help lower what we owe? Most of our deductions are from charitable giving and some work related expenses.2. Can you point us to some resources for better understanding our W4s so we can avoid this issue in the future?Thanks!  <response>: File your 2015 federal return on time.Fix your federal withholding tomorrow.If you cant afford to pay in full when you file, send the largest amount you can comfortably afford on or before 4182016. Even if its 50, thats 50 not subject to penalties and interest.Assuming you e-file timely, you will receive your first notice in the third week of May. The balance due on the notice generally has your unpaid tax, plus assessments of penalties and interest.The most common penalties are the Failure To File FTF only if you file late with a balance due, and Failure To Pay FTP. The FTP accrues until the tax liability is paid at 0.5 of the tax per month or part of a month. The IRS interest rate is currently 3 per year, compounded daily on the unpaid tax and penalties. The interest rate can be increased or decreased on a quarterly basis.If you can find a way to pay the balance on your notice by the due date, you are done.The short-term payment plan can be up to 120 days, and it is called a Full Payment Agreement. With this plan, there is no requirement for a fixed monthly payment. The Service calculates the balance due out to 120 days from the request date, and you agree to pay in full by that due date. During the 120 days you could make one payment or 100 payments. There is no fee to request this agreement.You can set up new payment plans at IRS.gov Online payment Agreement Have a copy of your notice handy when you access the system.You can call 1-800-829-0922 M -F 7am - 7pm local time and speak with a representative. They will ask some verification questions, research your account, and provide your payment options.You can visit your local Taxpayer Assistance Center TAC for face-to-face help with an IA. Please note: many TACs now require appointments. 