Tax time isn't something that we generally cheer about, but knowing that you're not overpaying the government might make the whole thing a little more pleasant. Kiplinger's [1] put together a list of the 13 most-overlooked tax deductions [2] — check them out to make sure you're deducting everything you can!

1. State sales tax: This is mostly beneficial if your state doesn't impose an income tax. Figure out your deduction with the IRS sales tax deduction calculator [3].
2. $250 educators' expenses: If you work in a classroom and spent money on books and supplies last year, you can deduct up to $250 for these purchases.
3. College tuition: If you forked up college tuition payments last year for yourself, your spouse, or a dependent then you may be able to deduct up to $4,000.
4. Student loan interest paid by Mom and Dad: If your parents paid student loan interest on your behalf and they don't claim you as a dependent, you can deduct up to $2,500 for any interest paid by your parents.
5. Out-of-pocket charitable contributions: For example, ingredients for bake sales or stamps you bought to send out fundraising letters.
6. Moving expense to take first job: If you moved more than 50 miles to live closer to your first job, you can deduct moving costs including 20 cents a mile, parking fees, and tolls — even if you drive your own car.

There are seven more on the list, so just

7. Military reservists travel expenses: You may be eligible to deduct travel expenses to drills or meetings.
8. Child-care credit: You can apply this credit to $6,000 of expenses for two or more children. If you run the maximum $5,000 through a reimbursement plan at work but your expenses exceed that amount, you can claim the credit on that extra $1,000, which would cut your tax bill by at least $200!
9. Estate tax on income in respect of a decedent: If you inherited an IRA, you can take an income-tax deduction for the estate tax paid on the IRA.
10. State tax you paid last Spring: Include any taxes you paid for your state return last tax season in this year's state-tax deduction.
11. Refinancing points: If you refinance a mortgage the points are deducted over the life of the loan.
12. Reinvested dividends: You can deduct every cent of reinvested dividends, and forgetting to include them means you're paying too much in taxes.
13. Jury pay paid to employer: If you served jury duty last year, look for the line on your tax forms to include this deduction.

Source [4]