I got an enlistment bonus of 5,000 dollars that i got once i got out of my MOS school and it got taxed and i was told i was able to get that money back on my taxes

[Hal_Al · Accepted solution]

You did not "already pay tax". What you paid was only withholding, an estimate of the tax due. No piece of income is taxed individually. All your income, including enlistment bonuses, is added together at tax filing time. The tax is calculated on that total (after adjustments, deductions, exemptions and credits). Then total  withholding is subtracted to determine if you owe more or get a refund.
By law, lump sum payments, like a bonus  are withheld at a higher rate than ordinary wages. So, there is a good chance you'll get most (but not all) of that back.

[Critter]

You must file a tax return to get a refund of any over withheld taxes ... however since that bonus is added to your other annual income (and not filed by itself) you may not get all of that withholding back.