What is Spiffs?
If you received a 1099-Misc for income you earned, then you more often than not should report it on a Schedule -C. When you report on a Schedule C, yes, you would claim expenses incurred to earn the income.
Spiffs are money you receive from manufactures on a 1099-Misc. These are common for guys that sell cars, but mine come from selling certain brands of food. You mark "manufacturers incentive" on the 1099-Misc in Turbo tax. From what I understand this income doesn't require you to file a schedule C. I'm just trying to find out why you wouldn't want to so you could claim expenses. Thank you.
Sch C income is subject to Medicare and Social Security tax along with the income tax. Filing the Sch C allows you to deduct the expenses associated with the income.
Self-Employment tax (Scheduled SE) is automatically generated if a person has $400 or more of net profit from self-employment. You pay 15.3% SE tax on 92.35% of your Net Profit greater than $400. The 15.3% self-employed SE Tax is to pay both the employer part and employee part of Social Security and Medicare. So you get social security credit for it when you retire.