I used to be a contractor (1099) in 2014, but have been a W-2 employee all of 2015 and 2016, I work for a startup that I am not the owner of, they pay me as a w2 employee.
In 2015, I maxed out my Solo 401(k) through Vanguard. I was wondering if I can use my Solo 401(k) contribution as a tax write-off for my W-2 earned income?
I read this, but can't decipher the answer within there: https://www.irs.gov/Retirement-Plans/One-Participant-401(k)-Plans
Thank you for your help.
From your question it seems like you own the business and you W-2 yourself. Therefore any pre-tax employee contributions you might have already made (ie. employee deferrals) have already been deducted from your W-2. In a simple W-2, Box 1 (Gross income, what you pay income tax on before any adjustments) will equal Box 5 minus 401k deferrals.
Your options for shrinking your tax burden using your Solo 401k plan are a little restricted because you W-2 yourself. You've missed the opportunity for employee contributions in 2015 besides what you may have already done, so you can't shrink your personal tax burden for 2015. You could still make employer contributions for 2015 and lower your corporate tax burden. However, this is only available if you have not yet filed your business's tax return for 2015.
