401k +i401k what is max contribution amount age <40 combined for 2018, employee maxed at 18500K between both plans?

[Anonymous]

401k through employer was getting w2 then so employee and employer contributions (from employer)

i401k income will allow max amount 54K for 1099 self employed after I quit employed job and did self employment. So did employee and employer contributions maxed out (one employer only myself), sole proprietor with an EIN
Combined they both come out to <55k but more than 54K, again employee maxed out combined both 401k plans to 18500, is that allow since part of the total <55K but >54K comes from a W2.

[dmertz]

Making elective deferrals at the W-2 employer means that less than $18,500 of elective deferrals can be made to the individual 401(k).  Since TurboTax's Maximize function for a self-employed 401(k) contribution is incapable of factoring in the elective deferrals made at the W-2 employer, if you did not max out the $18,500 at the W-2 job you can enter a self-employed elective deferral of up to $18,500 minus your elective deferral to the W-2 job.  Then, to cause TurboTax to calculate the maximum for only the permissible employer contribution, you must use the Maximize function for either a SEP contribution or a Profit Sharing Keogh instead of for a 401(k) contribution; the employer contribution calculation is the same for any of these.

[Anonymous]

I had a little bit of trouble using this, can we presume a total AGI of 200k and what would the numbers be?

[dmertz]

AGI is not used in the calculation.  The values needed to do the calculations are net profit from the self-employment reported on Schedule 1 line 12, the deductible portion of self-employment taxes shown on Schedule 1 line 27 and any amounts with code D or code AA in box 12 of your W-2.