I did a small job for a friend and received $1,200 in payment. Do I have to add this income under self employment income? I don’t have a business, this was a 1 time job.

[pk · Accepted solution]

If this was one time only with no expectation of profit making ( i.e. making it into a business), I would claim this to be  "other income" and not be subject to SECA.  The real question would your intention -- did you expect to be paid  for the work and was the payment at going rate for such work or is it just a friend helping a friend and the friend  just gave you some money,  If you expected to be paid  and was paid what you asked for then this is self-employment whether you continued to do this in 2018 or not 

[MichaelL1]

Yes, this is income subject to self-employment.

One time job or full time job does not matter.

You can however deduct expenses incurred in earning the income.

See below for much more detail.

https://ttlc.intuit.com/replies/3302122