If your partnership loss is from schedule K-1 (1065) line 14 a, then it will offset your self-employment income on schedule SE line 2, see here: https://www.irs.gov/pub/irs-pdf/f1040sse.pdf
However, losses from other boxes on your schedule K-1 will not. Or, if you don't participate in the business or aren't at risk in the business, then the losses won't offset for self-employment tax.
