Yes, half is treated the same as a W2 employee, and half is subtracted from Adjusted Gross Income, similar to an employer deducting the portion of FICA they paid for their employees.
"Compute self-employment tax on
Form 1040, Schedule SE.pdf
. When figuring your adjusted gross income on Form 1040, you can deduct one-half of the self-employment tax. You calculate this deduction on Schedule SE (attach
Form 1040, Schedule 1.pdf
,
Additional Income and Adjustments to Income
). The
Social Security Administration
uses the information from Schedule SE to compute your benefits under the social security program."
https://www.irs.gov/taxtopics/tc554
