F-1 OPT FICA Guide for Foreign Founders and Employees (2025-2026)

OPT work is still filtered through the F-1 tax rules first

Founders and employees on OPT often assume that once real payroll starts, the tax file becomes indistinguishable from every other employee file. The IRS does not treat it that simply. Foreign students in F-1 status are subject to special residency and FICA rules while they remain nonresident aliens and while the employment is allowed by USCIS for that status.

That means the payroll question is not only 'is there a job?' It is also 'what status is the worker in for tax purposes right now?'

The five-calendar-year residency clock changes the picture eventually

The IRS pages on foreign students and scholars make clear that F-1 students can exclude days of presence for a limited period as exempt individuals. After that, the substantial presence and payroll consequences can change. Employers and founders make mistakes when they assume the F-1 payroll treatment stays frozen forever just because the person remained in school-related status.

The payroll file should track both visa status and tax status

A useful workpaper shows the worker's F-1 status, OPT authorization, years of presence, and whether the person is still a nonresident alien for tax purposes. That single memo often prevents FICA errors better than any year-end cleanup.