Actually, it varies. I.R.C.
§ 3121(v)(1)(B) provides that a
414(h)(2) pickup is subject to FICA only "where the pickup referred to in such section is pursuant to a salary reduction agreement (whether evidenced by a written agreement or otherwise)." Thus, in what I think of as the old-fashioned pickup situation, in which an employer simply decides as an extra benefit to pick up employee contributions without deducting the pickups from wages, the pickups would not be subject to FICA. However, if the pickups reduce the employees' wages, they are subject to FICA.
Obviously, the fact that pickups must be mandatory (Rev. Ruls. 81-35 and 81-36) makes it hard to determine in some instances whether there is a salary reduction "agreement." I've always thought that there might be some room for maneuvering here. (In a collective bargaining situation, for example, is there any real difference between saying that employees' salaries, as increased for COLAs and the like, shall be reduced by X% to cover the pickup, versus saying that employees' salaries shall be increased by a lesser amount, and that the employer will pay for the pickups without a salary reduction?) However, there are a number of limitations on the room for maneuver.
One is that if you treat pickups as not being pursuant to a salary reduction agreement for purposes of section 3121(v), and therefore has not being subject to FICA, they are also not part of wages for purposes of Social Security benefits. This can be a concern for some employees and unions.
Another is that a state statute will typically treat pickups, other than those made pursuant to a salary reduction agreement, as not included in wages for purposes of benefit calculations. Similarly, other plans (
e.g., life insurance plans) may treat non-salary reduction pickups as not part of wages in calculating benefits.
Finally, public employers often have trouble competing for employees with the private sector, in those job positions in which wages are higher in the private sector. In theory, one should be able to argue that the $95x salary, plus the employer pickup of $5x, that one is offering is equivalent to another employer's offer of $100 in salary with a $5x salary reduction for the pickup. In the real world, though, the employee may see a $100x salary as better than a $95x salary, without going through the details enough to realize the equivalence.
Thus, as a practical matter, the modern trend has been to have more and more pickups involve salary reductions. But those who are dealing with the older type of pickup arrangement should be aware that FICA would not apply to it.
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