A document published by the Internal Revenue Service that details how members of the clergy or other religious workers are to pay Social Security and Medicare taxes. These two types of taxes are collected through either the Self-Employment Contributions Act (SECA) system or the Federal Insurance Contributions Act (FICA) system, but not both. IRS Publication 517 indicates which forms of income are subject to SECA and which are subject to FICA rules.

Whether or not a religious worker is covered under SECA or FICA depends heavily on the type of religious order. For example, religious workers who work for an organization in which a vow of poverty is taken are exempt from SECA, and are thus covered by FICA. A religious worker who does not take a vow of poverty is not exempt from FICA, and is thus covered by SECA. Since SECA is for self-employed workers, different rules apply to how net earnings are treated.