The House begins debate today on several budget plans that would give U.S. workers a 4 percent raise this fall rather than the zero increase favored by the Senate, the 5 percent originally projected by the president, or the 14 percent-plus that unions say is due. Confused? Welcome to the budget club.

The House Budget Committee has approved a budget that would give federal white-collar workers (there are 300,000 here) a 4 percent raise this October, in 1983 and in October 1984. That plan also would limit retirees (100,000 here) to a4 percent raise every year for the next three years, no matter how much the cost of living increases.

A substitute Republican budget, which differs on many items, also allows for a 4 percent U.S. pay raise and 4 percent increase next March for retirees.

Yet another substitute, offered by Reps. Les Aspin (D-Wis.) and Norman Mineta (D-Calif.) sets the same 4 percent limit on federal pay raises but would allow retirees to get full inflation catch-ups with no "cap" on amounts.

Dozens of amendments will be offered to each of those three budget plans. Of primary interest to federal workers are amendments to give them a 5 percent or 7 percent raise this year, and to let retirees get full COL raises.

Once the House decides on a budget, it will have to confer with the Senate, which is backing a plan to freeze federal pay this year and defer the March 1983 COL raise for retirees until 1984, when they would get a 4 percent increase. The next federal pay raise, under the Senate plan, would be 4 percent in October 1983.