Federal workers hoping for a 4 percent raise somewhere along the way may not get the final word for months.

But the 300,000 white-collar feds here (for whom such a raise would mean an extra $28 million a year) and their 990,000 counterparts around the country should have a hint July 22. That is when the congressional committees that have a say on government pay raises are due to recommend a date.

During the first round of budget negotiations, the Democratic-controlled House took the advice of its Post Office-Civil Service Committee. (It is one of the few places in Congress these days where civil servant is not a four-letter word.) The committee suggested, and the House agreed, that civil servants should get their pay raise on time, according to law. That would mean Oct. 1.

The Senate, the majority of whose members are Republicans, said it thought President Reagan--who wants to forget the 1983 raise altogether--was being a little harsh. It voted a budget that called for a raise next April.

When Senate-House budget conferees got together to work out a budget both sides could live with, each gave up three months. They agreed to a 4 percent pay raise that would be effective in January. That is three months later than the House originally wanted, three months sooner than the Senate liked and nine months before the president's proposed date for the next pay raise.

The compromise budget that Congress okayed last week called for a Jan. 1 pay raise.

Now that the overall compromise budget, of which the federal pay raise is just a small part, has been approved, it goes back to the Senate and to the House. Committees with jurisdiction over various parts of the budget will come up with new recommendations or the same old ones, or okay the compromise.

The Senate Governmental Affairs Committee will probably stick with the Jan. 1 date, although it may be under pressure from one of its members, Sen. Ted Stevens (R-Alaska), to make the increase effective earlier. Although he is a key part of this administration as the Senate's assistant majority leader, Stevens is a staunch supporter of feds, partially because he represents so many of them. He is also up for reelection next year.

The House Post Office-Civil Service Committee may push for the original October 1983 pay raise date, primarily out of conviction and, maybe just a teeny bit, to put the Reagan administration on the spot with its work force.

After the dust is settled, however, Congress-watchers predict that the revised budget will call for a January 1984 pay raise date. But given the ups and downs of the budget process, and the president's opposition to the pay raise, the best advice is: Don't spend the money yet!