Federal agencies, inspired by rumors of a hiring freeze, are chopping through red tape and normally slow bureaucratic procedures to fill vacant jobs as quickly as possible.

Thousands of federal slots opened up in February because an unusually large number of employes retired, to cash in on a 6 percent annuity increase. It went into effect March 1.

In addition to the heavier-than-normal turnover, government offices are reacting to persistent rumors that President Carter's federal belt-tightening program, due soon, will include some sort of hiring freeze on government.

A majority of the government's top personnel directors -- the people who head agency or departmental personnel shops -- polled by this column expect a freeze very soon. Most of the directors said that units in their departments and agencies have stepped up hiring in anticipation of the freeze, and three of 19 interviewed said they had moved to fill vacancies in their own offices because of the freeze warnings.

Insiders say some sort of freeze is likely when the president announces new government economic goals. It could take the form of a total ban on hiring or more likely, could give agencies flexibility in filling some current vacancies in the future. But unless the freeze comes quickly, most of the vacancies that now exist will have been filled, making the freeze little more than a public relations stunt.