Although Washington is to the bureaucracy what Hollywood is to the movie business, the best paid federal workers in the nation live in Juneau, Fairbanks and Anchorage, not Georgetown or McLean.

Thanks to tax-free living cost differentials, a government secretary can get $75 more each week than a federal worker at the same job in Texas, California, or Massachusetts. The Grade 18 at the top of the civil service totem pole in Fairbanks gets $12,500 (tax-free) more per year than a similar VIP here.

Federal salaries for most jobs are standard nationwide. If you are a Grade 7 in San Antonio you get the same pay as a GS 7 here. But Uncle Sam does make exceptions for Alaska, Hawaii, Puerto Rico, the Virgin Islands and Guam. Using Washington as the base city -- with a 100 rating -- federal officials each year set differentials for those far-away places.

While a few people in Washington are aware of the wage differentials, annual upgradings (or downgradings) have a big impact on government types in Alaska or the islands. Alaska has about 14,000 federal workers and Hawaii nearly 24,000.

Later this month the government will raise the U.S. tax-free differential for Juneau (from 22.5 percent to 25 percent) and lower it (from 20 percent to 17.5 percent) for feds in Anchorage. Federal cost-of-living differentials will remain at 25 percent for Fairbanks. U.S. workers in Guam get a 7.5 percent (tax free) pay differential; those in Puerto Rico recently were raised from 5 percent to 7.5 percent and employes on Oahu, which has most of Hawaii's federal work force, recently went from 12.5 percent to 15 percent.

The pay differentials are more than an interesting tidbit for federal workers in other cities and states. Congress may revive a leftover Carter administration pay "reform" plan. It would gear U.S. white collar salaries to geographic areas. The Carter plan does not call for tax-free cost-of-living differentials. It would tie U.S. salaries to home-town industry levels and to the usually lower salaries of state and local government workers.

Under the Carter proposal, which the Reagan team is studying, federal workers in Detroit and New York probably would get higher pay than feds in Washington, while U.S. aides in San Antonio would get the equivalent of about 87 cents for every salary dollar paid to a counterpart in Washington. Even though Boston is considered a high-cost town, studies have shown wages there are lower than in some comparable big cities so U.S. employes there could wind up withlower salaries than people doing the same government job in Denver, Seattle or Cleveland.

Federal unions claim the pay "reforms" proposed by the Carter administration would mean future pay raises would be reduced about $1,500 for the typical worker over the next few years. Members of Congress last year showed they were leery of any pay reform plan that could reduce pay raises for government types in their areas. But that was a different Congress, and a different year.