A commercial version of the U.S. Statutes at Large is published by West. This set is especially useful in compiling federal legislative histories as it provides citations to bill numbers, committee reports, references to dates of consideration and passage of bills, and reprints of selected committee reports. The official U.S.C. is published in full every six years with annual supplements issued in the interim. It does not have annotations and is usually two to three years out of date. Annual pocket parts update the bound volumes.
Supplementary pamphlets indicate recent revisions by code section.
The unofficial codes are more current and easier to use. The U.S.C.A. and U.S.C.S. offer different editorial enhancements so it is not a bad idea to check both. It's also a good idea to check back to the U.S. Statutes at Large volumes for the actual language of the law as initially enacted. The U.S.C. is supplemented annually by bound volumes until a new edition is produced every six years. The supplements are often several years behind schedule.