For most companies dealing with the government, the government's shutdown yesterday pretty much meant business as usual.

Although government officials were in a great turmoil, trying to determine what programs should be terminated temporarily and what activities were so essential that they should be continued, the chaos didn't appear to have any serious impact on major business dealings.

Federal banking regulators continued to supervise the nation's banks, largely because the operations of the Federal Reserve system and the comptroller of the currency are funded by member banks, not by the government.

But even at the Federal Home Loan Bank Board,, about four-fifths of the agency's 1,500 employes were directed to keep working because they were regarded as "essential to the safeness and soundness of the industry the agency regulates."

Meanwhile, the Internal Revenue Service continued to collect taxes, and the Treasury still held its weekly Monday bill auction, offering the public $9 billion in securities.

The General Services Administration, however, halted all sales of materials from the national stockpile, including its program to auction silver. However, the agency hasn't had any acceptable bid at its last two weekly silver auctions.

At the Securities and Exchange Commission, agency officials continued to process registration statements from corporations seeking permission to sell securities--so long as the statements had been received by last Saturday, the day the agency's funds ran out. The processing was "essential to the orderly functioning of the securities market," an agency official explained. However, the agency had not yet decided whether it had the authority to process any registration forms received since Saturday.

Similarly, the Commodity Futures Trading Commission continued to maintain its surveillance of the commodity markets as well as its investigations, audits and litigation in which the commission was involved. However, the commission froze the processing of registration applications for people who deal or want to deal in commodities. But, according to an agency spokesperson, commodity dealers who were applying for renewal registrations would not have been penalized if their old one had run out.

The Occupational Safety and Health Administration kept its 1,200 inspectors on the job to continue to conduct health and safety inspections at work places. The Food and Drug Administration also directed its inspectors to continue their surveillance of food and drug plants and health-care production facilities.

Meanwhile, Justice Department lawyers were urged to conduct "essential ongoing litigation" although they were barred from bringing or investigating new cases, unless they risked default in a case or a statute of limitations was running out.

Among the trials considered "essential" was the government's 6-year-old suit to break up American Telephone & Telegraph Co.

But not all trials continued. At the Federal Trade Commission, several staff attorneys from Cleveland and Chicago were sent home after the case they were scheduled to argue here in Washington before an agency law judge was canceled. Meanwhile, a group of Michigan attorneys scheduled to make an oral argument before the commission yesterday afternoon were notified at the Detroit airport yesterday morning that the hearing had been canceled. The agency's chief antitrust official, Thomas J. Campbell, also had to cancel his scheduled appearance before a congressional hearing because it would have been a felony for him to testify.

Also at the FTC, the smoking machine, which measures tar and nicotine content in cigarettes, took a breather.

But at the Consumer Product Safety Commission, laboratory tests continued. Although almost all of the agency's 633 employes were sent home in mid-afternoon, at least one stayed on to feed its 70 rabbits and 180 rats.