The process of complying with the Gramm-Rudman-Hollings balanced-budget act, formally known as the Balanced Budget and Emergency Deficit Control Act of 1985, begins today. Unless the courts rule that the legislation is unconstitutional, Gramm-Rudman-Hollings will take effect in the last seven months of fiscal 1986.

First, the Congressional Budget Office and the president' Office of management and Budget jointly make a revised projection, or "snapshot," of the deficit for the 1986 fiscal year, which ends Sept. 30. They report their findings to the General Accounting Office. If the deficit exceeds the $171.9 billion target for fiscal 1986, as is expected, an automatic cutback, or "sequestration" of up to $11.7 billion, split evenly between domestic and defense spending, will take effect March 1.

Meanwhile, the budget process for the next fiscal year will begin with submission to Congress of President Reagan's budget for fiscal 1987, scheduled for Feb. 3. It is expected to include more than $50 billion in spending cuts to achieve the Gramm-Rudman-Hollings deficit target of $144 billion for that year.

Congress then faces a series of deadlines, imposed by Gramm-Rudman-Hollings, for approval of its usual batch of fiscal measures for the year, including a budget resolution, appropriations bills and "reconciliation" legislation to bring spending in line with budget targets.

If Congress fails to meet the targets, the sequestration process begins again on Aug. 15, starting with a new CBO-OMB deficit projection and ending with a sequestration order Oct. 15 unless Congress acts in the meantime to bring the fiscal 1987 deficit within $10 billion of the $144 billion target.$90Helen Dewar