Facing a projected $294 million budget shortfall, Gov. Charlie Baker’s office said today it will offer buyouts to roughly 42,000 executive branch employees, with the potential of layoffs to follow if his administration’s belt-tightening isn’t enough.

The Baker administration made the announcements amid an already gloomy financial forecast in which tax revenues have repeatedly lagged estimates.

Kristen Lepore, Baker’s budget chief, said in separate letters that tax revenues are now estimated to fall $175 million below expectations, helping to create what she said is a $294 million deficit in the state budget.

Lepore said officials are looking to cut executive budgets by 1 percent, but in the meantime, they’ll begin a so-called “separation incentive” program on Monday that will run through Nov. 14. The state will offer a $15,000 one-time cash buyout to as many as 12,000 employees who are eligible to retire, as well as a $5,000 buyout to roughly 30,000 other executive branch employees.

If all those actions aren’t enough to close the gap, administration officials warned that layoffs could follow.

“It is our strong desire to achieve savings through the voluntary separations,” Baker’s budget office said. “After the program is complete, we will assess whether we need to further reduce the workforce.”

Officials said they will not offer furloughs or a different version of the early retirement program they offered last year to cut spending.

State officials said they don’t intend to cut local aid or “core services,” citing the Department of Children and Families’s budget as an example.

They also pointed to remarks Baker made yesterday to reporters, reminding them that he had vetoed $265 million in spending from this year’s $38.9 billion budget, all but $34 million of which the legislature overrode.