Only the most serious court cases will be heard during lockdown as the number of coronavirus cases rises.
Up to 75% of criminal trials will be suspended from Tuesday, the court service said.
The most serious cases include those where the accused is being held in custody, or the alleged offence is sexual or includes children.
Scottish Courts and Tribunals said the move would “significantly reduce the number of people required to attend court in person”.
It added: “The position across the country as a whole has changed over the last week, requiring us to review our position.
“On Friday we discussed the rapid spread of the new Covid-19 variant with senior public health officials in the Scottish Government.
“With their advice and the recognition that we have taken all the right steps in making our buildings safe, we have determined that we should focus on the most essential business to reduce travel, overall footfall and physical interaction in our courts and therefore support the public health response at this critical time.”
All criminal appeals, the Bail Appeal Court, Office of the Public Guardian and Tribunals will continue to operate virtually and remotely, as they have been doing throughout the pandemic.
The Scottish Conservatives said trial delays would “come as a body blow” to victims and witnesses.
Shadow justice secretary Liam Kerr said: “No-one disputes that public safety is paramount and these latest delays are due to the new strain of the virus, but that will do little to soften the blow for those affected and left in limbo.
“The SNP government has neglected our criminal justice system for 13 years. We already know there were thousands of delayed court cases before the first pandemic restrictions were introduced last March.
“The SNP have had ten months to deal with this and they must now work with lawyers, prosecutors, court staff and the judiciary to alleviate the impact of these postponements and find practical and safe ways to ease the logjam.
“It is also vital these postponed cases cannot be quietly abandoned. Doing so would be a betrayal of victims and risk undermining public faith in the justice system.”
Justice Secretary Humza Yousaf said: “I am acutely aware of the impact that trial delays have upon victims, witnesses and the accused, as well as on professionals working in the justice system.
“Nonetheless, it is clear that all parts of society must step up our efforts to help safeguard health, protect the NHS and save lives.
“While the very concerning rates of infection, hospitalisation and deaths present us with arguably at least as challenging a position as we faced last March, today the justice system and in particular Scotland’s courts are logistically and operationally in a much better position than in the spring when a full shutdown of criminal trials was needed.”