Horsecross Arts, which runs Perth Theatre and Concert Hall, has begun redundancy consultations with three quarters of its 168 staff as a "painful last resort”.
It comes as both venues remain closed due to the Covid-19 pandemic.
Horsecross Arts has launched a collective consultation process on potential redundancies with about 70 part-time and 50 full-time staff in an attempt to secure the long-term future of the organisation.
Both venues are closed until at least September. Most of the 168 staff are now on furlough, but the government’s coronavirus job retention scheme is due to wind down and close completely by the end of October.
Horsecross interim chair Steven Stewart said: "This is a painful last resort and a decision we were forced to take after all other options were exhausted."
Horsecross chief executive Nick Williams said the organisation’s income stream had been "turned off overnight" by the effects of Covid-19.
Williams said: "We had been making good progress in turning our fortunes around after a challenging period when the pandemic hit the UK and we went into lockdown.
"Even at this difficult time, we have continued to try to lift people’s spirits with online activities and we appreciate all the support we have had from our customers, funders and local communities."
Williams, who took over as chief executive in September 2019, gave a strong commitment to support staff, but stopped short of guaranteeing to bring them all back when the venues can reopen.
He said: "We will do everything we can to help and support our staff family and minimise the impact on jobs. We remain hopeful that, when we do have clear guidelines on when and how we can reopen, we’ll find a way to work with some of these wonderful people again."
Perth Theatre recently underwent an extensive £16.6m refurbishment and development programme, reopening in 2017 with a new studio theatre.