Channel 4 is planning a significant overhaul of three unscripted commissioning departments as part of the biggest jobs cull in its 43-year history.

The British network announced on Wednesday that it would cut 340 jobs — around 28% of its workforce — before the end of the year, with details emerging about where the axe will fall.

Channel 4 is planning to merge three of its biggest unscripted units: Documentaries and factual entertainment; reality and entertainment; and specialist factual.

These teams are responsible for shows including The Great British Bake Off, Married at First Sight, 24 Hours in Police Custody, and The Piano.

The changes, first reported by Broadcast, will mean commissioning roles are roughly cut in half. One source estimated that 16 jobs will become seven. Some people are being offered voluntary redundancy.

Channel 4 declined to comment beyond Wednesday’s statement about the layoffs. Channel 4 CEO Priya Dogra said the cuts were aimed at reducing management layers, removing duplication and simplifying decision-making.

A person familiar with the changes said they were communicated internally in a “ruthless” way, with staff being told that if they received an email at a certain time, it would inform them that their job was at risk.

Insiders are describing the jobs cull as a “watershed” moment for Channel 4, as it grapples with unprecedented competition for viewers and pressure on advertising revenue.

Dogra said: “These decisions have not been taken lightly, but I strongly believe they are necessary to create a simpler, more focused and more sustainable Channel 4 that can invest a greater proportion of revenues into distinctive content, back British creativity and deliver impact for audiences long into the future.”

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