The parent company of the Guardian and the Observer has announced plans to furlough about 100 non-editorial staff in an effort to reduce costs amid industry-wide falls in revenue because of the coronavirus pandemic.

Although Covid-19 coverage has driven record numbers of readers to the Guardian’s website, the economic slowdown has caused a collapse in the advertising market.

Annette Thomas, the newly appointed chief executive of Guardian Media Group, told staff on Wednesday that the company had seen record increases in digital subscriptions and online contributions from readers.

The Guardian’s unique browsers doubled to hit a record 366m in March, according to internal unaudited figures, with readers clocking up 2.17bn page views.

However, revenue projections for the first six months of the financial year alone are down by at least £20m – about 10% of Guardian News and Media’s annual income.

As a result, the company has introduced a number of measures, including postponing pay rises for all UK staff and reducing pay for the management team – including Thomas and Katharine Viner, the editor-in-chief – by 20% for the next six months.

Approximately 100 people in non-editorial departments will be placed on the government’s job guarantee scheme but their salaries will be topped up by the company to their full normal rate.

Most major British publishers have already had to reduce staffing levels or adjust pay, as the industry faces up to a crisis that could put some outlets out of business.

On Wednesday the Financial Times – which has more than a million paying subscribers – revealed that 80 senior managers would be taking a 10% pay cut as the company tried to avoid wider redundancies. Staff were told parts of the company had suffered “sudden and severe revenue shocks”.

The Daily Telegraph is also asking non-editorial employees to take 20% pay cuts and work four-day weeks. Almost every major news publisher in the UK has now imposed substantial cost reductions.

A spokesperson for the Guardian said the pandemic meant that the business was facing “huge financial challenges” and would “continue to review opportunities for further savings”.

The spokesperson added: “With record digital traffic and reader engagement driving record levels of digital subscriptions and reader support over the past six weeks, the Guardian is a strong and trusted brand. While we are well-placed to weather difficulties thanks to the strategy implemented over the last four years, it is clear that we will need to adapt as we always have, in order to serve Guardian readers and meet the challenges and opportunities ahead.”