Ryanair is shutting down its website for three days in February which, it is estimated, could cost the airline £20 million.

The no-frills carrier is shutting down for 74 hours from 22:00 on February 22 to 23:59 on February 25 while it changes to a new reservations system.

While flights will continue as normal over the three days, no bookings will be taken via the website or over the phone.

Ryanair takes almost one million bookings a week, but the airline is shutting down its system on Saturday, Sunday and Monday, the busiest bookings days. Assuming the airline loses 500,000 bookings, and with passengers paying an average £47 a head, it means Ryanair could lose more than £23.5m.

The shutdown also means that customers with Ryanair bookings will be unable to make changes to their flight booking, including date changes and passenger name changes over the 74-hour period.

The airline carries on average one million passengers a week, so a shutdown that includes a Sunday and a Monday, the two most popular days of the week for booking holidays online, according to internet monitoring agency, Hitwise, means the airline could lose up to half its average weekly bookings.

The shutdown comes at a bad time for Ryanair, which announced earlier this week that the worsening economic environment in Europe combined with high oil prices could result in a 50 per cent fall in profits next year.

In the three months to the end of December, Ryanair reported a fall in income from €48million to €35million, despite a 21 per cent increase in passenger numbers and a 16 per cent rise in revenue.

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