Parcel delivery firms will be rushed off their feet as the number of parcel and package shipments rise by between 25% and 35% during the December holiday season, the Telegraaf reported on Friday.

The seasonal sales fever begins officially with Black Friday, a commercial initiative started years ago in the US to mark the day after Thanksgiving when Christmas shopping there begins officially.

The top shipper in the Netherlands is indisputably Bol.com where turnover has grown every year by 30% to 35%. ‘We grow faster at Christmas,’ Bol.com spokeswoman Marjolein Verkerk told the paper. ‘Last year, sales rose by 50% for Sinterklaas and by 70% at Christmas. It’s difficult to say, but we are bound to set new records,’ she said.

The same goes for Post.nl which moves Bol.com goods onward. Post.nl moves 60% of the parcels in the Netherlands, handling 17% of its annual volume in December, an estimated 29 million packages in total.

On the busiest days, rival DHL expects to move 600,000 packages, 40% more than in 2016.

Both Post.nl and DHL say that 19 and 20 December are their busiest days, mostly because there is expected to be a spike in fresh food deliveries in time for Christmas.

DPD, the third player in the Dutch parcels market, expects a doubling of business and has hired in extra personnel. DPD handles packages for international retailers in the Netherlands.