Deliveries ahead of Christmas are not arriving as planned with consumers complaining of lengthy delays, damaged packages and poor communication, according to a watchdog.

Which? found only a third of consumers (35%) had received their deliveries as expected within the last month.

More than half (56%) reported a delivery not arriving when expected, including 26% who received a package early.

One in five (21%) said at least one delivery did not arrive at all and 18% reported at least one of their packages arrived late.

Consumers also complained about long delays, lack of communication, delivery instructions being ignored and packages being damaged when forced through letter boxes.

One person reported a parcel being left under their car, another had a parcel left with a neighbour without permission – who opened it and showed it to others in the village – and a third found a fragile delivery after it had been “tossed over the gate”.

About 10% of those polled said a delivery had been left outside the door without consent, while 4% said their parcel was left in the rubbish or recycling and 3% reported a package being thrown over a hedge or fence. One in eight consumers (12%) had a delivery left with an unauthorised person, though they were still able to collect it from them. However, 2% were unable to retrieve a parcel that had been left with an unauthorised person. Of those who expected a delivery in the past month that did not arrive when planned, more than half (57%) did not complain.

In a separate survey, Which? found continuing confusion about the party responsible for botched deliveries, with only 51% of shoppers knowing that they should contact the retailer and 36% incorrectly thinking they should contact the delivery company.

Alex Neill, Which? managing director of home products and services, said: “A delivery nightmare can cause unwanted stress at this time of year, when more than ever customers want to know things will arrive in one piece and on time. Make sure you know your rights this Christmas just in case something unexpected happens.”

Which? surveyed 2,099 UK residents on deliveries between 11-12 December and 2,089 about their understanding of their rights between 6 and 7 November.