South Western Railway has revealed that at least five mobile phones have been lost on its network every day since last year.
In total, more than 1,750 phones have been logged by its lost property team since last September.
In the same period, over 600 earphones and airpods have also been logged.
The company estimates that the value of phones lost on its network in the past year may well exceed £1 million.
Phones are one of the most frequently lost items on the SWR network, along with clothing, bags, wallets and glasses.
Jerome Pacatte, Head of Stations and Revenue Protection for South Western Railway, said: “Losing a phone or any other personal belonging during a journey can cause stress and anxiety, but our lost property team works incredibly hard to reunite customers with the hundreds of items lost on our network every week.
“While it might feel impossible to get your lost property back, we successfully return many items to their owners, so we strongly encourage customers who have lost something to get in touch with us.
“To end every journey on a positive note, we advise customers to take some time before reaching their destination to double-check they have everything.”
Out of the over 1,750 phones handed into lost property since last year, just fewer than 1,000 have been successfully returned to their owners, leaving a sizeable minority unclaimed.
Customers who lose their phones or any other personal belongings during their journeys should register them via the SWR website.
If the item is handed in, customers will be able to collect it in person for free or pay to have it posted to them.
If customers think they have lost something, noting the time of the train and the carriage number will help the lost property team locate their item.
Lost property from across the network is retained at the SWR lost property office in London Waterloo station for three months, after which it can be donated to charity, sold, recycled or otherwise disposed of.