On 2017, the bus in Oxford left luggage with potatoes, adult toys and mannequin heads.
The Lost and found office of Oxford Bus said it had 4,123 items left in its service this year.
Most items have never been recycled.
Passengers charged only 964.
Unclaimed lost property was donated to local charities.
The lost property includes a pair of one-eyed glasses, a ski stick, a Soviet hat, false teeth and a Halloween costume.
Jed Dixon, customer relations officer, said: "We always try to reunite passengers with their belongings and we encourage everyone to check their personal belongings before leaving the bus.
"Unfortunately, a lot of things do get left behind and we will hold them for a fixed period of time if they are claimed.
"Clothes and mobile phones are often left on the bus, but we also collect a lot of unusual items.
"The driver who finds an unclaimed item is entitled to it, but every year we find ourselves with a large number of unclaimed items.
"The company has donated all unrecovered findings to local charities, many of which are clothing and household items.
The company said that the recovery of the property requires a management fee of £ 1 to the passenger, which is equivalent to the storage cost.