People stuck for a stamp in Denmark will soon be able to send a text message to pay the postage on a letter.
From 1 April, the Danish post office is introducing The Mobile Postage service that does away with stamps for standard sized letters.
Instead, people will send a text to the post office and get back a code they write on the envelope.
Sweden's post office said it was also considering introducing the service and is planning trials.
Danes sending a text bearing the word "PORTO" to the 1900 number will get in return a code that must be written on a letter in the place they would usually stick a stamp.
"Mobile Postage is a useful supplement for those in need of a stamp regardless of place and time," said Henrik Larsen, a spokesman for Post Danmark in a statement.
Initially only letters up to 50g in weight can bear the mobile postal code. Getting a code will cost 8 DKK (£0.92p); the standard rate for a letter, plus the usual cost of a text message. The charge for the code will be added to a mobile user's phone bill.
Codes must be used within seven days of purchase and only on letters being posted to other addresses within Denmark.
Mr Larsen said the service was not intended to replace stamps.
"We will, of course, still keep the Danish stamp tradition alive as the stamp adds qualities to a letter," he said.
Sweden is also reportedly considering using a similar system for standard letters as well as small parcels up to 2kg in weight.