I sent a birthday card recently to my elderly mother,using a first class stamp.She received a note from the post office that the price of postage for that card had been underpaid and that the card would not be delivered,unless the sum of £1.06 was paid to a Post Office.My wife paid the outstanding postage amount,and was given a receipt.Underpayment-6p-charge £1.00.The card was not huge-but be warned.
