According to Royal Mail, the time it takes to deliver Royal Mail recorded delivery, more properly known as Signed For, varies based on class. First-class Signed For is delivered on the next working day, including Saturdays, and second-class Signed For takes two or three working days.
Royal Mail Signed For allows you to send letters and parcels anywhere in the U.K. The recipient has to provide a signature on receipt as proof of delivery, and you can check online to see if the recipient has received your parcel. The cost of this service depends on the size and weight of the package you send and whether you have chosen first-class or second-class service.