The DVLA quote around 6 weeks to complete a cherished number transfer once all documents have been received by them, although from experience we usually take no more than 7-10 working days depending on whether the registration is held on a retention certificate or on a car.
In fact we offer a super fast transfer service on most registrations for just £19.95 plus VAT where, in some cases, we are able to complete all the paperwork the same day whether you have bought the registration from us or not. Call us on 01639 888833 and ask us about super fast transfers.
Some times of the year are busier than others as you can imagine. The 3 weeks before Christmas are usually so busy that the completed documents are not delivered until the new year, and of course new car sales during March and September delay transfers by about an extra week or so.
Another delaying factor is when the donor vehicle is registered before 1960, as all vehicles registered before this time are subject to an inspection which is carried out by a DVLA approved inspector. Transfers involving inspections almost always take 6 weeks or more.