Introduced in early 2003, the Downstream Access solution enables transport operators - other than Royal Mail - to move mail throughout the UK to Royal Mail Inward Centres where Royal Mail completes the final end delivery.

The key benefit to the posting client is lower costs, as the transportation from collection point to the Royal Mail Centres can be performed at a lower cost than Royal Mail currently offers. The main providers that have, so far, taken advantage of offering this service are: TNT Mail, UK Mail, DHL Global Mail, and now Citipost.

The full deregulation of the market took place in January 2006, allowing posting clients to take full advantage of additional services. For example, selection of alternative delivery agents from Royal Mail to increase quality of service and reduce costs, zonal pricing - delivery charge based on density of delivery locations, and pricing in proportion - which will change the existing charging mechanism of weight to include the size of the items being posted.