The National Assessment Agency is spending pound;6 million on the service, provided by Parcelforce Worldwide, aimed at reducing costs and workload for schools. From January next year, schools will no longer have to pay postage on bundles of completed examination papers, but simply hand packages to a courier.
A spokeswoman for the NAA said it was "very rare" for papers to be lost in the post, but it did happen occasionally.
She added: "It is important that we do as much as we can to secure the exam system because pupils have worked so hard, revising and spending hours writing their answers."
In a trial of the new system in Leeds, no papers were lost, although the agency conceded that errors could still occur.
Exam boards will still be required to have systems in place to assess students if answer-papers go missing.
A share of pound;6.5m in funding is also being offered to exams officers in schools to upgrade equipment, and the NAA is publishing a good practice guide that explains how an exams office should be run.
The NAA spokeswoman said that under the workforce agreement, fewer exams officers were teachers, so they were not as familiar with the qualifications system.
The good practice guide for exam officers will be available from www.naa.org.uk from January, or contact TSO (The Stationery Office): tel 08700 606015