A Royal Mail franking license allows you to legally use your franking machine. You apply for it when you buy or rent your machine from an authorised Royal Mail supplier (link), not from the Royal Mail itself.
If buying a used a machine you have to make sure that you get a service contract that includes a license otherwise you’ll be using your machine illegally.
Your license will include: your business name and address and the unique serial and die number of your machine.
When you get a license you also agree to certain terms and conditions such as not tampering with your machine, agreeing to have your machine inspected once a year and agreeing that your franks appear legibly on letters/parcels you send.
The reason that a license is required is because franking machines offer substantial discounts on postage costs compared to stamps. While it would be nice to think no one would abuse or defraud the system, the truth is some people try to.
The license system keeps everyone honest and allows the Royal Mail to continue to offer substantially lower rates on franked mail.
To learn more about what you can and can’t do with your franking machine please read: The Royal Mail Scheme for franking letters and parcels 2008.Click Here To Get A Franking Machines With A License!