National Insurance number
The National Insurance number is a number used in the United Kingdom in the administration of the National Insurance or social security system. It is also used for some purposes in the UK tax system. The number is described by the United Kingdom government as a "personal account number".
Social Security Wage Base
For the Old Age, Survivors and Disability Insurance (OASDI) tax or Social Security tax in the United States, the Social Security Wage Base (SSWB) is the maximum earned gross income or upper threshold on which a wage earner's Social Security tax may be imposed. The Social Security tax is one component of the Federal Insurance Contributions Act tax (FICA) and Self-employment tax, the other component being the Medicare tax. It is also the maximum amount of covered wages that are taken into account when average earnings are calculated in order to determine a worker's Social Security benefit.