National Insurance rates and categories
Category letters
Employers use an employee’s National Insurance category letter when they run payroll to work out how much they both need to contribute.
Most employees have category letter A. Employees can find their category letter on their payslip.
There are different category letters for eligible employees who work in a special tax site within a Freeport or Investment Zone.
| Category letter | Employee group |
|---|---|
| A | All employees apart from those in groups B, C, H, J, M, V and Z in this table |
| B | Married women and widows who have a certificate of election form showing they’re entitled to pay reduced National Insurance |
| C | Employees over the State Pension age |
| H | Apprentices under 25 |
| J | Employees who can defer National Insurance because they’re already paying it in another job |
| M | Employees under 21 |
| V | Employees who are working in their first job since leaving the armed forces (veterans) |
| Z | Employees under 21 who can defer National Insurance because they’re already paying it in another job |
Category letters for eligible employees who work in a special tax site within a Freeport
Employers use these category letters for eligible employees who work in a special tax site within a Freeport. Employees who work in a Freeport but not within a special tax site should have a different category letter.
| Category letter | Employee group |
|---|---|
| F | All employees who work in a special tax site within a Freeport, apart from those in groups I, L, and S in this table |
| I | Married women and widows working in a special tax site within a Freeport who have a certificate of election form showing they’re entitled to pay reduced National Insurance |
| L | Employees who work in a special tax site within a Freeport and can defer National Insurance because they’re already paying it in another job |
| S | Employees who work in a special tax site within a Freeport and are over the State Pension age |
If you’re an employer you can check if you can use one of these category letters when you claim National Insurance relief for employees working in a special tax site within a Freeport.
Category letters for eligible employees who work in a special tax site within an Investment Zone
Employers use these category letters for eligible employees who work in a special tax site within an Investment Zone. Employees who work in an Investment Zone but not within a special tax site should have a different category letter.
| Category letter | Employee group |
|---|---|
| N | All employees who work in a special tax site within an Investment Zone, apart from those in groups E, D and K in this table |
| E | Married women and widows working in a special tax site within an Investment Zone who have a certificate of election form showing they’re entitled to pay reduced National Insurance |
| D | Employees who work in a special tax site within an Investment Zone and can defer National Insurance because they’re already paying it in another job |
| K | Employees who work in a special tax site within an Investment Zone and are over State Pension age |
If you’re an employer you can check if you can use one of these category letters when you claim National Insurance relief for employees working in a special tax site within an Investment Zone.
Category letter X
Employers use category letter X for employees who do not have to pay National Insurance, for example because they’re under 16.
Mariners and deep sea fishermen
HMRC has detailed information on National Insurance for mariners and deep sea fishermen.