NIM01002 - Class 1 Structural Overview: Date upon which liability arises
Section 3 & 6 of the Social Security Contributions and Benefits Act (SSCBA) 1992
Earnings includes any remuneration or profit derived from an employment.
Liability for Class 1 NICs arises at the time the earnings (see NIM02000 onwards) are earned. The Class 1 NICs liability is assessed and paid when the earnings are placed unconditionally, at the employee’s disposal.