UK National Insurance Calculator

Annual NI
Monthly
Effective rate

2026/27 thresholds — Class 1 employee: 8% between PT (£12,570) and UEL (£50,270), 2% above. Employer (secondary): 15% above ST (£5,012). Class 4 self-employed: 6% LPL–UPL, 2% above.

About this tool

UK National Insurance Calculator is a single-purpose utility on instant.tw, a free toolbox of calculators, converters, generators, and quick lookups. Everything works in your browser — nothing is uploaded, nothing is stored on a server unless explicitly noted.

Category: Tax & Government — UK. Browse more Tax & Government — UK tools.