NSSF contributions are easier to manage when the two tiers are separated clearly. This guide explains the bands, limits and checks every employer should make.
The National Social Security Fund contribution is one of the most frequently misapplied deductions in Kenyan payroll. Not because the math is hard, but because the two-tier structure creates two separate calculations that look similar but behave differently. Getting them mixed up changes the contribution amount and the employer cost.
How the tiers work
Tier I covers lower-band earnings and is subject to a lower earnings ceiling. Contributions are made by both the employee and the employer at the prescribed rate, but only up to the Tier I limit. Earnings above that limit do not flow into Tier I.
Tier II covers earnings above the Tier I ceiling, up to a second upper limit. The rate is the same, but the band is different. An employee earning above the Tier I ceiling will have contributions split across both tiers, and the split must be shown correctly on the payslip and the return.
Why the split matters
If the payroll system treats the entire contribution as a single line, the return will not match the fund’s expectation. The employee record may show the wrong pensionable salary, and the employer may remit the wrong total. Reconciling this after the fact is time-consuming, especially when several months have passed.
The calculation should be transparent enough for an employee to understand from their payslip. Both tiers should be visible, with the pensionable salary and the contribution amount for each shown separately.
The checks every employer should make
Before filing, compare the payroll register with the contribution schedule. Confirm the employer and employee portions separately. Retain the working papers used to produce the return, the calculation, the bands applied and the reviewer who approved it.
A monthly reconciliation control catches errors while they are still easy to fix. A quarterly or annual review often means restating returns, explaining variances to the fund, and in some cases refunding overpaid contributions.