A guide to National Insurance Scheme (NIS) calculations for bimonthly, fortnightly, and weekly employees in 2026.
The National Insurance Scheme (NIS) is a social security programme that provides benefits to workers and their families. Both employees and employers make contributions based on the employee's insurable income.
This manual explains how NIS is calculated for , , and pay frequencies in 2026. Monthly employees are unchanged and continue to use a simple per-period ceiling.
The NIS ceiling is now applied at the level. All pay periods within the same calendar month share a single $280,000 ceiling, rather than each period having its own fixed cap.
The portion of an employee's taxable income that is subject to NIS contributions. It is capped by the ceiling—income above the cap is not insurable.
Applies when employee is under 60
Applies when employee is 60 or older (pensioner)
per calendar month, regardless of pay frequency. This ceiling is shared across all pay periods that fall within the same month.
In 2025, each pay period had its own fixed ceiling, derived from an annual amount. Periods were calculated independently—prior periods in the same month did not affect the current period.
3,360,000 ÷ 26 fortnights
insurableIncome = min(taxableIncome, perPeriodCeiling)
- Cap = $129,230.77
- Taxable ($146,031) > cap → insurable = $129,230.77
- Employee NIS = 129,230.77 × 5.6% =
- Employer NIS = 129,230.77 × 8.4% =
In 2026, the $280,000 ceiling applies to the . Periods within the same calendar month share this ceiling. The system tracks how much of the ceiling has already been used by prior periods in the month.
Calculate remaining ceiling
remainingCeiling = 280,000 − priorPeriodsInsurableIncomeThisMonth
Calculate per-period cap
perPeriodCap = remainingCeiling ÷ remainingPeriodsInMonth
Determine insurable income
monthTotal = priorPeriodsTaxableIncome + currentPeriodTaxableIncome
If monthTotal ≥ 280,000:
insurableIncome = perPeriodCap
Else:
insurableIncome = min(currentPeriodTaxableIncome, perPeriodCap)
- Prior insurable = $0, prior taxable = $0, remaining periods = 2
- Per-fortnight cap = 280,000 ÷ 2 =
- Month total = 146,031 < 280,000 → insurable = min(146,031, 140,000) =
- Employee NIS = 140,000 × 5.6% =
- Employer NIS = 140,000 × 8.4% =
- Prior insurable = $140,000 (first fortnight was capped), prior taxable = $150,000
- Remaining ceiling = 280,000 − 140,000 = $140,000, remaining periods = 1
- Per-fortnight cap = $140,000
- Month total = 150,000 + 146,031 = 296,031 ≥ 280,000 → insurable = (full cap)
- Employee NIS = , Employer NIS =
Same logic as fortnightly. Per-period cap = $140,000 when calculating the first period of the month.
$160,000 in first bimonthly period
- Per-period cap = 140,000
- Insurable = min(160,000, 140,000) = $140,000
- Employee NIS = $7,840, Employer NIS = $11,760
The number of weeks in a month varies. Typical months have 4 weeks; some have 5.
- Per-week cap = 280,000 ÷ 4 =
- Per-week cap = 280,000 ÷ 5 =
$70,000 in first week of a 4-week month
- Per-week cap = $70,000
- Insurable = min(70,000, 70,000) = $70,000
- Employee NIS = 70,000 × 5.6% =
- Employer NIS = 70,000 × 8.4% =
Fortnightly $146,031 (1st fortnight)
Fortnightly $146,031 (2nd fortnight, after $150k in 1st)
Weekly $70,000 (1st week)
In these examples, 2026 yields higher NIS because the per-period cap is higher ($140,000 vs $129,230 for fortnightly; $70,000 vs $64,615 for weekly). The 2026 method also ensures total monthly insurable income never exceeds $280,000.
The $280,000 ceiling is defined per month. The 2025 per-period ceilings (e.g. 3.36M ÷ 26 or 52) did not guarantee that total monthly insurable income stayed at or below $280,000. The 2026 method enforces the monthly limit directly.
Under 2025, an employee earning $150,000 in each of two fortnights could have insurable income of 129,230 × 2 = in one month—close to but not aligned with the intended monthly cap. Under 2026, total insurable income for the month is correctly capped at $280,000.
With bonuses or overtime, 2025 could over-insure in some months. 2026 spreads the ceiling across the actual number of periods in the month, so total monthly NIS stays consistent with the law.
Monthly employees have always been capped at $280,000 per month. 2026 applies the same monthly limit to sub-monthly staff, ensuring equal treatment across pay frequencies.
- No employee contribution
- Employer contribution at 1.5% instead of 8.4%
- No contributions
- The per-period cap adjusts automatically based on the actual number of periods in that month
(280,000 − prior insurable) ÷ remaining periods
NIS 2026 uses a of $280,000 for bimonthly, fortnightly, and weekly employees. The ceiling is shared across all pay periods in the same calendar month. Each period's insurable income is capped by its share of the remaining ceiling, and contributions are calculated at 5.6% (employee) and 8.4% (employer). This approach aligns with the statutory monthly limit, prevents over-insurance, and treats all pay frequencies consistently.