SMP Net Take-Home Arithmetic by Salary Band, 2026-27

What we calculate

For each gross-salary band we compute: (a) Average Weekly Earnings (AWE) = salary ÷ 52, (b) first 6 weeks of SMP at 90% AWE, (c) remaining 33 weeks at the lower of £187.18 or 90% AWE, (d) PAYE and Class 1 NI deductions on the average weekly SMP using 2026-27 thresholds (personal allowance £12,570/yr ÷ 52, NI primary threshold £242/wk, basic-rate 20% income tax, 8% Class 1 NIC), (e) net take-home for the full 39-week paid leave period, and (f) the replacement ratio (SMP avg weekly ÷ pre-leave AWE).

What this shows

The replacement ratio drops sharply for higher earners. At £25,000 gross salary, SMP replaces about 47% of pre-leave AWE — a moderate but manageable cut. At £45,000 it drops to about 32%. At £75,000+ the replacement ratio falls below 30%: the flat £187.18 rate dominates the calculation because the first 6 weeks at 90% are nearly the entire variable income. Above the basic-rate band, SMP is paid below the personal allowance per-week threshold, so tax and NI deductions are minimal — but the gross cut is large.

Implications for household planning

Two implications. First, higher-earner birth parents typically lose more income during maternity than lower-earner birth parents (in absolute terms). Second, this asymmetry is partly what makes Shared Parental Leave a poor financial deal for many higher-earning couples: ShPP is flat-rate from week 1 (no 90% AWE step), so a higher-earning birth parent who transfers leave to a lower-earning partner usually transfers low-pay weeks at the same flat rate the family already had.

How we calculated this

Average Weekly Earnings (AWE) is approximated as gross annual salary divided by 52 weeks. The formal HMRC AWE calculation uses the 8 weeks ending the qualifying week (the 15th week before the Expected Week of Childbirth) for weekly-paid employees, or 2 months for monthly-paid employees. For stable salaried roles the difference between our approximation and the formal HMRC calculation is negligible — typically less than one percent — but for variable-pay or commission-heavy roles the approximation can mislead by more substantial margins. We recommend that anyone whose earnings vary materially during the qualifying period use their actual qualifying-window payslips rather than this approximation.

The calculation ignores employer-enhanced maternity pay, which would add to net take-home, often substantially. A typical enhanced policy of 13 weeks at full pay then dropping to statutory adds tens of thousands of pounds to total net take-home for a higher earner. The calculation also ignores salary sacrifice arrangements, which can reduce the AWE used for SMP purposes if the sacrifice falls within the qualifying period. And it ignores Universal Credit overlap — UC claimants will see UC payments reduced as SMP arrives, with the 63% taper applying to SMP-derived income in the same way as wages.

PAYE thresholds use the 2026-27 personal allowance and basic-rate band. Scottish taxpayers operate under separate income-tax bands set by Holyrood and need separate calculation. High earners above £100,000 face additional complexity because the personal allowance tapers by £1 for every £2 of adjusted net income above £100,000, eliminating entirely at £125,140 — though for this group, SMP itself is usually a small fraction of normal salary and the effective marginal rate during leave is dominated by the headline cut, not the tax interaction.

National Insurance is calculated on a per-pay-period basis at 8% above the Primary Threshold (£242/week 2026-27). Because SMP payments fall above the threshold for higher earners but below it for lower earners, the NI bite varies considerably across our salary bands. Below the £242/week threshold no Class 1 NI is due — though Class 1A and Class 1B contributions on benefits in kind are still possible. For a worker whose normal monthly NI deduction is several hundred pounds, the SMP-rate NI deduction drops to single digits or zero.

The replacement ratio we calculate is the average weekly SMP divided by pre-leave AWE. This is the most intuitive number for a household planning the maternity year — it answers "what percentage of my normal weekly pay will I receive during leave?" The decline from approximately fifty-five percent at the lowest salary band to approximately fifteen percent at the highest reflects the regressive structure of UK statutory maternity pay: a flat-rate scheme inherently provides less replacement for higher earners because the flat rate is fixed regardless of pre-leave income.

The deeper implication for policy-makers is that statutory maternity replacement in the UK is genuinely inadequate for higher earners — a parent on £75,000 earning replacement of around twenty-six percent of pre-leave income for 39 weeks needs either substantial employer enhancement, household savings, or partner income to maintain household cash flow. This is consistent with the OECD's longstanding observation that the UK maternity-pay system relies heavily on supplemental employer provision to deliver adequate replacement for middle and higher earners.

For the analysis above, we limited examples to six salary bands spanning the most-common earner ranges. The arithmetic generalises straightforwardly to any other gross salary — readers wanting their specific number should use the interactive calculator with their own inputs.

Cross-checking against employer enhancement scenarios

The numbers above describe a worker receiving statutory SMP only. In practice many UK employees receive enhanced contractual maternity packages that supplement statutory pay during some or all of the 39-week paid window. The most common enhancement structures are: full pay for the first 6 weeks (matching the 90% AWE statutory step but paid as 100%); full pay for the first 13 weeks; full pay for the first 26 weeks; full pay for 26 weeks followed by half pay for 13 weeks. Each pattern adds substantial net take-home above the statutory floor.

A worker on £45,000 gross salary with a "26 weeks at 100% pay" enhanced policy receives roughly £22,500 during the first 26 weeks (full salary, taxed and NI-deducted as normal). The remaining 13 weeks of paid leave drop to the statutory £187.18/week flat rate, adding around £2,400 gross. Total gross receipts: roughly £24,900 over 39 paid weeks, versus the statutory-only figure of around £10,500 on the same salary. The enhancement nearly triples the gross paid-window income.

The CIPD's regular HR-practice surveys put the proportion of large UK employers offering an enhanced maternity package above the statutory floor at between fifty and sixty-five percent. Smaller employers offer enhancement less frequently, with the proportion dropping below thirty percent in firms with fewer than fifty employees. The presence and shape of enhancement therefore depends materially on workplace size and sector — financial services and large blue-chip employers being the most generous, hospitality and small-business sectors the least.

The longer-term financial picture

Calculating just the 39-week paid window understates the total income impact of maternity leave because most workers extend beyond 39 weeks into the unpaid weeks 40-52. A worker who takes the full 52-week entitlement receives 13 weeks of zero pay on top of the reduced 39-paid-weeks income. Total annual income impact across the full leave year can therefore be two to four times the headline replacement-ratio drop suggested by the per-week calculations.

Households planning for the maternity year typically need to combine the calculator output with: estimated employer enhancement, partner income during the leave window, accrued annual leave taken at full salary either before leave or interleaved with leave, and any savings or borrowing planned to cover the unpaid 13 weeks. The single most underused planning tool is accrued annual leave: holiday accrues at full rate during the entire 52-week maternity leave, so most workers return with five to six weeks of accrued leave ready to take at full salary, which can be staged to extend the effective paid window or to manage the return-to-work transition.

For full editorial methodology see our methodology page. Statutory rates verified against the HMRC Employers: maternity pay and leave reference page and the UK Income Tax rates and bands table for 2026-27.

Reviewed byPlainMaternity Editorial, Editorial Team