Statutory Payslip Deductions: An Employer's Guide
Every Full Payment Submission must reach HMRC on or before payday, and late filings attract penalties starting at £100 per month [6]. At the same time, no PAYE tax deduction may exceed 50% of an employee's relevant pay for the period [4]. Between those two constraints sits the employer's core payroll duty: calculating statutory deductions correctly, in the correct order, every pay period.
Statutory deductions are the amounts an employer must withhold because legislation requires it, regardless of what the employment contract says and without needing the employee's consent. They are also the deductions HMRC and other authorities check most closely, because the employer is collecting money on behalf of the state, the Student Loans Company, pension schemes and, occasionally, courts.
This guide works through each statutory deduction family in the order payroll software processes them, the rules that govern each one in the 2026-27 tax year, and the reporting obligations that follow. It is written for employers and payroll bureaux rather than employees; readers looking for a payslip-by-payslip explanation should start with the companion article on payslip deductions.
Key takeaways
- Statutory deductions comprise PAYE income tax, employee National Insurance, student and postgraduate loan repayments, auto-enrolment pension contributions and court-ordered attachments.
- The calculation order matters: pension deductions under a net pay arrangement reduce taxable pay before PAYE is applied, and attachment orders are calculated on net earnings after everything else.
- The 50% overriding limit caps any PAYE tax deduction at half of relevant pay, on every tax code, not just K codes.
- Child maintenance orders must leave the employee with at least 60% of net earnings, the protected earnings proportion.
- Every statutory deduction must be itemised on the payslip and reported to HMRC on or before payday via the FPS.
What makes a deduction statutory
Section 8 of the Employment Rights Act 1996 requires every deduction to appear on an itemised pay statement with its amount and purpose [13]. Within that statement, deductions split into three legal families: statutory (required by legislation), contractual (authorised by a contract clause), and voluntary (agreed in writing by the worker) [14].
The statutory family is the largest on most payslips and the only one the employer operates without discretion. It covers PAYE income tax, employee Class 1 National Insurance, student and postgraduate loan deductions, minimum auto-enrolment pension contributions, and attachment orders served by courts, local authorities, the Child Maintenance Service or the DWP [1]. Get one of these wrong and the liability usually lands on the employer, not the employee.
The statutory deduction sequence
Payroll software does not calculate deductions in the order they appear on the payslip. Each step feeds the next, so sequence errors compound. The table below shows the standard processing order for a typical employee.
| Step | Deduction | Calculated on |
|---|---|---|
| 1 | Salary sacrifice (if any) | Reduces gross pay before everything else |
| 2 | Pension, net pay arrangement | Gross pay, before tax |
| 3 | PAYE income tax | Taxable pay, per the tax code |
| 4 | Employee National Insurance | Gross earnings for NI, per category letter |
| 5 | Student and postgraduate loans | NIable gross earnings above the plan threshold |
| 6 | Pension, relief at source | Net pay, after tax |
| 7 | Attachment orders | Net earnings, after steps 1 to 6 |
Two consequences follow. A net pay pension scheme changes the tax calculation but not the National Insurance calculation, which is always run on gross earnings [1]. And attachment orders always come last, because their legal definition of earnings is net of tax, National Insurance and pension contributions [12].
PAYE income tax
Income tax is deducted through the tax code HMRC issues for each employment. For 2026-27 the standard code remains 1257L, reflecting the £12,570 Personal Allowance, with bands of 20%, 40% and 45% in England and Northern Ireland, Scottish rates under S codes and Welsh rates under C codes [11].
K codes and negative allowances
A K code signals that an employee's taxable benefits or tax debts exceed their Personal Allowance, so an amount is added to taxable pay rather than deducted from it [4]. K codes are common where company cars or large benefits in kind are payrolled, and they are the historical reason the overriding limit exists [4].
The 50% overriding limit
Since 6 April 2015 the overriding limit applies to every tax code: the tax deducted in any period cannot exceed 50% of the employee's relevant pay for that period [4]. Where a cumulative code would breach the limit, the excess is not collected that period, and the code may need operating on a week 1/month 1 basis [1]. The employer is responsible for applying the limit; HMRC-recognised payroll software applies it automatically.
Employee National Insurance
Employees pay Class 1 contributions at 8% on earnings between £242 and £967 a week, and 2% above that, while the employer pays 15% above the £96 weekly Secondary Threshold [3]. Only the employee contribution appears as a payslip deduction; the employer contribution is a cost shown alongside, never netted from pay.
Category letters drive the calculation
The NI category letter on each employment record determines which rates and thresholds apply [2]. Most employees sit on letter A, but the exceptions matter because several letters remove the employer charge entirely up to a threshold.
| Letter | Who it covers | Effect |
|---|---|---|
| A | Standard employees | Standard employee and employer rates |
| M | Under 21 | No employer NI up to £50,270 |
| H | Apprentices under 25 | No employer NI up to £50,270 |
| V | Veterans, first 12 months of civilian work | No employer NI up to £50,270 |
| C | Over State Pension age | No employee contribution |
Applying the wrong letter is one of the most common payroll errors, and HMRC expects the employer to correct the record and adjust contributions when it is discovered [2]. Bureaux managing dozens of schemes typically automate category assignment through a multi-client payroll dashboard rather than relying on per-client manual checks.
Student and postgraduate loan deductions
Student loan deductions start only when HMRC instructs the employer, through a start notice (SL1 or PGL1) or a new starter declaration, and stop only on an HMRC stop notice [10]. The deduction is 9% of earnings above the plan threshold for Plans 1, 2, 4 and 5, and 6% above £21,000 for postgraduate loans, calculated per pay period and rounded down to the whole pound [10].
A worked example for Plan 2, which carries a £29,385 annual threshold in 2026-27: an employee paid £3,200 in a month has a monthly threshold of £2,448.75, an excess of £751.25, and a deduction of £67 after rounding down [10]. An employee with both an undergraduate and a postgraduate loan repays both concurrently, 9% plus 6% on the respective excesses [7]. Employers running high headcounts across multiple plans, common in enterprise payroll, depend on the start and stop notices being applied the same week they arrive.
Pension contributions under auto-enrolment
The minimum auto-enrolment contribution is 8% of qualifying earnings, with at least 3% from the employer [8]. The employee share is a statutory deduction in the practical sense: the employer must enrol eligible jobholders and deduct contributions unless and until the employee opts out.
The opt-out mechanics touch the payslip directly. An employee who opts out within one month of enrolment is entitled to a full refund of contributions, and that refund must flow back through payroll and appear on the payslip [8]. The duty then renews: roughly every three years the employer must re-enrol eligible workers who previously opted out and re-declare compliance to The Pensions Regulator [9].
Attachment orders: statutory deductions for third parties
Attachment of earnings orders, council tax attachments, child maintenance deduction from earnings orders (DEOs) and DWP Direct Earnings Attachments (DEAs) all compel the employer to deduct from net earnings and pay a third party. Two protections frame every calculation.
For child maintenance DEOs, the employee must keep at least 60% of net earnings, the protected earnings proportion; where the full deduction cannot be taken, the shortfall carries forward to the next pay period [5]. For DEAs, the banded rates take up to 20% of net earnings at the standard rate and 40% at the higher rate, again subject to the 60% floor [12]. The employer may also deduct £1 per pay period towards administrative costs for operating a DEO or DEA, provided this does not take pay below the National Minimum Wage [5].
Operationally, orders arrive mid-cycle, carry distinct reference numbers, and must be applied in priority order when several run at once. This is exactly the category of edge case where manual payroll breaks down, and where per-payslip software pricing, of the kind set out on the Moonworkers pricing page, tends to cost less than the time spent recalculating by hand.
Reporting statutory deductions to HMRC
Every statutory deduction calculated must also be reported. The FPS carries each employee's pay, income tax, National Insurance, student loan and pension contribution data to HMRC on or before payday [6]. The deductions then crystallise as an employer liability, payable to HMRC by the 22nd of the following month for electronic payments [15].
Late or missing FPS filings trigger monthly penalties from £100, rising with PAYE scheme size, plus an additional 5% charge on tax and National Insurance reported more than three months late [6]. Only HMRC-recognised software can submit RTI at all, which is why recognition is the baseline for any serious payroll product. The same submission logic is available to platforms that embed payroll through an HMRC-recognised payroll API, where each FPS is generated and filed programmatically from the host product.
Conclusion
Statutory deductions are less a list than a pipeline. Salary sacrifice and net pay pensions reshape gross pay, the tax code converts taxable pay into income tax within the 50% limit, category letters drive National Insurance, plan notices drive student loans, and whatever remains defines the net earnings that attachment orders can reach. An employer who understands the sequence can predict any payslip line; an employer who does not will struggle to explain even a correct one.
The compliance burden is structural, repeating every pay period, and it grows each time legislation adds a plan type, a relief category or a new statutory payment. The practical answer is software that encodes the sequence once and applies it identically across every employee, every scheme and every pay run.
Frequently asked questions
Which payslip deductions count as statutory deductions in the UK?
PAYE income tax, employee Class 1 National Insurance, student and postgraduate loan repayments, minimum auto-enrolment pension contributions, and court or government attachment orders such as DEOs and DEAs [1]. These require no employee consent, unlike contractual or voluntary deductions.
What is the maximum that can be deducted from a payslip by law?
PAYE tax is capped at 50% of relevant pay in any period under the overriding limit [4]. Child maintenance and DWP attachment orders must leave the employee with at least 60% of net earnings [5]. National Insurance and student loans have no cap as such, but their percentage structure makes them self-limiting.
Does an employer need an employee's permission to deduct student loan repayments?
No. The employer must start deductions when HMRC issues a start notice or the starter declaration indicates a loan, and must continue until HMRC sends a stop notice [10]. The employee cannot pause or adjust the deduction through their employer.
In what order are statutory deductions calculated?
Salary sacrifice and net pay pension contributions first, because they reduce taxable pay; then PAYE income tax; then National Insurance on gross NIable earnings; then student loans; then relief at source pension deductions; and finally attachment orders, which are computed on the resulting net earnings [12]. Payroll software enforces this sequence automatically.
