Payroll Auto-Enrolment Mistakes Costing UK SMEs

Payroll auto-enrolment can appear straightforward: assess employees, calculate deductions, submit the payroll and send the contributions to the pension provider.

In practice, one incorrect setting can affect every employee and repeat during every pay period. An employee may be assessed using the wrong earnings, pension deductions may not reach the provider, or a payroll submission may be accepted by HMRC even though the workplace pension remains incorrect.

By the time the mistake is discovered, the employer may owe months of backdated contributions, payroll corrections and professional fees. The Pensions Regulator may also take enforcement action where legal duties have not been completed.

For small employers, proper payroll compliance UK is therefore about more than producing payslips. PAYE reporting, workplace pension assessments, employee communications and pension-provider payments must all agree.

Who Must Be Automatically Enrolled?

An employer must generally automatically enrol a worker who ordinarily works in the UK, is aged between 22 and State Pension age and earns at least £10,000 a year.

For the 2026/27 tax year, the annual automatic-enrolment trigger remains £10,000. For monthly payrolls, the equivalent pay-period trigger is £833. The qualifying-earnings band remains between £6,240 and £50,270 a year, equivalent to £520 and £4,189 a month.

These figures are used for different purposes. The £10,000 threshold determines whether an eligible worker must be automatically enrolled, while the qualifying-earnings band may be used to calculate contributions.

The government’s 2026/27 automatic-enrolment threshold review confirms that the £10,000 trigger and the £6,240-to-£50,270 qualifying band have been maintained.

Employees who do not meet all the automatic-enrolment conditions may still have a right to opt into or join a workplace pension. Depending on their age and earnings, the employer may also be required to contribute.

Mistake One: Assuming Part-Time or Temporary Staff Are Exempt

A worker does not become exempt simply because they work part-time, have a temporary contract or are completing a probationary period.

Automatic enrolment depends on the legal worker relationship, age, earnings and where the work is ordinarily performed. A casual worker whose hours fluctuate may cross the earnings trigger during a busy pay period and become eligible.

This frequently affects hospitality businesses, retailers, care providers, construction companies and seasonal employers. Someone who normally earns £700 a month may receive overtime, commission or holiday pay that takes their earnings above the applicable monthly trigger.

Payroll should therefore assess the workforce during every relevant pay period. Relying solely on the employee’s expected annual salary can cause eligible workers to be missed.

Employment status also requires care. Calling someone self-employed in a contract does not necessarily prevent them from being treated as a worker for automatic-enrolment purposes. The actual working arrangement must support the classification being used.

Mistake Two: Using Postponement Incorrectly

Employers can postpone automatic enrolment for up to three months from certain permitted dates. This can be useful for temporary workers, employees on probation or businesses setting up their pension processes.

However, postponement is not an informal three-month exemption. It can only begin from specified dates, including the employer’s duties start date, the worker’s first day or the date the worker first becomes eligible.

The employer must also send the required postponement notice to each affected worker within six weeks. Employees retain certain pension rights during the postponement period, including the right to ask to join.

The Pensions Regulator’s postponement guidance confirms both the three-month limit and the communication requirement.

Simply leaving the employee out of the pension for three months without creating and recording a valid postponement can result in backdated enrolment and contributions.

Mistake Three: Applying the Wrong Earnings Thresholds

Payroll software must contain the correct automatic-enrolment thresholds for the tax year and the employee’s pay frequency.

Using an annual threshold against a weekly or monthly payroll can produce incorrect assessments. The same problem can arise when weekly employees are transferred to monthly payroll or when old thresholds remain within the software after a tax-year update.

For 2026/27, the monthly qualifying-earnings limits are £520 and £4,189, while the monthly automatic-enrolment trigger is £833. The weekly figures are £120, £967 and £192 respectively. The Pensions Regulator publishes the complete automatic-enrolment earnings thresholds.

An employer should not manually adjust somebody’s pension status merely because the automatic payroll result appears unexpected. The assessment date, pay-reference period, date of birth, earnings and pension scheme settings should first be checked.

Mistake Four: Calculating Contributions on the Wrong Pay

The statutory minimum contribution is generally 8% of the relevant earnings, of which the employer must pay at least 3%. However, not every workplace pension calculates contributions using exactly the same definition of pay.

Some schemes use qualifying earnings. Others use basic salary, total earnings or another certified basis. Scheme rules may determine whether overtime, bonuses, commission and other payments are pensionable.

A payroll operator who assumes every scheme uses the same calculation may underpay contributions for the entire workforce.

For example, an employer may configure contributions as 3% and 5% of basic salary even though its scheme certification requires particular variable payments to be included. Alternatively, it may deduct contributions from the first pound of pay when the selected scheme basis uses the statutory qualifying-earnings band.

The Pensions Regulator warns that pensionable pay can differ from qualifying earnings and that scheme rules may treat overtime and bonuses differently. Its contribution guidance should be read alongside the pension provider’s documentation.

How a Small Calculation Error Becomes a Five-Figure Problem

Suppose ten monthly paid employees each earn £2,000 and the employer uses the standard qualifying-earnings basis.

For 2026/27, monthly qualifying earnings would generally be £1,480 per employee after applying the £520 lower threshold. At the minimum total contribution rate of 8%, that represents £118.40 per employee each month.

Across ten employees, the total minimum contribution is £1,184 a month—or £14,208 over a full year. The employer’s minimum 3% portion alone would be £5,328.

This simplified example ignores individual tax-relief arrangements and scheme-specific rules, but it demonstrates how quickly an incorrect payroll setting can create thousands of pounds in missing pension savings.

Backdating the contributions does not necessarily end the cost. The business may also need to reconstruct payroll records, correct employee deductions, communicate with the pension provider and respond to The Pensions Regulator.

Mistake Five: Using the Wrong Contribution Rates

Some employers assume the minimum employer contribution is the complete pension requirement. It is not.

Where the statutory minimum basis applies, total contributions must normally reach at least 8%, with the employer paying a minimum of 3%. The remaining amount is generally provided by the worker and applicable tax relief, depending on whether the scheme operates relief at source or a net-pay arrangement.

The employer may also have promised higher contributions within employment contracts or the pension scheme rules. In that situation, paying only the statutory minimum could still breach the contractual or scheme obligation.

Payroll must clearly identify the employer rate, employee rate, tax-relief method and pensionable-pay basis. Copying settings from another employer or pension scheme is unsafe because the arrangements may be different.

Mistake Six: Mishandling Maternity and Other Family Leave

Pension calculations during maternity, paternity, adoption and shared-parental leave require particular attention.

During paid maternity leave, the employee’s own contribution is normally based on the pay they actually receive. The employer’s contribution may need to be calculated using the pay the employee would have received had they not been on maternity leave.

Reducing both sides of the contribution calculation to the statutory maternity payment can therefore underpay the employer contribution.

Similar issues can arise with adoption and shared-parental leave. The precise position depends on the scheme and the type of leave, so payroll staff should not make manual changes without checking the applicable rules.

The Pensions Regulator lists miscalculated maternity-pay contributions among the common workplace pension errors found during its investigations.

Mistake Seven: Allowing Employees to Opt Out Before Enrolment

An employee cannot usually avoid the automatic-enrolment process by telling the employer in advance that they do not want a pension.

Where the legal conditions are met, the employer must first enrol the worker. The worker can then follow the pension scheme’s formal opt-out process.

An informal email, verbal conversation or tick box on a company form is not necessarily a valid opt-out notice. In most cases, the formal notice must come through the pension scheme rather than being supplied by the employer.

The worker normally has a one-month opt-out window. If a valid notice is received within that period, the employer should arrange the appropriate refund through payroll.

Employers must never pressure workers to opt out, suggest that opting out will improve their recruitment prospects or offer an alternative benefit on condition that they leave the pension. The Pensions Regulator’s opt-out guidance confirms that the employee’s decision must be made freely.

Mistake Eight: Sending Contributions to the Pension Provider Late

Deducting pension contributions on the payslip is not enough. The money and the related contribution schedule must reach the pension scheme.

Employee contributions deducted from pay must generally be paid to the scheme by the 22nd day of the following month when paid electronically, or the 19th when paid by cheque. A scheme may require an earlier contractual date.

A direct debit failure, rejected pension file or insufficient bank balance can leave contributions unpaid even though the payroll itself was processed successfully.

This is particularly dangerous when nobody checks the pension-provider portal after uploading the file. A confirmation that the file was uploaded does not always mean that every employee record was accepted or that the payment cleared.

The business should reconcile the payslip deductions, payroll pension report, provider submission and bank payment after every pay run. The Pensions Regulator confirms the statutory payment deadlines in its workplace pension contribution guidance.

Mistake Nine: Assuming an Accepted FPS Confirms Pension Compliance

An accepted Full Payment Submission does not prove that the workplace pension has been processed correctly.

The FPS reports pay and deductions to HMRC under Real Time Information. The pension contribution schedule and payment are separately sent to the pension provider. The two processes use some of the same payroll data, but they are not the same compliance obligation.

A payroll can therefore receive a successful HMRC response while the pension file remains rejected, the contribution is calculated incorrectly or the direct debit fails.

Equally, the pension provider may receive the correct contribution while the FPS contains an incorrect pay date, tax code, National Insurance category or year-to-date figure.

Strong payroll compliance UK requires both systems to be checked independently and reconciled to the same underlying payroll records.

PAYE RTI Errors That Commonly Accompany Pension Mistakes

Employers must normally submit an FPS on or before the employee’s payday. The submission should contain the correct payment date, pay, Income Tax, National Insurance and relevant deductions.

Common PAYE RTI errors include missing an employee from the FPS, submitting the same employment twice, using an incorrect payroll ID, applying the wrong starter declaration, failing to record a leaving date and reporting the wrong National Insurance category.

Entering the processing date instead of the employee’s contractual payday can also make a submission appear late. Sending the FPS too early creates another risk because changes made before the actual payday may require a correction.

Where no employees are paid during a tax month, an Employer Payment Summary may still be required. An EPS may also be needed to claim reductions such as statutory-payment recovery.

HMRC’s current payroll reporting guidance confirms that the FPS is generally due on or before payday and that an EPS must be sent by the relevant deadline where required.

The Financial Consequences of PAYE RTI Errors

HMRC may charge monthly late-filing penalties according to the number of employees within the PAYE scheme.

The penalty is £100 for a scheme with one to nine employees, £200 for 10 to 49 employees, £300 for 50 to 249 employees and £400 for 250 or more employees. A further percentage-based penalty may apply where a failure continues for three months.

Although HMRC normally does not penalise the first late-reporting failure in the tax year, repeated late or missing reports can quickly create a pattern of non-compliance. HMRC may also estimate what the employer owes where the expected FPS or EPS has not been submitted.

The full rules and available grounds of appeal are explained in HMRC’s late payroll reporting guidance.

Incorrect RTI information can also distort the employer’s PAYE account and create unexplained liabilities. Employees may receive incorrect tax calculations, while inaccurate payment dates or earnings can affect income-related assessments made using payroll data.

Mistake Ten: Correcting the Payslip but Not the FPS

When payroll discovers an error, the correction must reach every affected system.

Changing a payslip or entering an adjustment within the next payroll does not automatically correct a previous submission to HMRC. The employer must follow the appropriate FPS correction process and ensure that year-to-date values remain accurate.

Depending on the mistake and timing, it may be possible to correct the figures in the next regular FPS or submit an additional FPS. HMRC provides specific procedures for incorrect pay, deductions, National Insurance categories and closed tax years in its payroll error guidance.

The pension provider may require a separate adjustment file. The employer should confirm whether the original contribution was underpaid, overpaid or allocated to the wrong employee.

Corrections should create a clear audit trail. Historical payroll data should not be silently overwritten in a way that removes evidence of the original submission.

Mistake Eleven: Forgetting New Starters and Leavers

New starters create several connected responsibilities. Payroll must obtain and process the P45 or starter declaration, create a unique employee record, assess pension eligibility and send the appropriate workplace-pension communication.

If the employee is postponed, the correct notice must still be issued. If they become eligible after a pay rise, birthday or variable payment, payroll must recognise the change at the correct time.

Leavers also require careful treatment. Their final payment may contain holiday pay, commission or another amount that affects pension contributions. The correct leaving date must be included in the FPS, and any payment made after the P45 requires the appropriate payroll treatment.

Removing an employee from the pension file before processing their final pensionable payment can cause a contribution shortfall.

Mistake Twelve: Missing Staff Communications and the Declaration

Automatic enrolment involves more than deductions and payments.

Employers must write to their staff explaining how automatic enrolment affects them. New employers should generally complete these communications within six weeks of their duties start date.

A declaration of compliance must then be submitted to The Pensions Regulator within five months of the duties start date. The declaration is still required where the employer concludes that nobody needs to be automatically enrolled.

The declaration does not replace the underlying duties. Submitting it with inaccurate information or before confirming that the pension scheme is operating properly can create serious problems.

The Pensions Regulator’s new-employer duties guidance explains the communication and declaration requirements.

Mistake Thirteen: Forgetting Three-Year Re-Enrolment

Approximately every three years, employers must reassess certain eligible employees who opted out or stopped pension membership and place those who meet the conditions back into an appropriate scheme.

Postponement cannot be used for cyclical re-enrolment in the same way it can for a new employee.

Employers must also submit a re-declaration of compliance. This is required even where no employees need to be put back into the scheme.

The re-declaration is normally due within five calendar months of the third anniversary of the employer’s duties start date or relevant previous re-enrolment date. The Pensions Regulator’s re-enrolment guidance explains the recurring process.

Because three years is a long interval, the duty is easily lost when payroll staff, accountants or software providers change.

Mistake Fourteen: Keeping Inadequate Records

Employers must be able to show how workers were assessed, when communications were issued, which pension scheme was used and when contributions were paid.

Most automatic-enrolment records must be retained for at least six years. Opt-out records must generally be kept for four years. PAYE records must normally be kept for three years from the end of the tax year to which they relate.

The records should include employee assessments, postponement notices, opt-in and opt-out requests, contribution calculations, provider acknowledgements, payment evidence and declarations of compliance.

A payroll report alone may not prove that the money reached the pension scheme. The provider confirmation and bank transaction should also be retained.

The Pensions Regulator sets out the pension requirements within its record-keeping guidance, while HMRC explains the separate PAYE record-retention rules.

Outsourcing Payroll Does Not Transfer the Legal Responsibility

A business can appoint an accountant, payroll bureau or pension adviser to perform the administrative work. However, the employer remains legally responsible for ensuring that its duties are completed.

The engagement should clearly identify who assesses employees, sends statutory communications, uploads pension files, authorises direct debits, submits the FPS and monitors provider rejections.

Confusion arises when the payroll provider assumes the employer will approve the pension payment while the employer believes the provider has completed everything.

Every task should have a named owner and a deadline. The employer should receive confirmation that both the HMRC submission and pension-provider process were successful.

What Penalties Can The Pensions Regulator Impose?

The regulator may first issue a warning or compliance notice requiring the employer to correct the failure. Ignoring the notice can lead to a fixed £400 penalty.

Continued failure can produce an escalating penalty of between £50 and £10,000 per day, depending on the employer’s size. The penalty can continue growing until the statutory notice is satisfied or the regulator stops it.

Separate civil penalties may apply to unpaid contributions, while prohibited recruitment conduct can produce penalties of between £1,000 and £5,000. Wilfully refusing to enrol eligible workers or knowingly supplying false information can be treated much more seriously.

The regulator’s enforcement guidance explains the available notices and penalties.

Paying a fine does not remove the original obligation. The employer may still need to enrol workers, calculate missing contributions, make payments and complete the required declaration.

What Should You Do If You Discover a Payroll or Pension Error?

Do not ignore the problem or wait for the pension provider, HMRC or an employee to raise it.

Preserve the original payroll reports, FPS receipts, pension files, provider messages and payment records. Establish which employees and pay periods are affected before changing the data.

The employer should then reconcile gross pay, pensionable pay, employee deductions, employer contributions, FPS figures and amounts received by the pension scheme.

Where an eligible employee was never enrolled, the employer may need to backdate the pension membership and contributions to the appropriate date. The Pensions Regulator states that the employer must pay the missing employer contributions, while employees may usually need to pay their own share unless the employer chooses—or is required—to cover it.

Any related FPS or EPS error should be corrected using HMRC’s approved process. The pension provider should be contacted to confirm how it wants adjustment schedules and backdated payments submitted.

If The Pensions Regulator has already issued a notice, respond by its deadline. Correcting the underlying mistake quickly does not guarantee that a penalty will be cancelled, but continued delay can make the position considerably worse.

How to Prevent Auto-Enrolment Mistakes

Reliable payroll requires a documented process rather than dependence on one person remembering every duty.

Before each payroll is finalised, new starters, leavers, birthdays, pay changes, variable earnings and statutory leave should be reviewed. Pension assessments should then be checked before payslips and submissions are approved.

After processing, the business should confirm that the FPS was accepted, the pension file passed the provider’s validation checks and the pension payment cleared for the expected amount.

Periodic reconciliation should compare payroll deductions with the pension-provider account employee by employee. The re-enrolment date, declaration deadline, software-renewal dates and tax-year updates should also be recorded in a central compliance calendar.

How SAS Yorkshire Can Help

SAS Yorkshire helps small employers manage payroll and workplace pension responsibilities as one connected compliance process.

The team can assess new starters, operate PAYE, calculate pension contributions, prepare payroll reports and submit RTI information to HMRC. Payroll records can also be reconciled with pension-provider submissions to identify rejected files, missing employees and contribution differences.

Where historic errors are discovered, SAS Yorkshire can review the affected periods, calculate the corrections and help the employer organise the information required by HMRC, the pension provider or The Pensions Regulator.

Regular payroll support can also cover employee changes, statutory payments, year-end reporting and reminders for re-enrolment and re-declaration.

Whether your business employs two people or fifty, a properly controlled payroll process can protect cash flow, employee trust and the company’s compliance record.

Stop Small Payroll Errors Becoming Large Liabilities

Most expensive payroll failures do not begin with deliberate non-compliance. They begin with an unchecked software setting, a missed email or an incorrect assumption about one employee.

The damage grows when that mistake repeats every week or month.

An auto enrolment pension should be assessed accurately, contributions should reach the provider on time and every PAYE submission should reflect the payroll actually paid.

Contact SAS Yorkshire for a payroll and workplace pension review. The team can identify compliance gaps, correct historic problems and manage your future payroll with clear controls and reliable deadlines.

This article provides general information based on the 2026/27 rules. Workplace pension and payroll treatment can depend on the worker’s circumstances, pension scheme and pay arrangement. Professional advice should be obtained before making corrections.

Frequently Asked Questions

1. What is the minimum auto-enrolment pension contribution in 2026?

Where the standard statutory minimum applies, the total contribution is normally at least 8% of qualifying earnings, with the employer paying at least 3%. The employee and applicable tax relief generally provide the balance. A scheme may use a different certified contribution basis or require higher rates, so employers should check their provider documentation and employment contracts.

2. Do part-time employees have to be automatically enrolled?

Part-time employees are not automatically exempt. A worker must generally be enrolled when they are aged between 22 and State Pension age, ordinarily work in the UK and earn at least the applicable £10,000 annual or equivalent pay-period trigger. Workers below the trigger may still have a right to opt in or join.

3. What happens if an employer forgets to enrol an employee?

The employer should investigate immediately and may need to enrol the worker retrospectively, calculate missing contributions and submit backdated amounts to the pension scheme. The Pensions Regulator may require the employer to pay both its own and the employee’s missing contributions. Enforcement notices and financial penalties may also apply if the failure is not corrected.

4. Does an accepted FPS mean the workplace pension is correct?

No. HMRC’s FPS acceptance confirms that the RTI submission passed its validation process. It does not confirm that the pension contribution was calculated correctly, that the pension-provider file was accepted or that the money reached the scheme. These stages must be checked and reconciled separately.

5. Can PAYE RTI errors be corrected after submission?

Yes. Many errors can be corrected through the next regular FPS or an additional FPS, depending on the mistake and timing. Employers should preserve the original records, use HMRC’s correct procedure and ensure that year-to-date figures remain accurate. Any related pension-provider records may require a separate adjustment.