(Or: “Short Answer: No. Slightly Longer Answer: Still No — But Let’s Explain Why”)
Every so often, a question comes up that sounds simple on the surface:
“Can we just change their pay?”
Usually followed by:
“It’s only a small change.”
“Business is tight.”
“They’ll understand.”
And payroll, very calmly, replies:
“Not without agreement.”
Because changing someone’s pay is not just a payroll adjustment. It is a contractual change. And that brings employment law into the conversation whether we like it or not.
Let’s talk about what the rules actually say.
First: Pay Is a Contractual Right
According to Acas guidance, an employee’s pay is part of their terms and conditions of employment.
That means:
- It cannot be changed unilaterally (by the employer alone)
- It requires agreement from the employee
- It should be confirmed in writing
This applies whether you are:
- Reducing pay
- Increasing pay
- Changing pay frequency
- Moving from salary to hourly
- Altering commission or bonus structures
Even if the change seems small, it is still a change to the contract.
And contracts are not one-sided documents.
What Happens If You Change Pay Without Agreement?
This is where things become risky.
Acas is very clear — if an employer imposes a change without agreement, the employee may:
- Raise a grievance
- Work under protest
- Refuse to accept the change
- Resign and claim constructive dismissal
From a payroll perspective, it can also create issues such as:
- Unlawful deduction of wages claims
- Disputes over underpayment
- Retrospective corrections
- Reputational damage
Because if you pay someone less than they are contractually entitled to, that is not just “a payroll adjustment.”
It is potentially an unlawful deduction.
HMRC’s Position: Payroll Must Reflect Entitlement
HMRC’s role is not to decide employment disputes, but its rules are clear on one thing:
Payroll must reflect actual earnings and contractual entitlement.
If an employee is contractually entitled to £2,000 per month and you decide to pay £1,800 without agreement, payroll is reporting what was paid — but that does not make it correct.
It simply means the underpayment now exists in both payroll records and employment law terms.
And if corrected later, it may involve:
- Back pay
- Revised RTI submissions
- Adjustments to tax and National Insurance
So while HMRC does not enforce contracts, payroll still needs to operate on accurate and agreed figures.
Are There Any Situations Where Pay Can Be Changed?
Yes — but they all involve process.
1. With Employee Agreement
This is the simplest and safest route.
- Discuss the change
- Explain the reason
- Get agreement
- Confirm in writing
No drama. No disputes. Payroll processes the updated figure.
2. Flexibility Clauses in Contracts
Some contracts include clauses allowing certain changes.
However:
- They must be reasonable
- They cannot be used unfairly
- They are often tested if challenged
A flexibility clause is not a free pass.
3. Collective Agreement
In larger organisations, changes may be agreed through unions or employee representatives.
Again — agreement is still key.
4. Dismiss and Re-engage (Last Resort)
This is sometimes referred to as “fire and rehire.”
Acas guidance makes clear this should only be used:
- As a last resort
- After consultation
- With proper process
It carries significant legal and reputational risk.
What About Reducing Pay Due to Business Pressure?
This is where things often get uncomfortable.
Businesses may need to reduce costs. That is a reality.
But reducing pay without agreement is not the solution.
The correct approach is:
- Open conversation
- Clear explanation
- Exploring alternatives
- Documenting agreement
Handled properly, many employees will understand.
Handled poorly, it leads to disputes very quickly.
The Payroll Reality
Payroll cannot fix a contractual problem.
If HR or management change pay without agreement, payroll is left:
- Processing disputed figures
- Handling employee queries
- Potentially correcting errors later
- Dealing with HMRC reporting adjustments
This is why payroll should always be part of the conversation before changes are made.
Not after.
The Love Payroll View
At Love Payroll Limited, this is one of the clearest lines we draw.
We do not just process numbers.
We ask:
- Has this been agreed?
- Is this contractual?
- Is this compliant?
Because paying someone incorrectly — even with good intentions — creates far more work than doing it properly in the first place.
Final Thought
You cannot change someone’s pay just because it feels necessary.
You can change it:
- With agreement
- With proper process
- With clear communication
Anything else is not a payroll shortcut.
It is a compliance risk waiting to happen.
And in payroll, those always come back around.
