The short answer: what you owe for a sleep-in
You owe the National Minimum Wage only for the time a sleep-in worker is awake and actually working, not for the hours they are asleep. The National Minimum Wage (NMW) is the legal pay floor every UK employer must meet. For most care home night staff the relevant figure is the top band, the National Living Wage (NLW), which applies to workers aged 21 and over.
This is the direct result of the Supreme Court's 2021 decision in Royal Mencap Society v Tomlinson-Blake. The court held that a care worker doing a sleep-in, expected to sleep but available to get up if needed, is not working for the whole shift. They are only working, for minimum wage purposes, during the time they are awake and dealing with a task. That ruling is still the law today and it is the foundation every care home night rota sits on.
So a flat sleep-in allowance is allowed. The catch is that the ruling did not give owners a free pass. It moved the risk somewhere quieter: into how the night is classified, and into the maths across the whole pay period. Get either wrong and a perfectly normal-looking rota becomes an underpayment that HMRC can pursue for years. Care home owners are exactly who this affects, which is why specialist healthcare and care sector accountants treat night-cover pay as the first thing to check, not the last.
Sleep-in or waking night: the distinction that decides everything
A sleep-in and a waking night are paid completely differently, so getting the label right is the single most important decision you make about night cover. A genuine sleep-in lets the worker sleep through, with a listening ear in case they are needed. A waking night requires the worker to stay awake and available for the entire shift.
Why does it matter so much? Because a waking night is "time work" for every hour. The worker is working the whole time, awake by design, so the minimum wage applies across the full shift. Nine hours of waking cover at £12.71 is £114.39 of pay you must reach, however you label it. A genuine sleep-in, by contrast, only counts the awake-and-working portion toward the minimum wage, which is why the flat allowance survives.
Here is where care homes get caught. A resident with advanced dementia who wanders, or someone on a one-to-one observation for safety, may need a worker awake and watching all night. That is a waking night in substance, whatever the rota calls it. The Care Quality Commission (CQC), the regulator that registers and inspects every care home in England, looks at your statement of purpose and your actual staffing against resident need. If safe care requires waking cover, you cannot pay it as a sleep-in. Both CQC on the safety side and HMRC on the pay side judge what the worker genuinely does, not the word printed on the timesheet.
A practical line we use with clients: if you would be in trouble with CQC for the worker falling asleep, it is not a sleep-in. For the regulator's own expectations on staffing and safety, the Care Quality Commission sets out what registered providers must evidence.
How the minimum wage averaging rule catches care homes
The minimum wage is tested as an average across the whole pay reference period, not shift by shift, and that is where flat allowances quietly fail. The pay reference period is usually the month for salaried care staff or the period between paydays. HMRC adds up the worker's qualifying pay for that period, divides it by their qualifying hours, and checks the result against the applicable rate.
Take a real-shaped example. A care assistant aged 24 does day shifts paid at exactly £12.71 an hour from April 2026, plus four genuine sleep-ins in the month at a flat £45 each. If all four sleep-ins are undisturbed, those sleeping hours do not count as minimum wage hours, the £180 of allowances sits on top, and the average across her counted hours stays at or above £12.71. She is compliant.
Now change one thing. Pay her day shifts at £12.71 but set a flat sleep-in allowance so low that, once you fold in the awake time she actually works each night, her counted pay divided by her counted hours dips under £12.71. That is a breach for the period, and HMRC does not just want the few pounds of shortfall. They want the arrears across every affected period, going back up to six years, plus a penalty. The averaging rule is unforgiving precisely because it hides: each shift looks fine in isolation, and only the period total reveals the gap.
The fix is not complicated, but it has to be deliberate. You set the flat allowance high enough that it comfortably covers the typical awake time, you pay separately for heavy-disturbance nights, and you run an averaging check every pay run rather than once a year at the audit. HMRC's own method is set out in HMRC's guidance on calculating the minimum wage, and it is worth a payroll lead reading it once properly.
What you owe when a sleeping worker is woken
Every minute a sleep-in worker is awake for the purpose of working counts as paid working time at the minimum wage. The listening ear itself is not paid time under the Mencap ruling, but the moment the worker gets up to reposition a resident, deal with a fall, answer a call bell or handle an incident, that is work and it must be paid at no less than the applicable rate.
This is the part that trips up homes that thought the flat allowance settled everything. Picture a £45 sleep-in allowance on a night where the worker is up for three hours dealing with two separate incidents. Three hours at £12.71 is £38.13, which the £45 covers, so no top-up is due. Change it to a night where the worker is up for four and a half hours, which is not unusual on a challenging unit. That is £57.20 of qualifying pay, the £45 allowance falls short, and you owe the difference for that shift.
So the operational reality is record keeping. You need a simple, honest disturbance log that captures when night staff were awake and working. Without it you cannot prove the awake time was paid correctly, and in an HMRC review the absence of records tends to be read against the employer, not the worker. A care home that runs a clean disturbance record alongside payroll is in a far stronger position than one relying on memory and a flat figure.
One more point owners miss: handover. If your night worker is required to stay for a morning handover, or to arrive early for one in the evening, that bracket of time is ordinary working time at the full rate. It is not part of the sleep-in and it should never be folded into the flat allowance.
The accommodation offset and other quiet traps
Beyond the sleep-in question, three smaller mechanics regularly move a care home below the minimum wage without anyone noticing. They are worth a paragraph each because each one has cost a real operator real money.
The accommodation offset. Where you provide accommodation to a worker, only a capped amount can count toward the minimum wage, set at £11.10 a day from April 2026. If you house a live-in worker or a relocating manager and the value you attribute to that accommodation runs ahead of the cap, the excess effectively reduces their pay for minimum wage purposes. Many homes apply this incorrectly and discover the gap only at review.
Agency cover. When you fill nights with agency staff you are not the agency worker's employer, so their minimum wage compliance is the agency's problem, not yours. The cost is still your problem. Agency night cover often runs at double or more the equivalent in-house hourly cost, and a home leaning heavily on agency to plug a sleep-in gap can quietly wreck its margin against occupancy. The pay-compliance answer and the cost answer pull in different directions, which is exactly the sort of trade-off a specialist should be modelling for you.
Deductions and salaried hours. Uniform charges, training cost clawbacks and till or breakage deductions can all pull pay below the floor when they bite. Salaried care staff on annual hours need a salaried-hours check too, because a worker paid an even monthly salary across an uneven shift pattern can dip under the rate in a heavy month. And from April 2026, Statutory Sick Pay (SSP) becomes payable from day one of sickness rather than day four, which lifts the real cost of covering a night worker who calls in sick. None of these is exotic. They are simply the things that get missed when night pay is set once and never revisited.
The Fair Pay Agreement: what changes from 2028
The current sleep-in position is settled law, but it is not permanent, and the change coming is significant enough to plan for now. The Employment Rights Act 2024 created an Adult Social Care Negotiating Body, a sector-specific pay body for adult social care in England. It is expected to begin operating in 2026, hold its first negotiations in 2027, and produce a first Fair Pay Agreement that takes effect in 2028.
Why does this matter for a sleep-in post? Because sleep-in payments and travel time are explicitly among the terms the negotiating body is examining. A Fair Pay Agreement will be binding on adult social care employers and enforceable in the same way as the minimum wage, through a new Fair Work Agency. So it is realistic that from 2028 the sector moves from "minimum wage for awake time only" to a contractual sleep-in rate that sits above today's position, set centrally rather than home by home.
Nothing changes the rules for the 2025/26 or 2026/27 tax years, so do not over-correct. The sensible move is to build flexibility into your night-cover budget and your staff contracts now, so that when a Fair Pay Agreement lands you can absorb a higher sleep-in cost without a contractual fight. Owners who treat 2028 as a known future cost rather than a surprise will be the calm ones. This is the kind of forward modelling we walk through with care home clients alongside the day-to-day numbers, and you can see the wider picture in our guide on how much an accountant costs for a care home.
Here is how the three common approaches actually compare for getting care home night pay right:
| What you need | DIY / payroll software | Generic accountant | LOYALS specialist |
|---|---|---|---|
| Tells a genuine sleep-in from a waking night | ✗ You self-classify | ● If you ask | ✓ Checked at onboarding |
| Runs the NMW averaging test every pay run | ● Only if configured | ✗ Usually annual | ✓ Every pay run |
| Flags disturbance top-ups owed on heavy nights | ✗ | ✗ | ✓ Built into payroll |
| Reads CQC staffing need against the pay model | ✗ | ✗ | ✓ Sector knowledge |
| Models the Fair Pay Agreement cost from 2028 | ✗ | ● | ✓ Forward budgeting |
| Open Mon to Sat for an urgent payroll question | ✗ | ✗ Mon to Fri 9 to 5 | ✓ 10am to 7pm Mon to Sat |
This is why care home operators tend to move night-cover payroll to a specialist rather than leave it to generic software or a high-street firm.
What this means for you: what to do before your next payroll run
The practical work here is a short review you can do once and then keep current, and most of it is sequencing rather than anything technical.
- Label every night shift honestly. Walk your rota and mark each night as a genuine sleep-in or a waking night, based on what the worker actually has to do, not on which is cheaper. If a resident needs eyes-open cover, it is a waking night.
- Run the averaging test at the April 2026 rate. Take each night worker's qualifying pay and qualifying hours across a full pay period and confirm the average reaches at least £12.71 an hour for the over-21s. Do it now, before the rate rises, so you are not caught out in the first April payroll.
- Set a disturbance record. A simple log of when night staff were awake and working protects you in an HMRC review and tells you which nights need a top-up.
- Check the accommodation offset and any deductions. If you house staff, confirm the value attributed sits within the £11.10 daily cap, and check no uniform or training deduction pushes anyone under the floor.
- Budget for 2028. Pencil in a higher sleep-in cost from the Fair Pay Agreement so it is a planned number, not a shock.
- Keep the evidence. Rotas, contracts, disturbance logs and payroll records together are what turn an HMRC enquiry from a worry into a non-event.
None of this requires a lawyer for the everyday cases. It requires someone who knows the care sector running your payroll with the sleep-in rules in front of them, every month, rather than discovering a gap years later. Done at the right time it is quiet housekeeping. Left to chance it is the most expensive surprise a care home owner can get from HMRC.