What Is Planned Maintenance? A Practical Guide
- Trefnus
- Jul 26
- 13 min read
Published: 26 July 2026 | Last reviewed: 26 July 2026
Every business depends on equipment that will eventually fail. The only real question is whether it fails on your terms or on its own. Planned maintenance is the discipline of deciding in advance what work each asset needs, how often it needs it and who will carry it out, then doing that work to a schedule rather than waiting for a breakdown to force the issue.
For smaller UK businesses the appeal is practical rather than theoretical. Scheduled work can be booked when the site is quiet, parts can be ordered before they become urgent, and spending becomes predictable instead of arriving as a series of unpleasant surprises. It also produces the records that inspectors, insurers and clients increasingly expect to see.
This guide explains what planned maintenance is, the types you are likely to use, how it compares with reactive repairs, and how to build a schedule a small team can realistically sustain.
What is planned maintenance?
Planned maintenance is any maintenance activity that is defined, scheduled and resourced before the work takes place. The task is written down, the frequency is set, the parts and tools are known, and a named person or contractor is responsible for completing it.
The word "planned" describes how the work is organised, not the reason it is being done. That distinction matters, because planned maintenance covers rather more than routine servicing:
Routine servicing carried out at set intervals
Statutory inspections and tests required by law, an insurer or a client contract
Condition checks that look for early signs of wear or deterioration
Known repairs that are deliberately scheduled for a convenient date rather than dealt with in a rush
That last point often surprises people. A dripping tap you noticed on Monday and booked into Friday's maintenance round is planned corrective maintenance. It became planned the moment it was scheduled instead of being handled as an emergency.
Planned maintenance vs reactive maintenance
The clearest way to understand planned maintenance is to compare it with the alternative, which most businesses default to without ever deciding to.
Reactive maintenance
Reactive maintenance, sometimes called run to failure, means fixing things once they stop working. It has genuine advantages: nothing is spent until something breaks, and no planning time is consumed. For low value, non-critical, easily replaced items such as a desk fan or a cheap kettle, running to failure is a perfectly rational choice.
The problems appear when reactive becomes the default for equipment that matters. Emergency callouts cost more than booked visits, parts may not be in stock, failures rarely occur at convenient moments, and a component that fails suddenly can damage other parts around it.
Planned maintenance
Planned maintenance shifts the timing decision to you. Work happens at intervals you have chosen, using resources you have arranged, at a moment that suits the business. The trade off is that you will sometimes service something that had not yet failed, which can feel like wasted effort until you compare it with the cost of a failure at the worst possible time.
In practice almost every business runs a mix of both. The aim of a sensible maintenance strategy is not to eliminate reactive work, which is impossible, but to make sure the assets that would genuinely hurt you if they failed are covered by a plan.
Planned and reactive maintenance compared
Factor | Planned maintenance | Reactive maintenance |
Timing | Scheduled at a time that suits the business | Dictated by the failure |
Downtime | Shorter and anticipated | Longer and unplanned |
Cost profile | Predictable and budgeted | Emergency callout and premium part prices |
Parts | Ordered in advance | Sourced under pressure, often at short notice |
Asset life | Generally extended | Wear allowed to run to failure |
Compliance evidence | Generated as a by-product of the schedule | Difficult to reconstruct after the event |
Best suited to | Critical, costly or regulated assets | Low value items that are quick to replace |
How the terminology fits together
Maintenance vocabulary is used loosely and inconsistently, which causes a lot of confusion when comparing suppliers or software. The following table sets out how the common terms relate to one another.
Term | What it means | Typical example |
Planned maintenance | Any work scheduled and resourced in advance | A monthly service round booked into the diary |
Preventive maintenance | Work done specifically to stop a failure occurring | Replacing filters before they clog |
Planned preventive maintenance (PPM) | The overlap of the two: preventive work on a fixed schedule | An annual boiler service |
Predictive maintenance | Work triggered by monitored condition data | A vibration reading that flags a failing bearing |
Reactive maintenance | Work triggered by a failure that has already happened | Replacing a pump after it seizes |
Planned preventive maintenance, usually shortened to PPM, is the term most UK facilities and maintenance contracts use. If a contractor quotes for a PPM schedule, they mean a fixed programme of preventive visits across the year.
The main types of planned maintenance
Most maintenance programmes draw on five approaches. Few businesses need all five, but knowing the options helps you match the method to the asset.
Time-based maintenance
Work is triggered by the calendar: weekly, monthly, quarterly or annually. This is the simplest approach to plan and the easiest to explain to a team, which is why it dominates in smaller organisations. It suits equipment that deteriorates with age or exposure regardless of how much it is used, such as building fabric, drainage or emergency lighting.
Usage-based maintenance
Work is triggered by a counter rather than a date: running hours, cycles, mileage or output volume. A generator serviced every 250 running hours will be maintained appropriately whether that takes three months or eighteen. Usage-based intervals are usually more accurate than calendar intervals for machinery, but they require someone to record the readings reliably.
Condition-based maintenance
Work is triggered by an observed condition: a reading outside its normal range, visible wear, a temperature rise or an unusual noise. Condition-based maintenance avoids replacing components that still have life in them, but it depends on either regular inspection or monitoring equipment, and on someone acting on what is found.
Statutory and compliance maintenance
Some maintenance is driven by legal duties or by conditions attached to insurance and client contracts. These tasks belong in the same schedule as everything else, but they carry consequences beyond inconvenience if they are missed.
It is worth being precise about what the law actually requires. Regulation 5 of the Provision and Use of Work Equipment Regulations 1998 (PUWER) requires work equipment to be maintained in an efficient state, in efficient working order and in good repair. It describes the condition to be achieved rather than prescribing how often you must do anything.
A smaller number of duties do set intervals. Under the Lifting Operations and Lifting Equipment Regulations 1998 (LOLER), lifting equipment used to lift people and lifting accessories generally require thorough examination at least every six months. Other lifting equipment generally requires examination at least every twelve months, or in accordance with an examination scheme drawn up by a competent person.
Other duties set no interval at all. There is no legally fixed frequency for portable appliance testing, for instance. The Electricity at Work Regulations 1989 require electrical systems to be maintained so as to prevent danger, and the frequency of any testing should follow from a risk assessment rather than a rule of thumb.
The practical implication is that much published guidance on maintenance frequencies is best practice or manufacturer recommendation rather than a legal minimum. Both are worth following, but you should know which is which before defending your schedule to an inspector or an insurer.
Planned corrective maintenance
This covers known faults that are not urgent enough to justify stopping work, so they are logged and scheduled. Grouping several of these into one visit is one of the quickest wins available to a small maintenance team, because the travel time and setup are shared across multiple jobs.
Why planned maintenance matters for UK small businesses
Large organisations adopt planned maintenance for efficiency at scale. For a business with a handful of sites and one or two people responsible for keeping everything running, the benefits are more immediate.
Less disruptive downtime. Downtime happens on your terms. Servicing a compressor on a Tuesday morning costs a fraction of what it costs when it fails mid production.
Longer asset life. Equipment that is cleaned, lubricated and adjusted on schedule generally lasts longer, which pushes capital replacement further into the future.
Predictable costs. A planned schedule turns maintenance into a forecastable line in the budget rather than an unpredictable series of emergency invoices.
Safety and evidence. Well maintained equipment is safer equipment, and a documented schedule demonstrates that maintenance is being managed rather than left to chance.
Easier compliance checks. Insurers, landlords, auditors and larger clients increasingly ask for maintenance records. Producing them on request is far easier than reconstructing them afterwards.
Less key person risk. When maintenance lives in one person's head, the business is exposed the moment they are ill, on holiday or leave. A written schedule survives staff changes.
What the evidence suggests
Robust published data on maintenance costs in UK small businesses is scarce, so most of the available evidence comes from large facilities estates. The most frequently cited source is the Operations and Maintenance Best Practices Guide produced by Pacific Northwest National Laboratory for the US Department of Energy's Federal Energy Management Programme.
That guide estimates that a predictive maintenance programme can deliver cost savings of roughly 12 to 18 per cent compared with a predominantly reactive programme, and around 8 to 12 per cent compared with preventive maintenance alone. It also notes that sites heavily reliant on reactive work may find larger savings available.
Two caveats are worth keeping in mind. These figures describe large US federal facilities rather than UK small businesses, and predictive maintenance requires monitoring equipment that most smaller organisations will not have. The useful takeaway is directional rather than numerical: across a wide body of estate management practice, moving work from reactive to scheduled maintenance is consistently associated with lower total cost, not merely displaced cost.
How to build a planned maintenance schedule
Maintenance planning fails most often through over-ambition. A schedule that covers everything at generous frequencies will be abandoned within a quarter. The aim is a plan that covers what matters and that your team can actually complete.
1. Build an asset register
You cannot maintain what you have not listed. Record every asset that would cause a problem if it stopped working, along with its location, make and model, serial number, installation date and any warranty or service contract details. A spreadsheet is a reasonable starting point, though it becomes awkward once you are tracking history as well as a list.
2. Decide what is genuinely critical
Rank each asset by what happens if it fails. A useful test is to ask three questions: does a failure stop revenue, does it create a safety risk, and how long would a replacement take to source? Anything that scores badly on more than one belongs in the plan. Low value items that are quick to replace can stay reactive without guilt.
3. Set realistic frequencies
Start from the manufacturer's recommendation, then adjust for how hard the equipment works and the environment it sits in. A machine running two shifts in a dusty workshop needs attention more often than an identical machine used occasionally in a clean unit. Where a statutory interval applies, that interval is the floor rather than the target.
4. Write the task, not just the title
"Service the extraction unit" means different things to different people. A useful task states what to check, what tools and parts are needed, what a pass looks like and roughly how long it should take. Written properly, the job can be handed to someone new without a briefing, which is precisely the point.
5. Assign owners and protect the time
Every scheduled job needs a named owner, whether that is a member of staff or a contractor. Then the time has to be protected. Maintenance that is expected to happen in gaps between other work is maintenance that will not happen at all in a busy month.
6. Record completion and review the plan
Sign off each job with the date, the person who did it, what was found and any parts used. Then review the schedule at least once a year. Assets that repeatedly fail between visits need shorter intervals or replacement. Assets that never show any wear may be over maintained, and that time can be redeployed.
What to record against every planned maintenance job
Records are the part most often neglected, and the part that carries the most weight when something goes wrong.
As a minimum, capture:
The asset the work relates to and where it is located
The date the work was due and the date it was actually completed
Who carried out the work, including contractor details and any competency or accreditation relevant to the task
What was checked, what was found and what condition the asset was left in
Parts replaced, readings taken and photographs where the condition is easier to show than describe
Any follow up work identified, with a target date so it does not disappear
Common planned maintenance mistakes
Planning everything at once
Ambitious first schedules typically cover every asset on site at generous frequencies, then collapse when the workload becomes obvious. Start with your critical assets and statutory duties, prove the process works for a quarter, then extend.
Confusing activity with outcome
Completing 100 per cent of scheduled tasks means nothing if the tasks are the wrong ones. If an asset keeps failing despite being fully serviced, the task content or the interval needs to change.
Leaving the schedule in one place and the records in another
Plans in a wall planner, notes in a notebook and certificates in an email inbox produce a schedule nobody can audit. Keeping the plan and the history against the same asset record is what makes the data useful later.
Ignoring the backlog
A small number of overdue jobs is normal. A growing backlog is a warning that frequencies are unrealistic or that resources are insufficient, and it is far better addressed early than discovered during an inspection.
How to tell whether planned maintenance is working
A handful of simple measures will tell you more than a complex dashboard:
Schedule compliance. The percentage of scheduled jobs completed on time, often called PPM compliance
Planned to reactive ratio. The proportion of maintenance hours spent on planned rather than reactive work. Many maintenance teams work towards roughly 80 per cent planned as a rule of thumb, though the right figure depends heavily on your equipment and sector.
Repeat failures. The same asset failing again shortly after a visit usually means the wrong task or the wrong interval.
Downtime. Hours lost to equipment being out of service, split between planned and unplanned.
Cost per asset. Total maintenance spend per asset over time, which highlights equipment approaching the point where replacement is cheaper than repair.
Track a small number consistently rather than many occasionally. Trends matter more than absolute numbers, particularly in the first year.
Managing planned maintenance with Trefnus CMMS Once you are managing more than a few dozen assets, spreadsheets become difficult to keep accurate. Recurring schedules, completion records, photographs, contractor certificates and compliance evidence tend to end up spread across separate files, and nobody is certain which version is current. Trefnus CMMS is a computerised maintenance management system built for small and medium UK businesses. It holds your asset register, preventive and compliance activities, recurring schedules based on either the calendar or machine hours, and completion records with photographs and notes against each asset. Contracts, defects and service visits sit alongside the schedule, and the dashboard flags overdue activities and upcoming renewals. It is an offline-first app, so it keeps working on site without a connection, and it is a one-time purchase covering up to five devices rather than a monthly subscription. Find out more at: |
Frequently asked questions
What is the difference between planned maintenance and preventive maintenance?
Planned maintenance describes how work is organised, meaning it is scheduled and resourced in advance. Preventive maintenance describes why work is done, meaning it is carried out to stop a failure happening. Most preventive maintenance is planned, which is why the term planned preventive maintenance, or PPM, is so widely used in the UK. The two are not identical, though. A known but non-urgent repair that you schedule for next week is planned maintenance but not preventive, because the fault has already occurred.
How often should planned maintenance be carried out?
There is no single correct frequency. Begin with the manufacturer's recommended interval, then adjust for how intensively the equipment is used, the environment it operates in and the consequences of failure. Equipment running continuously or in dusty, wet or corrosive conditions needs attention more often than the manual suggests. Where a statutory or insurance requirement sets an interval, treat that as the minimum rather than the target, and review all intervals annually against actual failure history.
Is planned maintenance a legal requirement in the UK?
There is no single law requiring planned maintenance as such, but several duties are extremely difficult to meet without it. PUWER requires work equipment to be maintained in an efficient state and in good repair, and the Regulatory Reform (Fire Safety) Order 2005 requires fire safety equipment to be maintained in efficient working order. Specific regimes such as LOLER and gas safety legislation do set inspection intervals. In practice a documented planned schedule is the most straightforward way to demonstrate that these duties are being met.
What is a good ratio of planned to reactive maintenance?
A commonly cited industry rule of thumb is that around 80 per cent of maintenance hours should be planned and around 20 per cent reactive. Treat it as a direction of travel rather than a target to be hit, because the appropriate balance depends on the age of your equipment, the sector you work in and how much of your asset base is genuinely critical. A business moving from 20 per cent planned to 50 per cent planned over a year is making real progress regardless of the benchmark.
Do small businesses need software to manage planned maintenance?
A spreadsheet can work for a small number of assets and a single person managing them. It starts to struggle once you are tracking recurring schedules, completion history, photographs, contractor certificates and compliance evidence across multiple assets, because version control and reminders both become manual. A CMMS keeps the schedule and the history against the same asset record, generates the next occurrence automatically and produces evidence on request, which matters most when someone asks to see it at short notice.
Can planned maintenance reduce insurance costs?
Most UK insurers do not offer an explicit premium discount for having a planned maintenance programme. What good maintenance records do affect is the assessment behind the premium and, more importantly, the strength of your position at claim stage. Commercial policies commonly include conditions requiring equipment to be maintained in accordance with statutory requirements or manufacturer recommendations, and an insurer may query a claim where those conditions appear not to have been met.
Dated completion records, inspection certificates and defect histories are the evidence that demonstrates compliance with those conditions. Check the specific wording of your own policy, as requirements vary significantly between insurers and sectors.
Conclusion
Planned maintenance is not a complicated concept. It simply means deciding in advance what work each asset needs, when it needs it and who will do it, then recording what actually happened. The difficulty lies in sustaining it once the initial enthusiasm passes.
For small and medium businesses, the practical route is to start narrow. List your assets, identify the ones that would genuinely hurt you if they failed, set honest frequencies, write tasks clearly enough that anyone could follow them, and record every completion. Extend the plan once that core is running reliably.
Done consistently, planned maintenance reduces disruption, extends asset life, makes costs predictable and produces the evidence that inspectors, insurers and clients ask for. If you are currently managing all of this across spreadsheets, notebooks and email, it is worth looking at how a maintenance management system could bring the schedule and the records into one place.
Further Reading and Official Guidance
The following sources provide authoritative UK guidance on maintenance duties and good practice:
Disclaimer
The information in this article is intended for general guidance only and does not constitute professional legal, financial, or regulatory advice. Always consult a qualified professional for advice specific to your circumstances.
