Planned maintenance: what it means, and why it isn't the same as preventive maintenance

Planned maintenance is maintenance work that's prepared before anyone starts it: the task, parts, tools, procedure, safety isolation and expected hours are worked out in advance. Preventive tasks are usually planned, but so is a corrective repair kitted and booked into the next shutdown. "Planned" describes how a job was prepared, not what triggered it.

Ask five maintenance people what planned maintenance means and you'll get at least three answers. Some say it's preventive maintenance. Some say it's anything on the calendar. Some count every repair as unplanned, even ones found weeks early and fixed in a quiet Saturday shift.

The confusion comes from one word doing three jobs. This guide separates them, then covers what a job plan contains, six plant examples, the planning workflow, and how to measure it honestly.

What planned maintenance means

A planned job is one where the thinking happened before the work. Before the technician picks up a spanner, someone has already answered:

• What exactly is the job, and what does "done" look like?
• Which parts does it need, and are they on the shelf?
• Which tools, which trade, how many people?
• How is the machine made safe, and does the job need a permit?
• How long will it take, and when can production give up the machine?

If those answers exist before the job starts, the job is planned. If the technician has to work them out at the machine, while the line waits, it isn't.

The definition says nothing about why the job exists. A calendar PM, a repair found on a round, a vibration follow-up and a shutdown overhaul can all be planned.

Trigger, preparation, timing: the three questions behind every maintenance job

Most of the confusion around planned maintenance clears up once you notice that every maintenance job has three separate properties:

1. Trigger: why does the job exist? A time or usage interval (preventive), a condition reading (condition-based or predictive), a defect someone found (corrective), or a failure (breakdown). Our types of maintenance guide covers these in detail.
2. Preparation: was it planned? Were the scope, parts, tools, isolation and hours sorted out before work started?
3. Timing: is it scheduled? Does it have a date, a time slot and a named technician or crew?

These are independent. Here's preparation and timing as a grid, with one plant example per cell:

The top-right cell is healthy as long as jobs don't sit there for months: it's the ready backlog a scheduler draws from. The bottom-left cell is the one that fools people. The job is on the schedule, so it looks under control, until the technician finds the fan needs a bearing nobody ordered. Being on the calendar didn't make it planned.

One more case: a breakdown is unplanned as an event, but the response can still be planned. If a job plan for "main hydraulic pump fails on Press 3" already exists, with the spare in stores, the repair is planned even though the failure wasn't. Example 6 below shows one.

Planned vs preventive maintenance

These two get used as synonyms more than any other pair, and they shouldn't be. Preventive is a trigger. Planned is a state of preparation.

Most PM tasks are planned, because a recurring task is easy to prepare once and reuse. But a PM work order that just says "service compressor 2", with no checklist, parts list or hours, is preventive and unplanned. The technician does whatever they remember from last time.

And plenty of planned work isn't preventive. A bearing found running hot on a route, then replaced at the next stop with the bearing, puller and procedure ready, is planned corrective work.

In the UK and in facilities management you'll also see PPM, planned preventive maintenance. That usually means the PM program itself: the recurring tasks and their intervals. If that's what you're building, see our guide to building a preventive maintenance schedule.

Planned vs scheduled maintenance

Planning and scheduling are two different jobs, and plants that run well usually treat them that way.

• Planning decides what and how. The scope, the steps, the parts, the tools, the trade, the isolation and the estimated hours.
• Scheduling decides when and who. Which day, which shift, which technician or crew, fitted around production windows and the people available that week.

Planning comes first. A planned job goes into a backlog of ready work, and the scheduler builds next week's schedule from it. Larger plants split the two roles; smaller ones give both to one person. Our maintenance planner guide covers the role.

Scheduling has its own measure: schedule compliance, the share of the week's scheduled work that got done as scheduled. Good plans with poor schedule compliance need a different fix from the reverse.

The two meanings of "scheduled maintenance"

You'll see "scheduled maintenance" used in two different ways in maintenance writing:

1. Preventive work done on a fixed timetable. A task carried out at a set calendar interval or after a set number of hours, cycles or units of use. In this sense, scheduled maintenance is a kind of preventive maintenance, and some glossaries treat "planned maintenance" as another name for the same thing.
2. Any job with a date and an assignee. This is the CMMS sense. A breakdown repair booked for tomorrow's first shift is "scheduled" here, whatever triggered it.

Agree which one your team means before you report on it. Outside industrial maintenance the phrase drifts further: car makers use it for service intervals, websites for planned downtime.

What goes into a maintenance job plan

The job plan is the concrete output of planning: the difference between a technician who starts in five minutes and one who spends the first hour finding things. A complete one covers:

• Scope and steps. What the job is, the steps in order, and what "done" looks like, including any readings to record or a test run before handing back. For recurring work this is the checklist; see our preventive maintenance checklist guide.
• Parts and their availability. Part numbers and quantities, and a check that they're actually in stores before the job is scheduled. A plan that lists a bearing that isn't on the shelf isn't ready.
• Special tools. Pullers, torque wrenches, alignment kits, lifting gear, anything not in the technician's normal kit.
• Skills and crew size. Which trade (mechanical, electrical, instrumentation), how many people, and whether a contractor or the OEM is needed.
• Isolation and permits. Which energy sources to isolate, where the isolation points are, and any lockout/tagout steps. Whether the job needs a permit to work, for example for hot work or confined-space entry.
• Estimated hours. Labor hours and elapsed time. The scheduler needs both: four people for two hours is not the same slot as one person for eight.
• Downtime and access window. Whether the machine has to be stopped, for how long, and whether the job needs a weekend, a changeover or a full shutdown.
• Reference documents. The OEM manual section, drawings, wiring diagrams, last time's job record and any known problems from previous jobs on that asset.

You don't need all eight on every job. A filter change needs a line or two; a gearbox overhaul needs every item. Match the depth of the plan to the size and risk of the job.

Planned maintenance examples from the plant floor

Six illustrative jobs, each tagged with its trigger and whether it's planned and scheduled.

1. A weekly lubrication route

Trigger: time interval (preventive) · Planned: yes · Scheduled: yes

A technician greases a packing line every Monday. The route lists each grease point, the grease type and the number of strokes. It was planned once and reused every week. This is the kind of planned maintenance most people picture.

2. A follow-up from a vibration reading

Trigger: condition reading (predictive) · Planned: yes · Scheduled: once a stop is agreed

The monthly vibration route shows a rising trend on an extraction fan's drive-end bearing. Nothing has failed. The planner orders the bearing, writes the steps and the alignment check, and books it into the next changeover. The trigger was a reading, not a calendar, but the work is fully planned. See predictive maintenance for where these findings come from.

3. A seal swap that keeps getting pushed

Trigger: defect found on a round (corrective) · Planned: yes · Scheduled: no, deferred

An operator spots a pump seal weeping. The planner kits the job: seal kit, gaskets, procedure, isolation points, two hours. Then the next two stops get cancelled for production. The job is ready but has no slot. That's deferred maintenance, and it needs an owner and a new date before the weep becomes a spray.

4. A gearbox overhaul in the annual shutdown

Trigger: time and condition · Planned: yes, months ahead · Scheduled: yes, into the shutdown

A mixer gearbox is due for its overhaul. Planning starts months earlier: bearings and seals ordered from the OEM, a crane booked, the contractor confirmed, the rebuild steps written. Shutdown work is where planning pays most, because the window is fixed and every missing part costs shutdown time.

5. A panel lamp that runs to failure

Trigger: failure, by choice · Planned: the response is · Scheduled: no task exists

Nobody inspects the indicator lamps on a control panel. When one fails, an electrician swaps it from a box of spares. There's no task, and that's deliberate: the failure is cheap and harmless. The planning happened once, when someone chose run-to-failure and stocked the spares.

6. A press pump failure with a plan already written

Trigger: breakdown · Planned: yes, in advance · Scheduled: no

The main hydraulic pump on a large press has no backup. The plant keeps a spare pump in stores and a written plan for swapping it: isolation and pressure release, lifting points, hoses and fittings, a crew of three, about six hours. The failure is unplanned. The repair isn't.

The planning workflow (and the "4 phases" question)

People often ask for "the 4 phases of planned maintenance". There isn't a standard set of four. Search for it and you'll find at least three different answers:

• inspection, cleaning, adjustment and repair (mostly HVAC service pages)
• identify, plan, schedule and execute
• a list of maintenance types: corrective, preventive, risk-based and predictive

The second is closest to how planning works, but it stops one step too early. The version that works in a plant has five:

1. Identify. The work enters the system: a PM coming due, an inspection finding, a condition reading, an operator's request, a breakdown.
2. Plan. The planner builds or reuses the job plan: scope, steps, parts, tools, skills, isolation, hours and access window. Parts get checked or ordered. The job goes into the ready backlog.
3. Schedule. The scheduler fits ready jobs into next week's capacity and production windows, and assigns people.
4. Execute. The technician does the job using the plan, and records what they actually found, used and spent.
5. Close and review. The job is closed with its real hours, parts and findings. Where the plan was wrong, such as a missing part, a step that didn't work, or hours that were way off, the plan gets corrected.

Step 5 is the one most plants skip, which is why the same job plan can stay wrong for years.

How to measure planned maintenance

The standard measure is planned maintenance percentage (PMP): the share of maintenance labor hours spent on planned work.

Planned maintenance percentage = Planned maintenance hours ÷ Total maintenance hours × 100

Two rules make it honest:

• Count planned corrective work as planned. If a repair was scoped, kitted and booked before it started, it belongs in the planned bucket, whatever triggered it. Counting it as reactive makes the number look worse than the work really is.
• Track the pair, plus what broke the schedule. Planned and unplanned hours should add up to the total. Separately, track the work that broke into the week's schedule after it was set. That's what actually disrupts the plan, and it's a different number from "unplanned".

Illustrative example. In one week a maintenance team logs 300 hours: 180 on PM routes, 45 on corrective jobs that were found early and kitted before they started, and 75 on breakdowns.

• Counting only PM as planned: 180 ÷ 300 × 100 = 60%
• Counting planned corrective as planned: (180 + 45) ÷ 300 × 100 = 75%

Same week, same work. The second number is the honest one.

Published targets vary by source, and the right number depends on your asset mix. Your own trend, measured the same way every month, is more useful than anyone's benchmark.

PMP pairs well with PM compliance, which tells you whether the preventive work that was due actually got done.

What planned maintenance won't fix

Planning makes jobs faster, safer and more predictable. It doesn't make them the right jobs. Three things it won't fix:

A well-planned job can still be pointless. A beautifully kitted PM that replaces a part on a fixed interval does nothing if that part fails at random. Planning tells you how to do the job. Deciding which jobs to do at all is a separate question, and it's what reliability-centered maintenance is for.

A high planned percentage can hide a growing backlog. Jobs that keep getting pushed stay "planned" while the risk builds. PMP measures the hours worked, not the work that wasn't done. Watch the age of the ready backlog alongside it, and give anything pushed past its date an owner, as deferred maintenance.

Planning everything isn't the goal. Some jobs cost more to plan than to just do: tightening a guard, swapping a fuse, clearing a jammed sensor. Spend planning effort on big jobs, shutdown work, critical assets and anything needing isolation or special parts, and let small jobs go straight to the floor.

Planned maintenance in TPM

In total productive maintenance (TPM), "planned maintenance" is also the name of one of the pillars. It's the pillar owned by the maintenance department, covering the PM program built on failure history and OEM intervals, alongside the autonomous maintenance pillar, where operators do the daily cleaning, checks and lubrication. Same words, narrower meaning: in TPM it names the maintenance team's share of the program, not the general idea of preparing a job before it starts.

Where a CMMS helps

A CMMS doesn't write a good job plan. The planner still decides the scope, the steps and what the job needs. What the CMMS can do is make sure a plan, once written, turns up on every job without someone remembering to print it.

In MachDatum, recurring work runs as PM plans with recurrence schedules. On the due date, auto-dispatch creates the work order and assigns it, with the checklist pre-attached and the asset linked, so the technician opens a job that already has its steps on it. Checklists are versioned and carry step instructions and photos, which covers the procedure part of the job plan, and every closed job records which version was followed. Manuals and drawings sit as attachments on the asset record, next to its full history.

Planned and breakdown work can run as separate work order types, each with its own workflow, so the planned and unplanned split is already in your work order data instead of being sorted out by hand at month end. Overdue PMs surface in the PM list, and due-date reminders go out before work slips.

We're onboarding our first group of manufacturing teams now. If your job plans live in a folder nobody opens and your PMs live in a spreadsheet, see how MachDatum CMMS handles PM plans, checklists and work orders.