Short answer
Headcount shows how many people sit in a plan, but operational capacity depends on when those people are available, what work demand arrives, how long it takes, and which skills it requires. A useful workforce planning worksheet converts demand and supply into comparable hours, checks critical skills and time windows separately, and records the assumptions behind every gap.
Use this guide after the software shortlist
This guide covers one calculation that planning software should support. It does not propose another vendor list. For scenario controls, integrations, permissions and procurement questions, use the workforce planning tools comparison. For evidence about who can perform defined work, use the enterprise talent mapping guide.
The CIPD workforce planning factsheet defines workforce planning around balancing labour supply, including skills, with demand. It also distinguishes numerical planning from the context needed to understand the numbers. That distinction matters because two teams with 20 employees can have very different capacity.
A headcount total hides four planning questions
Ask these questions before treating a filled position as available capacity:
- How much work will arrive? Record units of demand by period, location and service level.
- How many usable hours are available? Subtract known commitments such as leave, training, meetings and administration from scheduled paid hours.
- When and where are those hours available? A monthly surplus cannot cover a Friday-night shortage if the schedule cannot move.
- Which work can those hours cover? General capacity cannot absorb a specialist queue when the required capability, authorisation or equipment is missing.
Highland Council's current workforce planning guide describes activity analysis as translating forecast work into hours while considering workforce capability. It also tells planners to allow for training, planning, communication, administration and absence. The worksheet below makes those assumptions visible rather than hiding them inside an FTE ratio.
Worksheet 1: convert demand into hours
Choose one decision period. A month may suit budget planning, but a week, day or shift may be necessary for service coverage.
| Demand item | Units expected | Minutes per unit | Demand hours | Time window | Required skill or authority | Evidence and confidence |
|---|---|---|---|---|---|---|
| Example: standard request | units × minutes ÷ 60 | Source, date, range | ||||
| Example: specialist request | units × minutes ÷ 60 | Source, date, range | ||||
| Fixed work | Enter hours directly | Source, date, range |
Use a range when volume or handling time is uncertain. Keep the base, lower and upper assumptions in separate rows or scenarios. An average can conceal peaks, rework or a small queue whose service deadline matters.
Avoid counting the same work twice. If the handling-time observation already includes routine documentation, do not add that documentation again as fixed work. Record whether breaks and handovers sit inside the service time or inside the supply deduction.
Worksheet 2: calculate available service hours
Use scheduled hours for the period, not a generic annual FTE figure. Apply known local rules and agreements rather than assuming every paid hour can be reassigned.
| Supply item | Hours | Source or owner | Can timing move? | Skill or authorisation | Confidence |
|---|---|---|---|---|---|
| Scheduled paid hours | Roster or plan | ||||
| Planned leave and expected absence | Subtract | Roster and agreed assumption | Usually limited | ||
| Training and onboarding | Subtract | Learning plan | Sometimes | ||
| Meetings, administration and handovers | Subtract | Work observation or diary | Sometimes | ||
| Other reserved duties | Subtract | Named work owner | |||
| Available service hours | Scheduled hours minus deductions |
Do not use the worksheet to erase necessary recovery time, safe staffing, accessibility needs or contractual limits. The International Labour Organization's guide to balanced working-time arrangements treats schedules as decisions that should work for employees as well as the enterprise. Capacity is a planning constraint, not permission to fill every minute.
Work a fictional example from end to end
The following support operation is fictional. Its figures demonstrate the calculation and do not provide a benchmark for another organisation.
Step 1: calculate monthly demand
The team forecasts:
- 5,400 standard cases at 18 minutes each:
5,400 × 18 ÷ 60 = 1,620 hours; - 600 specialist cases at 36 minutes each:
600 × 36 ÷ 60 = 360 hours; - scheduled quality reviews and handovers:
240 hours.
Total forecast demand is 1,620 + 360 + 240 = 2,220 hours.
Step 2: calculate monthly supply
The roster contains 20 employees scheduled for 160 paid hours each, or 3,200 hours. The planning team records:
- 240 hours for planned leave and its documented absence assumption;
- 160 hours for required training;
- 320 hours for meetings, administration and other reserved duties.
Available service capacity is 3,200 - 240 - 160 - 320 = 2,480 hours.
At the monthly total, coverage is 2,480 ÷ 2,220 = 1.117, or about 112%. The apparent surplus is 260 hours. Headcount and the monthly total both suggest that the plan is covered.
Step 3: test time and skill constraints
The schedule tells a different story:
| Constraint | Demand hours | Available matching hours | Gap | Coverage |
|---|---|---|---|---|
| Late-week service window | 580 | 460 | -120 | 79% |
| Specialist-authorised work | 360 | 300 | -60 | 83% |
These gaps are views into the same monthly plan. Do not add them automatically: some specialist cases may also arrive in the late-week window. The team should locate the overlap before calculating any extra requirement.
The worked example supports a precise conclusion: the team has enough aggregate hours under the stated assumptions, but its current schedule and specialist coverage do not match demand. It does not prove that the team needs more permanent headcount.
Worksheet 3: turn the gap into options
For each verified constraint, compare more than one response.
| Gap | Option | Assumption to test | Owner | Earliest effect | Cost or trade-off | Review measure |
|---|---|---|---|---|---|---|
| Time-window gap | Adjust voluntary shift coverage | Suitable hours can move within agreements | Operations | Covered hours and employee impact | ||
| Skill coverage | Develop additional authorised staff | Training and supervised practice fit the deadline | Operations and L&D | Demonstrated coverage after training | ||
| Demand peak | Change intake or service design | Some work can move without harming service | Service owner | Demand moved and service result | ||
| Persistent capacity gap | Recruit or source temporary capacity | Gap remains after feasible redesign | HR and Finance | Available qualified hours |
A training action initially consumes capacity. A schedule change may solve timing without increasing total hours. Process redesign may reduce demand, while recruitment may arrive too late for the next peak. Keep those effects in the scenario instead of labelling every difference a vacancy.
Review assumptions against actuals
At the end of the period, compare forecast and actual values for:
- demand units and handling time;
- hours available by time window;
- planned and unplanned deductions;
- qualified coverage for constrained work;
- actions completed and the gap that remains.
Record why an assumption changed. A planner should be able to tell whether the previous gap came from demand, schedule, capability, process or weak evidence. Replacing the date on an unexplained ratio does not make the plan current.
Where conversations may add evidence
Roster, finance and operational systems should remain authoritative for hours, costs and formal records. A focused employee or manager conversation may help test why a handling-time assumption changed, what prevents a schedule from working, or which process creates rework. Treat each account as context for human review, not as verified capacity or an individual score.
Lontra can be tested on one bounded planning question through one campaign with up to 30 invitations over 60 days, with no card required. Managers receive a brief rather than raw conversations. The product does not calculate headcount, connect itself to a planning system, predict staffing needs or make workforce decisions.
Keep the calculation tied to a decision
Headcount is still useful for positions, budgets and reporting. The mistake is asking it to answer a capacity question by itself. Define the work, convert demand into hours, calculate available supply, test the schedule and required skills, then compare feasible actions with named owners. That produces a workforce plan people can challenge and update.