Call Centre Shrinkage: What It Is, Why It Matters & How to Calculate It
Call centre shrinkage is the percentage of paid time that agents are not available to handle customer contacts (calls, live chat, emails and so on) — due to breaks, meetings, training, leave, sickness, coaching, late starts, system downtime, and more.
It's the reality gap between the people you pay for and the people actually available to serve customers.
Get it wrong and you'll under-staff, miss service levels, burn out your team, and overspend fixing it later. Get it right and staffing, CX, and costs all improve together.
What it is
The proportion of paid agent time lost to non-queue activities and absence — breaks, leave, training, meetings, sickness, outages — expressed as a percentage.
Why it matters
Ignore it and even a perfect volume forecast fails: you roster too few people, miss service levels, and pay more to recover. It's the backbone of accurate staffing.
What this guide covers
The definition, planned vs unplanned shrinkage, why it matters, how to calculate it (with a free calculator), how to reduce it, and quick-answer FAQs.
What is Call Centre Shrinkage?
Call centre shrinkage is the proportion of agent time lost to non-queue activities or absence, expressed as a percentage of total paid time.
In practice, shrinkage explains why "we rostered 100 people" turns into "we only had 82 actually taking calls."
Rule of thumb
If you don't plan for shrinkage, your plan isn't a plan — it's a wish.
Types of Shrinkage
There are two main categories of call centre shrinkage that WFM teams monitor and manage.
Understanding the difference between planned and unplanned shrinkage is essential for accurate forecasting, targeted action plans, and realistic staffing models.
By tracking both separately, you can identify the biggest drivers of lost time and develop strategies to reduce their impact.
Planned shrinkage
Activities you can schedule and forecast:
- Paid breaks and lunches
- Team meetings and huddles
- Training and coaching
- Annual / paid leave
- Project or back-office work
Unplanned shrinkage
The surprises that punch holes in your day:
- Sick leave and personal emergencies
- Unscheduled breaks, lateness or early finishes
- IT or telephony outages
- Ad-hoc escalations, rework, or compliance locks
Why Shrinkage Matters
Understanding why call centre shrinkage matters is critical for every Workforce Management (WFM) leader, team manager, and operations director.
Shrinkage isn't just a number on a report — it's the hidden factor that determines whether your contact centre can meet demand, hit service levels, and control costs.
If you don't account for it, even the most accurate volume forecasts will fail, leaving customers waiting longer, agents under pressure, and the business paying more to recover.
🎯 Meeting service levels
Shrinkage reduces the number of people actually available to take calls, answer chats or respond to messages. Don't factor it in and you'll roster too few people — leading to longer waits, missed SLAs, and frustrated customers.
💰 Managing costs
Ignoring shrinkage forces expensive fixes like overtime, last-minute casuals, or pulling staff off other work. Building it into your plan keeps budgets stable and predictable.
🛟 Protecting your team
Under-staffing from unplanned shrinkage piles pressure on the people who did show up. That stress drives burnout, absenteeism and turnover — which makes shrinkage worse still.
How to Calculate Call Centre Shrinkage
Calculating call centre shrinkage is about working out what percentage of your total paid staff time is lost to things other than handling customer contacts. There are two ways to look at it — and they both give the same result.
Time-based
Compare the total minutes paid with the minutes actually available for customer work.
Shrinkage % = (Time Not Available ÷ Total Paid Time) × 100Headcount-based
Compare how many people you need to meet demand with how many are actually available.
Shrinkage % = ((Required Staff − Available Staff) ÷ Required Staff) × 100Worked example
Say your forecast needs 50 agents available to meet your service level.
After breaks, leave, training, and absenteeism, you only have 40 ready to take contacts. That's:
((50 − 40) ÷ 50) × 100 = 20% shrinkageWhen building rosters, flip the formula to work out how many people to schedule:
Scheduled = Required ÷ (1 − Shrinkage)With 20% shrinkage (0.20) and 40 needed, you'd schedule 40 ÷ 0.8 = 50 agents.
Free Call Centre Shrinkage Calculator
How to Reduce Shrinkage
To reduce call centre shrinkage, treat it as an operational problem you can diagnose and control — not a mystery.
Separate planned and unplanned shrinkage, measure them monthly (and by interval where possible), then target the biggest drivers with specific actions.
Feed the realised numbers back into your next roster so improvements actually stick.
Split the problem
Track planned vs unplanned shrinkage separately, and target the bigger bucket first.
Schedule smart
Avoid loading meetings and training into peak demand windows. Use micro-coaching in quiet intervals.
Tighten adherence
Clear start/finish rules, realistic break spacing, and supportive leadership — not surveillance theatre.
Improve attendance
Wellbeing programs, fair workloads, flexible rosters, and early intervention reduce sick leave.
Harden tech
Invest in reliability — outages are hidden shrinkage with very public consequences.
Close the loop
Feed realised shrinkage back into forecasts and hiring plans every month.
Frequently Asked Questions About Shrinkage
What's a "good" shrinkage number?
Context matters. Many centres land between 28% and 35% once you include leave, breaks, meetings, and typical unplanned loss.
Your mileage will vary — the right number is your honest, measured one, not a benchmark borrowed from someone else.
Does shrinkage include paid breaks?
Yes. If an agent isn't contact-available, it's shrinkage — regardless of the reason.
Does shrinkage include unpaid lunch?
No. Shrinkage is calculated on paid time only. If lunch is unpaid, it's excluded from the calculation.
Should I use the same shrinkage all year?
No. Seasonality, leave patterns, and training cycles change it. Track it monthly at minimum.
Is shrinkage the same as occupancy?
No. Occupancy measures how busy available agents are. Shrinkage measures how much paid time they're not available at all.
Does shrinkage differ between channels?
It can. Phone, email, chat, and social media have different interruption patterns, but shrinkage is still staff-based.
If agents work across multiple channels, their shrinkage applies to their total paid time — not per channel — unless you measure each channel with its own dedicated FTEs.
What's the difference between planned and unplanned shrinkage?
Planned shrinkage is predictable — leave, training, meetings. Unplanned is unexpected — sick leave, outages, urgent escalations.
Can shrinkage be negative?
Rarely. It happens if "available" time exceeds "required" time — usually from overstaffing against actual demand.
Where to Next
Final Thoughts: Shrinkage is Non-Negotiable in WFM Planning
Call centre shrinkage isn't a nice-to-know — it's the backbone of accurate staffing.
Model it honestly, plan to it rigorously, and update it frequently. Your queues, customers, and team will all thank you.
Remember the essentials: split planned from unplanned, calculate on paid time only, track it monthly rather than setting it once, and flip the formula (Scheduled = Required ÷ (1 − Shrinkage)) when you roster so you don't quietly under-staff.
Want a deeper dive with interval-level analysis and scenario planning? ACXPA Members can use the advanced calculator and the full toolkit in the WFM Hub.
