Contact Center Workforce Management: Beginner’s Guide
By DialPhone Team
TL;DR: Workforce management (WFM) is the process of forecasting contact volume, creating agent schedules to match demand, and monitoring real-time adherence. Good WFM reduces labor costs by 15-25% while maintaining service levels. This guide covers the fundamentals for contact centers implementing WFM for the first time.
What Is Workforce Management?
Workforce management answers a deceptively simple question: how many agents do you need, and when?
The answer is complex because customer demand fluctuates throughout the day, week, month, and year. Monday mornings look nothing like Friday afternoons. January differs from July. A product launch week is nothing like a quiet week in August.
WFM encompasses four core activities:
- Forecasting — Predicting how many interactions (calls, chats, emails) you will receive in each time period
- Scheduling — Creating agent work schedules that align staffing with forecasted demand
- Real-time management — Monitoring actual performance vs. plan and making adjustments
- Reporting and optimization — Analyzing results to improve future forecasting and scheduling
Why WFM Matters
Labor is the largest expense in any contact center, typically accounting for 65-75% of total operating costs. WFM directly controls how efficiently that labor is used.
Consider a 50-agent contact center with an average fully-loaded agent cost of $22/hour:
- Without WFM: Overstaffing by 10% costs $22 x 50 x 0.10 x 8 hours x 260 working days = $228,800/year wasted. Understaffing by 10% during peak hours causes 15% abandonment, driving customers to competitors.
- With WFM: Staffing aligns within 3-5% of optimal, saving $100,000-$200,000/year while maintaining service levels.
Step 1: Forecasting
Gather Historical Data
Effective forecasting requires at least 3-6 months of historical contact volume data, ideally 12-24 months. You need this data at the interval level — typically 15 or 30 minutes — not just daily or monthly totals.
Required data points:
- Number of contacts received per interval, by channel
- Average handle time per interval
- Abandonment rate per interval
- Day-of-week patterns
- Seasonal trends
DialPhone’s contact center platform captures all of this data automatically.
Identify Patterns
Contact volume follows predictable patterns:
Daily pattern: Most contact centers see volume ramp up from 8-9 AM, peak between 10 AM-12 PM and 1-3 PM, and taper after 4 PM. Mondays are typically the highest-volume day (20-25% above average), while Fridays are the lowest (15-20% below average).
Monthly pattern: Billing cycles create monthly peaks. If invoices go out on the 1st, expect higher volume on the 2nd through 5th.
Seasonal pattern: Retail peaks in Q4. Tax services peak in Q1. Travel peaks in summer. Your industry has its own seasonality.
Event-driven spikes: Product launches, marketing campaigns, outages, and PR events cause unpredictable volume increases. Build a calendar of known events and their estimated volume impact.
Create the Forecast
For beginners, a straightforward approach:
- Calculate average volume by interval across the past 8-12 weeks
- Apply day-of-week adjustments (Monday factor, Tuesday factor, etc.)
- Apply seasonal adjustment based on year-over-year comparison
- Layer in known events (marketing campaigns, product launches)
- Review and adjust based on recent trends (is volume growing, declining, or flat?)
For more advanced forecasting using AI and machine learning, see our guide on AI workforce management.
Forecast Validation
Measure forecast accuracy weekly: (1 - |Actual Volume - Forecasted Volume| / Actual Volume) x 100. Target 90%+ accuracy at the daily level and 85%+ at the interval level.
Step 2: Staffing Calculation
Once you know how many contacts to expect, calculate how many agents you need to handle them at your target service level.
The Erlang C Formula
The industry-standard staffing model is Erlang C, which calculates the probability that a call will wait given a specific number of agents, call volume, and average handle time.
Inputs:
- Number of contacts per interval
- Average handle time (AHT)
- Target service level (e.g., 80% of calls answered within 20 seconds)
The formula is mathematically complex, but DialPhone’s WFM tools calculate it automatically. For manual planning, free online Erlang C calculators are available.
Account for Shrinkage
The Erlang C output tells you how many agents need to be on the phones. But agents are not on the phones 100% of their shift. Shrinkage accounts for breaks, lunches, training, meetings, coaching sessions, bathroom breaks, and unplanned absences.
Typical shrinkage: 25-35%
If Erlang C says you need 30 agents on the phones at 10 AM, and your shrinkage is 30%, you need 30 / 0.70 = 43 agents scheduled for that period.
Occupancy Guard Rails
After calculating staffing, check the resulting occupancy rate. Occupancy = (Total handle time / Total available time) x 100. If occupancy exceeds 85% for sustained periods, you are understaffed. Agents will burn out, quality will drop, and turnover will spike. Add staff until occupancy falls into the 75-85% range.
Step 3: Scheduling
Scheduling is the art of matching agent availability to staffing requirements while respecting business rules and agent preferences.
Schedule Types
Fixed schedules: Agents work the same shifts every week (e.g., Monday-Friday 8 AM-4 PM). Simple to manage but inflexible — cannot match varying demand across the week.
Rotating schedules: Agents cycle through different shift patterns (e.g., Week 1: mornings, Week 2: afternoons). More flexible but more complex to manage.
Flexible schedules: Agents have core hours with flexibility around start and end times. Best for remote teams and newer workforce expectations.
Split shifts: Agents work two shorter shifts in a day (e.g., 8 AM-12 PM and 4 PM-8 PM). Efficient for covering peaks but unpopular with agents.
Schedule Optimization Tips
- Stagger start times: Instead of all agents starting at 8 AM, stagger starts every 30 minutes (7:30, 8:00, 8:30, 9:00). This smooths coverage across the day.
- Schedule breaks during valleys: Place lunches and breaks during historically low-volume periods.
- Use part-time agents for peaks: Supplement full-time agents with part-time staff for the 2-3 hour daily peak.
- Allow shift swaps: A self-service shift swap marketplace reduces last-minute schedule changes and improves agent satisfaction.
Step 4: Real-Time Management
No forecast is perfect. Real-time management adjusts to actual conditions as they unfold.
Monitor in Real Time
Watch these metrics continuously during operating hours:
- Actual volume vs. forecast
- Service level (current and rolling)
- Agents available vs. required
- Queue depth and longest wait time
- Adherence to schedule
DialPhone’s real-time dashboards provide all of these views with automatic alerting when thresholds are breached.
Intraday Adjustment Playbook
When volume is higher than forecast:
- Recall agents from offline activities (training, meetings) that can be rescheduled
- Extend shifts (ask for voluntary overtime)
- Reduce after-call work time targets
- Enable overflow routing to another team or AI
- Activate callback queue (offer callers a callback instead of waiting)
When volume is lower than forecast:
- Move up scheduled training and coaching sessions
- Allow early departures (voluntary time off)
- Pull forward offline tasks (email backlogs, quality reviews)
- Use the downtime for 1-on-1 coaching
Step 5: Reporting and Continuous Improvement
Weekly WFM reporting should include:
- Forecast accuracy (by day and by interval)
- Service level achievement vs. target
- Schedule adherence rates
- Occupancy and utilization
- Overtime hours and cost
- Shrinkage breakdown by category
Use this data to refine your forecasting models, adjust scheduling practices, and identify structural issues. If you consistently under-forecast Mondays, increase your Monday adjustment factor. If adherence is low after lunch, investigate whether break scheduling is the issue.
Tools and Technology
For contact centers under 20 agents, spreadsheet-based WFM is manageable if tedious. Above 20 agents, dedicated WFM tools become essential. Above 50 agents, AI-powered WFM delivers significant ROI.
DialPhone’s AI Workforce Management is integrated directly into our contact center platform, providing automated forecasting, schedule optimization, real-time adherence monitoring, and intraday management in a single solution.
Getting Started
If you are new to workforce management, start simple:
- Collect 4-6 weeks of interval-level volume data
- Calculate average volume by interval and day of week
- Use an Erlang C calculator to determine staffing needs
- Build a basic schedule with staggered starts
- Monitor service levels daily and adjust
Then graduate to automated WFM tools as your contact center grows. Start a free trial of DialPhone to access integrated workforce management alongside your contact center platform.
The DialPhone team serves over 500,000 businesses in 46+ countries. Learn more.