How to Calculate Required FTE for Inbound Call Volumes

Getting the right number of staff to meet inbound call demand is important to prevent long wait times and abandoned calls. 

But how do you calculate the required FTE for inbound call volumes?

Janet asked our Community of industry professionals this:

“I wanted to get feedback on how actual required FTE is being calculated by others for inbound call volumes.

I’m including occupancy in Forecasted FTE required, to account for a call centre environment in which its not realistic that an agent can handle calls back to back.

When calculating actual FTE required, historically the model has utilised actual occupancy in the calculation of FTE required. However I believe this inaccurately inflates the requirement.

However not accounting for occupancy in the requirement generates a misleading FTE number since the business would never run at 100% occupancy.“

And we wanted to share their responses with you.

Tips to Calculate Required FTE

How to Work out How Many Staff You Need in a Contact Centre

We have a great article that provides a step by step look at how many staff you need in your contact centre, and is a great starting point: How to Calculate Staffing in a Contact Centre

Use an Erlang Calculator

A useful tool is the Call Centre Helper Erlang Calculator

The Erlang Calculator also has a weekly planner.

Look At Forecast Accuracy

If it is a forecast then it will be wrong. That is the nature of forecasting as explained in this video:

You need to start tracking your forecast accuracy to see what your forecast accuracy is, so read this article about calculating forecast accuracy: How to Calculate Forecast Accuracy

You can then model it to see if there is a better value. A lot depends on averages. If you use an average occupancy figure for the year, then you may well find monthly variances – as more people take holiday during the summer and more people get ill during the winter.

Calculate Shrinkage

Don’t forget to factor in shrinkage!

This article walks through all the steps on how to calculate shrinkage. It should help: What is Call Centre Shrinkage and How to Calculate It?

Contributed by: Jonty

How to Determine How Many FTE Needed

adnan also asked our community how to determine how many FTE they needed:

I need some help calculating FTE needed for an activity:

• Volume per month = 177,
• Handle Time = 174 seconds
• 1 agent works 160 hours per month
• 28% of that time is shrinkage – therefore productive time is 115.2.

And so we’ve put together the responses to help you.

Tips to Calculate Required FTE Based on Volume

Break the Monthly Volume Down into Days

You need to break the monthly volume down into days (it is not evenly spread across the month) and use an Erlang Calculator.

The answer will probably work out as between 1 and 2 FTE.

Don’t Assume All Tasks Are Evenly Distributed Across the Day

Don’t assume that all tasks are evenly distributed across the day. This is not the case and will leave you understaffed.

You need to factor in your desired service level and use an Erlang Calculator.

Contributed by: Jonty

Annual FTE Calculation

Another reader, Andrea, posed a question about annual FTE calculations:

The problem is how much FTE needed if you want to increase active selling ratio to %30 in 1 year. I will try to calculate is it feasible to make an IT investment (250,000 USD one time and regularly 5,000 USD) or not?

What is the feasible amount to decide open a web sale channel or not?

• 1,000,000 calls
• %10 active selling
• 252 days
• 8 hours with %50 efficiency
• Annual FTE cost 50,000 USD
• AHT is 3400 seconds as an last information

Help for Annual FTE Calculation

Break It Down Into Days and Hours

You need to break it down into days and hours and then put it into an Erlang Calculator.

Contributed by: Jonty

This article was made possible due to the great community of experts we have at Call Centre Helper, to get involved just join our LinkedIn Community and and if you aren’t already make sure you are following us on LinkedIn to see our latest content.

You may also find these articles helpful to read next:

• Erlang Calculators Explained
• How to Calculate Occupancy in the Contact Centre
• How to Calculate FTE Requirements

Reviewed by: Megan Jones