Call Center Service Level


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Table of Contents

Introduction to Call Center Service Level

In the industry of Call Center, performance metrics and resulting numbers are a challenging task faced by the managers. Theoretically one cannot understand the achievements in the field of the call center. The managers have come up with techniques to quantify the results. The results indicate the improvement or decline in the performance of the call center in clear numbers. 

In simpler terms, Call Center Service Level can be defined as: A number of services that can be measured provided to a customer in a defined time period. There still remains some confusion with different formulas and definitions. However, in a call center, managers mostly measure the percentage of inbound calls answered by agents in a set time period. 

Call Center Service Level1

How is Service Level calculated in a Call Center?

Calculating service level in a call center is debatable. The rate can change when a different formula is employed to calculate. Hence, the result is subjected to being manipulated.

The formula which is generally used to measure service level is based on 

X % of calls should be answered within Y seconds [ X/Y x 100%]

It is important to reach the desired Service Level set by the Call Center. Hence, service level should be quantified and met more frequently, than once a month.

Let’s understand how to calculate service level. Also, look at other formulas used in the industry of Call Center.

Call Center Service Level2

Formulas and Calculation of Service Level

To understand let’s take the following data 

Time Period: 30 Seconds

Calls answered

Calls abandoned

Calls answered within first 20 sec

Calls abandoned after 20 sec

Calls abandoned within 5 sec

1st Formula 

The simplest and widely used formula is the same as mentioned above

Number of calls answered in the time period/numbers of calls answered X 100%

However, you should take note that this formula does not take the number of abandoned calls into consideration.

2nd Formula

This formula takes the answered and abandoned calls into consideration for calculation. The calls abandoned within the threshold is deemed as positive

Calls answered in time period + calls abandoned in time limit / total calls answered + total calls abandoned X 100%

3rd Formula

In contrast to the 2nd formula, this one considers the abandoned calls as negative. 

Total calls answered in time limit/ total calls answered + total calls abandoned X 100%

4th Formula

This formula ignores the number of calls abandoned within the threshold. The calls abandoned after the set time period are considered to affect the result.

Total calls answered in time period / total calls answered + total calls abandoned after time period X 100%

5th Formula

This formula includes the short calls. For example, the number of calls abandoned within 5 seconds as mentioned in the data.

Total calls answered within time period + calls abandoned within a shorter time than time limit / total calls answered + total calls abandoned X 100%

Call Center Service Level3

Best Practice to Calculate Service Level for your Call Center

Service Level when calculated frequently and defined clearly can help the call center management to make a data-driven decision. However, it may be confusing to establish how to measure the Service Level for their Call Center.

Hence, the best practices you call follow are

Abandoned Calls: Decide how to consider the abandoned calls, should they be counted or ignored. 

Formula: Based on the kind of result you want and the kind of data you want to include, select your formula. Finding the ideal formula that works best for the objective of your call center would keep the calculation simple and provide clarity on the result. 

Time Interval: Depending on the volume of calls in your call center and the needs, decide the time interval. The time interval also impacts the result of service level.

Frequency of calculating Service Level: It is ideal to monitor the service level of your call center continuously. But, it may not be possible so you decide on the frequency of measuring service level that can effectively reflect the operation of your call center.

Decide Service Level: It is important for a business to establish a service level. The service level objective should involve customer expectations, wait time, needs, and other factors that affect customer satisfaction.

Data from different sources: It is essential that all the departments present their service level data. Different departments may have different volumes of calls and so, the formula used may end up being different. For instance, the billing department may have longer calls than inquiries about addresses. 

Right Tools: It is of utmost importance that your result is accurate in order to improve the performance of the call center.

Identify the reason for the slowdown: Service Level can have an impact due to longer calls, incorrect schedules, different call volumes, etc. it is important to figure out what the issues are and study them before designing an action plan.

Display results to all employees: Service Level is impacted by each and every employee that works in a call center. It should be displayed to the entire staff. This will help the agents understand the objective of the business and motivate them to achieve it.

Action and Adapt: You can’t collect data and not take necessary action. The management should take full advantage of the data and analyze it to formulate plans to improve the performance. 

Moreover, the industry of call centers is always changing. Therefore, the service goal should also be changed and adapted according to the market.

Hence, it is essential to find the right software that can process all the data. Also, the tool should help you in making proper adjustments in regard to your call center’s measurement.

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Industry Average
Service Level of Phone Calls

It has been a traditional standard for the entire call center industry to target answering 80% of calls within 20 seconds. 

However, many call centers are moving away from this standard. Some call centers choose to relax their target time, while there are call centers that have boosted it to a high percentage. 

Relax Answer Time: These contact centers may have identified that changing their SLA can impact their customer satisfaction. In the graph, these contact centers mostly show up around 70/20 and 80/60 data points.

However, if you want to follow this example, you need to ensure that you won’t lose too many calls. It is better to check the impact service level has on the abandoned calls in your call center before changing your SLA.

Boosting Service Level: Many call centers, on the other hand, seem to have researched more about their customer base. The call center has experimented and established how the customer satisfaction and abandon call rates vary when they change their service level. 

In different sectors, the customers waiting times may differ widely. It seems that these call centers are plotting the abandoned call rates against their set SLA and forming an abandon curve. Then depending on customer satisfaction, brand value, and staff, set the “abandon ceiling” of 2 and 5% to an SLA.

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The most common formula used by the call center industry to calculate Service Level is: 

Number of calls answered within time period/ total number of call answered X 100%

This is based on the objective of X% of calls answered with Y seconds. For example, the industry standard of 80% of calls answered within 20 seconds.

The service level of 80/20 is the traditional industry standard. This implies that the call center aims to answer 80% of calls within the first 20 seconds.

  • Decide how to consider abandoned calls
  • Establish a formula that suits the purpose
  • Decide the time-interval
  • Determine the frequency of calculating Service Level
  • Obtain data from different sources
  • Use right tools
  • Identify reasons for the slowdown
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