20 call centre metrics and KPIs to enhance the CX

Inbound call centres are the backbone of excellent phone support. They are often the first human contact point for customers and must be helpful, efficient, and knowledgeable to promote an outstanding customer experience (CX). But skilled teams don’t manifest out of the blue—managers need to use call centre metrics to ensure their support agents are trained properly and operating at peak performance.

From first call resolution to first response time, we’ve compiled the 20 most important metrics you need to track.

More in this guide:

• Why track call centre metrics?
• Customer experience metrics
• Agent performance metrics
• Call centre operations metrics
• How to improve call centre metrics
• Frequently asked questions
• Improve your call centre metrics with Zendesk

Why track call centre metrics?

Businesses should track call centre metrics because they provide actionable insights teams can use to improve operations. A few benefits of doing so include:

• Improved customer satisfaction: Metrics like Customer Effort Score and customer satisfaction (CSAT) scores can give valuable insights into team performance and what you can do to improve. This can help you improve customer service processes to boost satisfaction.
• Optimised agent performance: Call centre agents may field hundreds of calls per day. Keeping an eye on figures like adherence to schedule and total resolution time can help you identify top performers and employees who need additional training.
• Reduced operational costs: The more efficient your team is, the lower your operational costs will be. Metrics like average handle time and call abandonment rate can pinpoint inefficiencies in your processes—empowering you to optimise your labour budget, adopt time-saving technology, and more.

When businesses track call centre metrics, they can make informed decisions to improve CX and their bottom line.

Customer experience metrics

A support agent may feel like they had a good phone call with a customer, but you can’t fully gauge the experience from their opinion alone. Monitor these CX metrics and customer service KPIs to understand how your customers are feeling.

1. CSAT scores

Customer satisfaction (CSAT) scores indicate your customers' satisfaction with a purchase or support interaction. You can calculate CSAT using customer satisfaction surveys, asking questions like:

• Were you satisfied with ___? (Yes/No)

• On a scale of 1–10, how satisfied are you with ___?

• How would you rate your satisfaction with ___? (Unsatisfied, Somewhat Satisfied, Very Satisfied)

To find your CSAT score, divide all positive responses (e.g., “somewhat satisfied” and “very satisfied”) by the total responses received. Then, multiply that result by 100.

2. First call resolution (FCR)

First call resolution, often called first contact resolution, is the percentage of support tickets agents resolve in the first interaction. This could mean they solve a problem with one phone call, a single email response, or a live chat conversation. Tracking FCR allows you to understand how well your customer support team meets customer expectations.

3. Net Promoter Score® (NPS)

The Net Promoter Score® (NPS) measures customer loyalty. This metric is about long-term satisfaction and is calculated via a survey, which you should send quarterly or bi-quarterly.

An NPS survey asks a single question: “How likely are you to recommend this company to a friend or colleague?” and provides a rating scale of 0–10. It’s also important to leave a comment box where customers can elaborate on the score they chose.

Customer responses are categorised into three groups:

• Promoters are customers who respond with a 9 or 10 rating. They are considered loyal customers likely to buy again and provide referrals.
• Passives are customers who leave a rating of 7 or 8. The customers are satisfied with your brand but could be swayed by competitors.
• Detractors are customers who answer 6 or below. These are unhappy customers at risk of spreading negative reviews of your product or service.

4. Customer Effort Score (CES)

Customer Effort Score measures the effort it takes for a customer to get what they need from your company—whether that’s resolving an issue, finding an answer to a question, or completing a specific action. For call centres, CES reveals how much effort customers put in to reach a support agent to get their issues resolved.

To determine CES, conduct a survey to ask customers about the ease of their interaction. The response choices should range from “very easy” to “very difficult.” Once you have the survey results, add up the ratings and divide the sum by the total number of responses.

A high CES may point to a problem with your team’s communication processes or tools. To lower it, make it easier for customers to connect with agents by offering contact options beyond the phone, such as live chat, email, and messaging. Providing self-service resources—including an FAQ page, knowledge base, and AI agents—empowers customers to solve basic issues on their own and also reduces the effort they have to expend.

Agent performance metrics

Agent performance shouldn’t be “good” or “bad.” Instead, evaluate the effort agents put in and how they resolve customer issues to get a holistic view of performance.

5. Agent effort score

Agent effort score (AES) measures how easy it is for agents to support their customers. AES pinpoints where agents meet challenges that hinder them from delivering top-notch support experiences—and it’s the only call centre metric that gives insight into agent performance from the agent’s perspective.

To calculate AES, send agents a survey asking them to rank how easy it is for them to support customers. Then, add up those scores and divide the sum by the number of respondents.

6. First response time (FRT)

First response time, or first reply time, measures how long it takes for a support agent to respond to a customer request. Calculate this metric by dividing the total of all first response times by the total number of calls—but make sure to exclude calls that come in after business hours.

A high average first response time could suggest that agents are handling too many calls. To provide faster support to callers, consider increasing the number of agents available during peak hours. You could also invest in AI-powered phone support like Zendesk Voice. Our capabilities empower you to use AI agents to answer calls, solve sophisticated interactions, and transfer callers to human agents when necessary. This can dramatically reduce your FRT and help customers solve their issues faster.

7. Wrap-up time

When an agent ends a call with a customer, it doesn’t mean their job is done. They still have to perform tasks like escalating complaints, assigning tickets to other departments, or sending follow-ups to ensure the ticket is completely resolved. Wrap-up time is the amount of time it takes an agent to finish these activities after a call.

To calculate this metric, subtract the total hold time and total talk time from the total amount of handle time. Then, divide that result by the total number of customer calls. If it’s too high for your liking, consider automating post-call activities with CRM software.

8. Call abandonment rate

Call abandonment rate is the total number of customers who hang up while waiting to speak with an agent. Calculate this metric by taking the difference between the number of calls received and the number of calls handled, then divide that by the number of calls received. Multiply that number by 100 to get your percentage.

If your call abandonment rate is too high, you can start by allowing customers to request a callback. This way, customers can keep their place in line without remaining on hold, and an agent will call them when it’s their turn.

9. Total resolution time

Total resolution time measures the average time it takes for support agents to resolve a customer issue. To calculate the total resolution time, divide the total time of all resolved interactions by the total number of tickets solved.

When faced with a high total resolution time, investigate what may be slowing agents down. For example, if they are having excessive back-and-forth conversations, agents might not have enough customer details, or there might be problems with your product or service.

10. Transfer rate

Transfer rate is the percentage of inbound calls that agents end up transferring to another team member or department. To calculate it, divide the total number of calls transferred to another department or agent by the total number of calls handled. Then, multiply the result by 100.

A high transfer rate could indicate that callers are reaching the wrong agent. In this case, your interactive voice response (IVR) system could be to blame. However, if the IVR is working properly and the transfer rate is still high, measure the average transfer rate across the entire call centre. Look for any outliers—like agents who routinely surpass the average percentage—to identify employees needing additional training or resources.

11. Agent utilisation rate

Agent utilisation rate is the average time a rep spends on customer calls during their designated work hours. This metric assesses productivity and determines whether an agent is using their time well.

You can improve agent utilisation rate through refresher call centre training to help customer support agents better understand customer issues and how to solve them. You should also consider investing in tools like a CRM, which can consolidate customer communication and interactions from all channels into one unified view.

12. Adherence to schedule

Adherence to schedule is the percentage of time that employees are on the clock vs. their scheduled hours. This metric is especially important for call centres with limited staff, where offline employees make a larger impact on the workflow.

Say your support team consists of only 20 agents, three of whom come in 15 minutes late. For those 15 minutes, 15 percent of your team is offline. This could increase hold times and frustrate customers. To improve adherence to schedule, consider workforce management tools like Zendesk WFM. With WFM, you can improve productivity, track agent activity in real time, and use AI to create optimised employee schedules.

13. Calls answered per hour

This simple metric shows you how many calls each agent answers per hour. This number can waver, however, depending on shift changes, seasonal call volumes, training, and more.

While this metric is important, avoid overemphasising it with your team. If your company pushes this metric, your agents will focus on the number of calls they take rather than on the quality of service they’re providing to the customer. Instead, invest in tools like an effective CRM that helps agents find information faster and work more efficiently.

14. Average handle time (AHT)

Average handle time measures the average duration of a customer service interaction. Tracking this metric allows you to determine average handle times for different types of calls and set standards for your team.

Reconciling this metric can be tricky—your agents should find a balance between speed and great customer service. Agents who regularly exceed the AHT benchmarks may not address all the customer’s needs, whereas agents who have longer AHTs may not have the skills or tools to handle customer issues in a timely manner.

Call centre operations metrics

Call centre operations metrics help companies understand call centre performance over time. Tracking these KPIs is crucial for executives to identify peak times, spot trends, and forecast staffing needs.

15. Calls handled

Calls handled refers to the calls answered over a designated timeframe. This metric doesn’t typically include abandoned or dropped calls. Most companies calculate this KPI in two ways:

• Total number of calls an agent handles in a period

• Total number of calls an IVR system handles in a period

16. Cost per call (CPC)

Cost per call (CPC) tracks the average cost of each call handled by a call centre agent. This KPI is important because it provides insight into the cost-effectiveness of your call centre operations and drives resource allocation.

Calculate CPC by taking the total cost of all calls and dividing that number by the total number of calls. If you want to improve CPC, you can start by utilising a remote work model, improving training, or investing in a cloud-based CRM.

17. Call arrival rate

Call arrival rate is the number of incoming calls in a designated time frame.

Depending on which trends your operations management team finds to be the most beneficial, you can evaluate call arrival rate daily, hourly, or minute-by-minute.

18. Average age of query

The average age of query measures the average length of time unresolved customer queries stay open. Issues that agents resolve upon first contact aren’t included in this metric. Average age of query gives the call centre insight into the length of time it takes agents to resolve difficult issues.

If you experience a high average age of query, it could mean that agents need better tools or training to address complicated queries. Consider CRM software that can automatically route complex queries to the appropriate agents best suited to resolve them.

19. Service level

Your call centre should have customer service standards like a service level agreement (SLA)—a set of standards you use to manage expectations, guide decisions, improve customer satisfaction, and more. Most companies have similar service level rate standards, such as:

• Answering 90% of calls within 20 seconds (or four rings)

• Responding to 80% of chats within 20 seconds

• Responding to 100% of emails within eight hours

The service level call centre formula is simply the total number of calls answered within the set threshold time limit divided by the number of calls offered. Then, multiply that number by 100 to get your percentage.

20. Repeat call rate

Repeat call rate is the percentage of customer calls that address an established issue. Tracking repeat calls and collecting customer feedback can reveal recurring issues, enabling management teams to find resolutions and prevent the problems from happening again.

If you are struggling in this metric, work to identify recurring issues that cause customers to call back for the same problem—it may be due to agent training gaps and insufficient call centre skills. Investigating this metric could also lead management to incorporate solutions into self-service options so customers can help themselves rather than wait to speak with an agent.

How to improve call centre metrics

While we have sprinkled in a few tips to improve metrics in their respective sections, you can also take an all-encompassing approach. Follow these tips to improve your figures across the board.

Evaluate your current performance

Before you hone in on any metric in particular, you need to gain a complete view of your current performance. Dig into customer satisfaction, agent performance, and operations data to discover areas of improvement.

Additionally, it is important to consult with call centre agents and managers to get their input on current performance and see if they see any opportunities for improvement from their perspective. This combination of data and employee experiences can give you a complete view of your operation’s strengths and weaknesses.

Define your end goals

After evaluating performance, set clear, measurable goals to give your team a roadmap for improvement. Consider adopting the SMART approach to help you reach your benchmarks as efficiently as possible. For example, if you wanted to increase first response time, a SMART goal could be, “Improve FRT by 5% by Q3 by optimising agent schedules and investing in technology like AI agents”.

Monitor progress over time

While you shouldn’t obsess over your goals daily, check in periodically to monitor progress. For example, if you set a goal with an end date of next quarter, consider evaluating your progress halfway through. This can help you see how you are progressing and allow you to make tweaks to help you hit your goal.

Spot training and efficiency opportunities with AI

Embracing AI in customer service quality assurance (QA) can help you identify roadblocks in your CX and spot areas where agents need additional training. This can help you pinpoint areas of improvement that you could have missed on your own.

For example, tools like Zendesk QA automatically review 100% of support interactions. This gives valuable insight into agent performance, automatically flags bottlenecks in your operations, and can identify customer churn risk, outliers, and escalations.

Review and improve

Once you’ve reached the end of your time-bound KPI goal, evaluate what went right—and what went wrong. If you fell short in improving one of your metrics, try to pinpoint why and use that information to inform future goal-setting. Conversely, if you succeeded in your efforts, try to determine what helped your success so you can apply that to future improvements.

Frequently asked questions

Improve your call centre metrics with Zendesk

Call centre metrics can help you track agent performance and ensure you meet customer expectations—and the technology you use to field customer calls can be just as important to team productivity. At Zendesk, we offer comprehensive voice support for the AI era. We can help you boost CSAT, resolve calls with automation, and use AI to finish calls faster.

And if you’re looking to improve your customer experience beyond the dial tone, check out how our customer service software can revolutionise your help center operations.

Net Promoter, Net Promoter Score and NPS are registered trademarks of Satmetrix Systems, Inc., Bain & Company, Inc. and Fred Reichheld.