How many agents does it take to answer 100 calls per hour with a 6-minute average handle time?

You need 14 agents on the phones to hit an 80/20 service level, which delivers 86.1 percent of calls answered within 20 seconds at 71.4 percent occupancy. At 30 percent shrinkage, that means scheduling 20 agents to keep 14 seats filled during the hour.

How much does average handle time change staffing at 100 calls per hour?

At 100 calls per hour with an 80/20 target, a 3-minute AHT needs 8 agents on the phones, 4 minutes needs 10, 5 minutes needs 12, and 6 minutes needs 14. That works out to roughly one agent for every 30 seconds of handle time at this volume.

What happens if you staff fewer than 14 agents for 100 calls per hour at a 6-minute AHT?

With 13 agents the service level falls to 76 percent of calls answered within 20 seconds, below the 80/20 target. With 12 agents it drops to 60 percent, and the queue recovers slowly after any spike because little idle capacity remains to burn it down.

What is the offered load for 100 calls per hour at 360 seconds per call?

The offered load is 10 erlangs: 100 calls times 360 seconds, divided by the 3,600 seconds in an hour. Erlang C then requires 14 agents on the phones for an 80/20 service level, four more than the raw workload, because calls arrive randomly rather than in an even stream.

Is it cheaper to cut handle time or hire more agents at 100 calls per hour?

Cutting AHT from 6 minutes to 4 shrinks the requirement from 14 agents on the phones to 10, and from 20 scheduled to 15 at 30 percent shrinkage. If part of your 6 minutes is wrap-up, slow systems, or missing knowledge-base answers, each 30 seconds you remove is worth roughly one agent in every staffed hour, which usually costs less than adding permanent headcount.

The call center staffing ladder

Call center staffing

How many agents do you need for 100 calls an hour with a 6-minute handle time?

At this volume, every 30 seconds of average handle time is roughly one more agent on the phones.

The short answer

Handling 100 calls an hour at a 6-minute average handle time with an 80/20 service level takes 14 agents on the phones; at 30 percent shrinkage you schedule 20.

Calls per hour: 100
Offered load: 10 erlangs
Agents on phones: 14
Scheduled agents: 20
Service level hit: 86.1%
Occupancy: 71.4%

Why the math lands there

100 calls an hour at 360 seconds per call is 10 erlangs of offered load. Erlang C puts 14 agents on the phones against an 80/20 target, which lands at 86.1 percent of calls answered within 20 seconds and 71.4 percent occupancy. The margin below that is thin: 13 agents deliver a 76 percent service level and 12 agents deliver 60 percent. At 30 percent shrinkage, keeping 14 seats filled means scheduling 20 agents.

Compare that with the same 100 calls at a 4-minute AHT: 10 agents on the phones and 15 scheduled. Two extra minutes of handle time cost 4 more agents in every staffed hour and 5 more on the schedule, a 40 percent bigger team for the identical call count. The full sensitivity at this volume runs 8 agents at a 3-minute AHT, 10 at 4 minutes, 12 at 5, and 14 at 6. Every 30 seconds of handle time is worth roughly one agent.

That is why the 6 minutes deserves an audit before the headcount request does. Some products genuinely need long conversations, and if yours does, staff the 20. But wrap-up spent retyping notes into a second system, slow CRM screens, and answers agents have to hunt for are staffing costs wearing a process disguise. At this volume, removing 30 seconds of waste is worth about one agent in every hour you operate.

1100 calls an hour times 360 seconds of handle time is 10 erlangs of offered load: 10 hours of phone work arriving every hour.
2Counting up from 10 agents, 14 is the first count where Erlang C clears the 80/20 target: 86.1 percent of calls answered within 20 seconds, with an average wait of 15.7 seconds.
3At 14 agents, occupancy is 71.4 percent: the share of each logged-in hour spent handling calls rather than waiting for the next one.
4Breaks, meetings, training, and absence take agents off the phones for 30 percent of paid time, so keeping 14 on the phones means scheduling 20.

One agent either way

Erlang math is a cliff, not a slope. This is the same hour with one or two agents more or fewer on the phones.

Agents on phones	Answered in 20s	Average wait	Occupancy
12	59.8%	80.9s	83.3%
13	75.9%	34.2s	76.9%
14the answer	86.1%	15.7s	71.4%
15	92.3%	7.3s	66.7%
16	95.9%	3.4s	62.5%

If your handle time or target differs

Agents on the phones for 100 calls an hour, across handle times and the two most common service level targets. Adjust every input live in our Erlang C calculator.

Average handle time	80/20 target	90/30 target
3 minutes	8 agents	9 agents
4 minutes	10 agents	11 agents
5 minutes	12 agents	13 agents
6 minutesthis page	14 agents	15 agents

Scheduled headcount sits above every number here: this page assumes 30 percent shrinkage, and your own rate comes out of our shrinkage tool.

What Erlang C does not tell you

Erlang C takes the 6-minute AHT as a stable average, but long averages usually hide wide variance. A queue that mixes short password resets with long troubleshooting calls can average 6 minutes while behaving worse than the model predicts, because a cluster of long calls ties up several of the 14 agents at once and the queue drains slowly behind them. The higher the AHT, the more damage a bad mix of arrivals does to intervals the average says you can handle.

There is also a bootstrapping problem in hiring your way out. The 5 extra scheduled agents this AHT demands will themselves handle calls slower than 6 minutes while they ramp, which pushes the true on-phone requirement above 14 until they are fully productive. Going the other way has a cost too: an AHT-reduction program runs on coaching and training hours, which come out of shrinkage, so the 30 percent assumption and the 20 scheduled heads are both temporarily light while you fix the handle time.

Check what your 6 minutes actually measures before trusting any of these numbers. AHT here means talk plus hold plus wrap-up. Many phone system reports show talk time only and log after-call work separately, and at this volume the difference is not rounding: the sensitivity above says every 30 seconds you failed to count is roughly one missing agent. A 6-minute plan built on a talk-only report is understaffed by whatever the wrap-up really is.

The agent count is the input; the schedule is the work. Turning 20 scheduled agents into shifts that follow your call curve, respect breaks, and survive swaps is what Soon builds automatically, with intraday coverage tracking when the forecast misses.

Frequently asked questions

How many agents does it take to answer 100 calls per hour with a 6-minute average handle time?: You need 14 agents on the phones to hit an 80/20 service level, which delivers 86.1 percent of calls answered within 20 seconds at 71.4 percent occupancy. At 30 percent shrinkage, that means scheduling 20 agents to keep 14 seats filled during the hour.
How much does average handle time change staffing at 100 calls per hour?: At 100 calls per hour with an 80/20 target, a 3-minute AHT needs 8 agents on the phones, 4 minutes needs 10, 5 minutes needs 12, and 6 minutes needs 14. That works out to roughly one agent for every 30 seconds of handle time at this volume.
What happens if you staff fewer than 14 agents for 100 calls per hour at a 6-minute AHT?: With 13 agents the service level falls to 76 percent of calls answered within 20 seconds, below the 80/20 target. With 12 agents it drops to 60 percent, and the queue recovers slowly after any spike because little idle capacity remains to burn it down.
What is the offered load for 100 calls per hour at 360 seconds per call?: The offered load is 10 erlangs: 100 calls times 360 seconds, divided by the 3,600 seconds in an hour. Erlang C then requires 14 agents on the phones for an 80/20 service level, four more than the raw workload, because calls arrive randomly rather than in an even stream.
Is it cheaper to cut handle time or hire more agents at 100 calls per hour?: Cutting AHT from 6 minutes to 4 shrinks the requirement from 14 agents on the phones to 10, and from 20 scheduled to 15 at 30 percent shrinkage. If part of your 6 minutes is wrap-up, slow systems, or missing knowledge-base answers, each 30 seconds you remove is worth roughly one agent in every staffed hour, which usually costs less than adding permanent headcount.

How many agents do you need for 100 calls an hour?

10 agents on the phones, 15 on the schedule, and a service level cliff hiding one absence away.

10 on phones · 15 scheduled · 80/20

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How many agents do you need for 100 calls an hour at a 90/30 service level?

11 agents on the phones, 16 scheduled at 30 percent shrinkage, and only one more head than the same line at 80/20.

11 on phones · 16 scheduled · 90/30

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How many agents do you need for 200 calls an hour?

17 agents on the phones, 25 on the schedule, and exactly one point of margin over the 80/20 target.

17 on phones · 25 scheduled · 80/20

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