# ACD Routing Strategies Explained: Round Robin, Longest Idle, Least Occupied and Skill-Based (2026)

> How an automatic call distributor picks the agent for each call, what round robin, longest idle, least occupied and skill-based routing actually do, and how to choose one for your queue.

Source: https://edesy.in/blog/acd-routing-strategies-explained-2026

**ACD routing decides which agent gets the next call. Round robin rotates through agents in order; longest idle
picks whoever has waited longest since their last call; least occupied aims for the lightest load; skill-based
picks an agent with the skill the queue needs. Choose per queue, based on how alike your calls are.**

> **Set up a queue:** [Open the Edesy contact center](https://ccaas.edesy.in/?utm_source=edesy.in&utm_medium=blog&utm_campaign=acd-routing-strategies-explained-2026). Once your agent seats are provisioned, add skills, create a queue and pick its routing strategy.

## How ACD works, step by step

1. A call reaches a number attached to a queue.
2. The caller hears music on hold while the ACD looks for an agent.
3. The ACD takes the agents who are **available** (not on a call, on break, in wrap-up or offline).
4. The queue's routing strategy picks one.
5. That agent's browser softphone rings. If they don't answer, the call moves to the next agent.
6. When the call ends, the agent goes into wrap-up and picks a disposition.

The strategy is only step 4, but it shapes how fair the workload feels and how fast callers reach the right
person.

## The four strategies

| Strategy | How it picks | Best when | Watch out for |
|---|---|---|---|
| Round robin | Next agent in a fixed rotation | Calls are similar and short; you want predictability | Agents who get long calls fall behind on rest time |
| Longest idle | Available agent who has gone longest since their last call | One team, one kind of call; you want even workload | Doesn't consider skills |
| Least occupied | Agent with the lightest recent load | Agents share a queue but call lengths vary a lot | On Edesy it currently picks the same way as longest idle |
| Skill-based | Agent with the queue's required skill and minimum level | Callers need a language, product or tier | Too many narrow skills can leave calls waiting |

### Round robin

Agents take turns. Agent A, then B, then C, then back to A. It is easy to explain and easy to audit. The
weakness: rotation counts calls, not minutes. If A gets a 20-minute call and B gets a 2-minute one, B is back in
the rotation much sooner relative to their workload.

### Longest idle

The next call goes to whichever available agent finished their last call longest ago; agents who haven't taken a
call yet come first. Because it looks at time rather than turn order, it spreads work more evenly when call
lengths vary. For a single support or sales team, it is a sensible default.

### Least occupied

The idea is to route to the agent who has spent the least time busy, so the load evens out across a shift. On
Edesy today, least occupied selects agents the same way as longest idle; a separate occupancy calculation is not
in place yet. If even workload is your goal, longest idle gives you that now.

### Skill-based

You give agents skills (Hindi, Tamil, billing, enterprise accounts) with a level, and set a queue's required skill
and minimum level. The ACD picks among available agents who have that skill at that level, choosing the one who
has been idle longest. If no skilled agent is free, it falls back to any available agent, so callers aren't stuck
waiting for one person.

Language is the most common skill in India. Separate Hindi and Tamil queues, each requiring its language skill,
usually beat one big queue where a Tamil caller might reach a Hindi-only agent.

## Choosing a strategy

| Your situation | Start with |
|---|---|
| One team, one kind of call | Longest idle |
| Short, uniform calls; simple audit trail | Round robin |
| Callers need different languages | Skill-based, one skill per language |
| Sales tiers (new leads vs key accounts) | Skill-based |
| Mixed call lengths, shared queue | Longest idle |

Two rules that matter more than the strategy:

- **Keep agent statuses accurate.** Every strategy only picks from "available" agents. An agent who leaves their
  desk without going on break gets rung, misses the call, and the caller waits longer.
- **Don't over-split skills.** Ten skills with two agents each means long waits for some callers while other
  agents sit idle. Start broad and split only when the data says so.

## What to measure after you choose

The supervisor dashboard shows agents by state (available, on call, on break, wrap-up, offline), calls waiting,
longest wait, service level (the share of calls answered within 20 seconds), abandoned calls, average handle time
(AHT) and average wait. Watch:

- **Longest wait and abandoned calls** per queue: a skill set too narrow shows up here first.
- **AHT per agent:** large gaps suggest training needs, not a routing problem.
- **Missed rings per agent:** a sign of status discipline issues.

For formulas, see [call center KPI formulas](https://edesy.in/blog/call-center-kpi-formulas-aht-fcr-abandonment-shrinkage-2026).

## Setting it up on Edesy

1. Agent seats are provisioned with the Edesy team ([talk to us](https://edesy.in/contact)). Agents then appear in
   [ccaas.edesy.in](https://ccaas.edesy.in/?utm_source=edesy.in&utm_medium=blog&utm_campaign=acd-routing-strategies-explained-2026).
2. Create skills and assign them to agents with a level.
3. Create a queue, choose the routing strategy, and set the required skill if you use skill-based routing.
4. Set music on hold.
5. Attach a number to the queue.
6. Agents log in to the browser softphone at ccaas-agent.edesy.in and set themselves available.
7. Place a test call and watch it on the supervisor dashboard.

## Pricing

| Plan | Per agent per month | Agents | Notes |
|---|---|---|---|
| Starter | Rs 1,500 | Up to 20 | |
| Professional | Rs 2,500 | Up to 100 | Skill routing, IVR builder, advanced analytics, API access |
| Enterprise | Rs 3,500 | Unlimited | |

Call minutes are extra at the voice rate (Rs 0.50/min, 60-second pulse, unanswered calls free). Prices exclude
18% GST. See [contact center pricing](https://edesy.in/cloud-contact-center/pricing) and the
[per-agent pricing explainer](https://edesy.in/blog/per-agent-call-center-pricing-explained-india-2026).

More on the [cloud contact center](https://edesy.in/cloud-contact-center) page and in the [contact center docs](https://edesy.in/docs/contact-center).

## Frequently Asked Questions

### What is ACD routing?

ACD (automatic call distribution) is the part of a contact center that decides which available agent gets each incoming call. A routing strategy is the rule it uses, such as rotating through agents, picking whoever has waited longest, or matching the caller to an agent with the right skill.

### Which ACD strategy is best?

There is no single best. Longest idle is a fair default for one team handling one kind of call. Skill-based is better when callers need different expertise, such as language or product. Round robin is simple and predictable. Pick per queue, not for the whole center.

### What is the difference between round robin and longest idle?

Round robin hands calls to agents in a fixed rotation. Longest idle gives the next call to the available agent who has gone longest since their last call, which spreads work more evenly when calls vary in length.

### What happens if the chosen agent doesn't answer?

On Edesy, ring-no-answer moves the call to the next agent the strategy picks. The caller stays in the queue with music on hold while that happens.

### Does skill-based routing cost extra on Edesy?

Skill routing is part of the Professional plan, Rs 2,500 per agent per month (up to 100 agents), and Enterprise. Starter is Rs 1,500 per agent per month. Call minutes are extra at the voice rate, and prices exclude 18% GST.

### What happens if no agent with the required skill is free?

On Edesy, skill-based routing falls back to any available agent, picked by longest idle, so the caller isn't held waiting for one specific person. If you need strict skill-only routing, keep enough agents in each skill.