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Side-by-side comparison · Sales & Customer Support

Freshdesk vs Retell AI vs Sierra

Everything that matters when choosing between them, in one place: our rating, what each can do, what they cost, and the trade-offs.

Freshdesk

3.8

From $19/agent/mo

Best overall

Retell AI

4.1

From About $0.07–$0.31/min

Sierra

3.9

Free to start

Comparing 3 tools, the maximum.

At a glance

Easiest to use

Pick it if: Small and mid-size businesses that handle customer questions by email, chat and phone and need a proper ticket system.

Best overallBest value

Pick it if: Service businesses and agencies that want an AI receptionist or phone agent without hiring developers.

Pick it if: Large consumer brands that want an AI agent to handle a big share of their customer conversations end to end.

Overview

AttributeFreshdeskRetell AISierra
In one lineHelpdesk for email, chat and phone support, with Freddy AI to answer and assist.AI phone agents that answer calls, book appointments and make outbound calls.Builds and runs AI customer service agents for big brands, across chat, email and phone.
Pricing modelPaidPaidPaid
Starting price$19/agent/moAbout $0.07–$0.31/minSee website
Free plan No No No
Works with Claude Code Yes Yes No

Rating breakdown

Our scores out of 5. The higher bar in each row is highlighted.

AttributeFreshdeskRetell AISierra
Overall rating3.84.1Winner3.9
Ease of useHow quickly someone non-technical gets value from it.
4.0
3.5
3.0
FeaturesHow completely it covers its own job, and how well the pieces fit together.
4.0
4.5
4.5
Output qualityHow good the results are before you fix them.
3.5
4.5
4.5
Value for moneyWhat you get for the price, including the free plan.
3.5
4.0
3.0
Speed & reliabilityHow fast it is and how often it falls over.
4.0
4.0
4.5

Feature comparison

A tick means it does this today. A dash means we haven't checked.

AttributeFreshdeskRetell AISierra
Access & platform
Free plan No No No
Mobile app Yes––
Desktop app No––
Browser extension–––
API access Yes Yes–
Teams & business
Team workspace Yes Yes Yes
Enterprise plan or SSO Yes Yes Yes
Connects to other apps Yes Yes Yes
Open source or self-hosted No No No
AI abilities
Works with your files Yes Yes Yes
Understands images–––
Makes images No No No
Makes video No No No
Writes code No––
Runs agents or automations Yes Yes Yes
Learns your brand or style–– Yes
Works in many languages Yes Yes Yes
Capabilities score8/ 177/ 177/ 17

Pricing

Plans as listed on each vendor's site when we last checked. Confirm before you buy.

AttributeFreshdeskRetell AISierra
Plans

Growth

$19/agent/mo billed yearly

Small teams moving off a shared inbox.

Pay as you goOur pick

About $0.07–$0.31/min

Most small businesses and agencies.

EnterpriseOur pick

Custom

Large companies with high conversation volumes.

ProOur pick

$55/agent/mo billed yearly

Growing teams that need routing and deadlines.

Enterprise

Custom

High call volumes and compliance needs.

Enterprise

$89/agent/mo billed yearly

Larger support teams with admin and security needs.

Which plan to pickGrowth is fine for a few agents answering email. Most growing teams end up on Pro for routing, SLAs and the option to add Copilot. Budget for extra AI Agent sessions once the first 500 are used.Start on pay as you go with the free credits, build one agent for your most common call and test it on your own phone. Talk to sales only once you run thousands of minutes a month.There is one route: talk to Sierra's sales team. Agree clearly what counts as an outcome you pay for, and what setup and services cost, before you sign.

Key features

AttributeFreshdeskRetell AISierra
Standout features
  • Ticketing and shared inbox
  • Freddy AI Agent
  • Freddy AI Copilot
  • Help centre and portal
  • Automations and SLAs
  • Reports
  • Phone agents
  • Flow builder
  • Appointment booking
  • Knowledge base
  • Batch calling
  • Call analysis
  • Agent Studio
  • Ghostwriter
  • One agent, every channel
  • Connected to your systems
  • Insights and testing

Pros and cons

AttributeFreshdeskRetell AISierra
Pros
  • Cheaper and quicker to set up than Zendesk
  • Clean, easy agent inbox that new staff pick up fast
  • Large marketplace of apps and integrations
  • AI agent included to start, without a separate contract
  • Public API for custom workflows
  • Natural voices and quick responses
  • Visual builder makes it usable for non-developers
  • Pay per minute with no platform fee
  • Strong reviews from small businesses and agencies
  • Agents take real actions, not just answer questions
  • Covers voice as well as chat, SMS, WhatsApp and email
  • Outcome-based pricing means you pay for results, not seats
  • Proven at very large brands
Cons
  • 2026 price rise, and the free plan is now only a six-month program for one or two agents
  • Useful features like custom dashboards and smart routing are locked to Pro and above
  • Freddy AI costs add up: sessions billed in packs and Copilot priced per agent
  • AI agent needs tuning and handles multi-step conversations less well than Intercom
  • Mixed reviews of Freshworks support and billing when issues arise
  • Per-minute cost varies a lot with your model and voice choices
  • Takes testing to handle real callers reliably
  • Some users want more voice and customisation options
  • No public pricing; estimates put it out of reach for most small and mid-sized businesses
  • No trial or self-serve option, so you are committing to a sales process and a project
  • Few independent reviews to check claims against
  • You depend on Sierra's team for much of the build

Who each one is for

AttributeFreshdeskRetell AISierra
Best for
  • Turning a support inbox into tracked tickets
  • Building a help centre and customer portal
  • Deflecting repeat questions with an AI agent
  • Teams of 3 to 100 support agents
  • AI receptionist for a small business
  • Booking appointments by phone
  • Answering after-hours and overflow calls
  • Outbound reminder and follow-up calls
  • High-volume customer service at large brands
  • AI phone agents that take real actions
  • Returns, bookings and account changes
  • Saving cancellations and handling retention calls
You'll find it used by
  • Customer support teams
  • E-commerce stores
  • SaaS companies
  • IT and service desks
  • Small business owners
  • Clinics
  • Voice AI agencies
  • Customer service teams
  • Developers
  • Enterprise support teams
  • Contact centres
  • Retail brands
  • Banks and insurers
  • Telcos

Questions people ask

Which is better, Freshdesk, Retell AI or Sierra?

Retell AI scores highest overall in our ratings (Freshdesk 3.8/5, Retell AI 4.1/5 and Sierra 3.9/5). Freshdesk is best for turning a support inbox into tracked tickets and building a help centre and customer portal. Retell AI is best for AI receptionist for a small business and booking appointments by phone. Sierra is best for high-volume customer service at large brands and AI phone agents that take real actions.

Which is cheaper, Freshdesk, Retell AI or Sierra?

Freshdesk: There's no free plan. Paid plans start at $19/agent/mo. Retell AI: There's no free plan. Paid plans start at About $0.07–$0.31/min. Sierra: Pricing isn't published; check the vendor's site for a quote.

Which is easier to use, Freshdesk, Retell AI or Sierra?

Freshdesk rates highest for ease of use in our scores. Small and mid-size businesses that handle customer questions by email, chat and phone and need a proper ticket system.

How we compare

Ratings are our own, from using each tool, across ease of use, features, output quality, value for money, speed & reliability.

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