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Side-by-side comparison · Sales & Customer Support

Hiver vs Reply.io 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.

Hiver

3.9

From $25/user/mo

Reply.io

3.7

From From $49/user/mo

Sierra

3.9

Free to start

Comparing 3 tools, the maximum.

At a glance

Best valueEasiest to use

Pick it if: Small and mid-sized teams who answer customers or suppliers from a shared Gmail address and want structure without leaving Gmail.

Pick it if: Small sales teams, founders and agencies running cold email and LinkedIn outreach.

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

Overview

AttributeHiverReply.ioSierra
In one lineShared inbox and helpdesk that runs inside Gmail, with AI that drafts and answers replies.Cold email and LinkedIn outreach sequences, plus an AI SDR that writes and replies.Builds and runs AI customer service agents for big brands, across chat, email and phone.
Pricing modelPaidPaidPaid
Starting price$25/user/moFrom $49/user/moSee 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.

AttributeHiverReply.ioSierra
Overall rating3.93.73.9
Ease of useHow quickly someone non-technical gets value from it.
4.5
4.0
3.0
FeaturesHow completely it covers its own job, and how well the pieces fit together.
4.0
4.0
4.5
Output qualityHow good the results are before you fix them.
3.5
3.5
4.5
Value for moneyWhat you get for the price, including the free plan.
4.0
3.5
3.0
Speed & reliabilityHow fast it is and how often it falls over.
3.5
3.5
4.5

Feature comparison

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

AttributeHiverReply.ioSierra
Access & platform
Free plan No No No
Mobile app Yes––
Desktop app–––
Browser extension Yes Yes–
API access Yes Yes–
Teams & business
Team workspace Yes Yes Yes
Enterprise plan or SSO Yes– Yes
Connects to other apps Yes Yes Yes
Open source or self-hosted No No No
AI abilities
Works with your files–– 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
Capabilities score7/ 176/ 177/ 17

Pricing

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

AttributeHiverReply.ioSierra
Plans

Growth

$25/user/mo billed yearly, or $35 monthly

Small teams running one or two shared inboxes.

Email Volume

From $49/user/mo billed yearly, or $59 monthly

Email-only cold outreach.

EnterpriseOur pick

Custom

Large companies with high conversation volumes.

ProOur pick

$55/user/mo billed yearly, or $65 monthly

Support teams that need targets and connected tools.

MultichannelOur pick

$89/user/mo billed yearly, or $99 monthly

Teams running email and LinkedIn together.

Elite

$85/user/mo billed yearly, or $95 monthly

Larger teams wanting AI quality checks and tighter security.

Jason AI SDR

From $500/mo billed yearly

Teams wanting AI to run outbound end to end.

Which plan to pickGrowth is enough for a small team that just needs a tidy shared inbox with AI help. Choose Pro if you need response-time targets, CRM or Shopify data next to each email, or the API. Voice is an add-on at $30 per seat.Multichannel is the best value if you use LinkedIn at all, since the add-ons on Email Volume quickly cost more. Only look at Jason AI SDR once your manual sequences are already booking meetings.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

AttributeHiverReply.ioSierra
Standout features
  • Shared inbox in Gmail
  • AI agents
  • AI copilot
  • Collaboration
  • Hiver Omni
  • Multichannel sequences
  • Deliverability tools
  • Jason AI SDR
  • AI email writer
  • Contact data
  • Agency features
  • Agent Studio
  • Ghostwriter
  • One agent, every channel
  • Connected to your systems
  • Insights and testing

Pros and cons

AttributeHiverReply.ioSierra
Pros
  • Almost no training: the team keeps working in Gmail
  • AI agents and copilot included from the cheapest plan
  • Good for non-support teams like finance and HR
  • Cheaper than Zendesk or Intercom for small teams
  • 24/7 support on every plan
  • Email, LinkedIn, calls and SMS in one sequence
  • Warm-up and deliverability tools included
  • Fair price for small teams and agencies
  • AI SDR option when you want less hands-on work
  • 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
  • Gmail add-on can be slow, lose connection or log users out
  • Search and formatting are weaker than in a full helpdesk
  • Key integrations and the API only start on Pro
  • Seats sold in blocks, with a two-seat minimum
  • Frequent complaints about auto-renewals, minimum terms and refunds
  • LinkedIn and calls are paid add-ons on the cheaper plan
  • AI SDR is a big price jump and still needs supervising
  • Some users report bugs and emails sent in error
  • 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

AttributeHiverReply.ioSierra
Best for
  • Running support@ or info@ as a team
  • Assigning and tracking customer emails
  • Finance and HR shared mailboxes
  • AI-drafted email replies
  • Teams that want to stay in Gmail
  • Cold email campaigns
  • Email plus LinkedIn sequences
  • Agencies running outreach for clients
  • Handing outbound to an AI SDR
  • 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
  • Finance and accounts teams
  • Operations teams
  • Logistics companies
  • Agencies
  • Founders
  • Sales development reps
  • Lead generation agencies
  • Recruiters
  • Enterprise support teams
  • Contact centres
  • Retail brands
  • Banks and insurers
  • Telcos

Questions people ask

Which is better, Hiver, Reply.io or Sierra?

They tie on our overall rating (Hiver 3.9/5, Reply.io 3.7/5 and Sierra 3.9/5). Hiver is best for running support@ or info@ as a team and assigning and tracking customer emails. Reply.io is best for cold email campaigns and email plus LinkedIn sequences. Sierra is best for high-volume customer service at large brands and AI phone agents that take real actions.

Which is cheaper, Hiver, Reply.io or Sierra?

Hiver: There's no free plan. Paid plans start at $25/user/mo. Reply.io: There's no free plan. Paid plans start at From $49/user/mo. Sierra: Pricing isn't published; check the vendor's site for a quote.

Which is easier to use, Hiver, Reply.io or Sierra?

Hiver rates highest for ease of use in our scores. Small and mid-sized teams who answer customers or suppliers from a shared Gmail address and want structure without leaving Gmail.

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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