Side-by-side comparison · Sales & Customer Support
Apollo.io vs Clay 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.
Comparing 3 tools, the maximum.
At a glance
Pick it if: Founders, small sales teams and marketers who need to find B2B contacts and email them.
Pick it if: Growth marketers, sales ops people and agencies who build targeted lead lists and personalised outbound.
Pick it if: Large consumer brands that want an AI agent to handle a big share of their customer conversations end to end.
Overview
| Attribute | Apollo.io | Clay | Sierra |
|---|---|---|---|
| In one line | B2B contact database with emails and phone numbers, plus sequences to reach them. | Builds and enriches lead lists from 100+ data sources, with an AI agent for web research. | Builds and runs AI customer service agents for big brands, across chat, email and phone. |
| Pricing model | Freemium | Freemium | Paid |
| Starting price | $49/seat/mo | From $167/mo | See website |
| Free plan | Yes | Yes | No |
| Works with Claude Code | Yes | No | No |
Rating breakdown
Our scores out of 5. The higher bar in each row is highlighted.
| Attribute | Apollo.io | Clay | Sierra |
|---|---|---|---|
| Overall rating | 4.0Winner | 3.7 | 3.9 |
| Ease of useHow quickly someone non-technical gets value from it. | 4.5 | 2.5 | 3.0 |
| FeaturesHow completely it covers its own job, and how well the pieces fit together. | 4.5 | 5.0 | 4.5 |
| Output qualityHow good the results are before you fix them. | 3.0 | 4.5 | 4.5 |
| Value for moneyWhat you get for the price, including the free plan. | 4.0 | 3.0 | 3.0 |
| Speed & reliabilityHow fast it is and how often it falls over. | 4.0 | 3.5 | 4.5 |
Feature comparison
A tick means it does this today. A dash means we haven't checked.
| Attribute | Apollo.io | Clay | Sierra |
|---|---|---|---|
| Access & platform | |||
| Free plan | Yes | Yes | 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 | Yes |
| Connects to other apps | Yes | Yes | Yes |
| Open source or self-hosted | No | No | No |
| AI abilities | |||
| Works with your files | – | Yes | Yes |
| Understands images | – | – | – |
| Makes images | No | No | No |
| Makes video | No | No | No |
| Writes code | – | – | – |
| Runs agents or automations | Yes | Yes | Yes |
| Learns your brand or style | – | – | Yes |
| Works in many languages | – | – | Yes |
| Capabilities score | 8/ 17 | 8/ 17 | 7/ 17 |
Pricing
Plans as listed on each vendor's site when we last checked. Confirm before you buy.
| Attribute | Apollo.io | Clay | Sierra |
|---|---|---|---|
| Plans | Free Free Founders testing outbound. | Free Free Learning Clay and small tests. | EnterpriseOur pick Custom Large companies with high conversation volumes. |
Basic $49/seat/mo billed yearly Individual sellers doing regular outbound. | LaunchOur pick From $167/mo, less billed yearly Founders and small teams building outbound lists. | ||
ProfessionalOur pick $79/seat/mo billed yearly Full-time reps. | Growth From $446/mo, less billed yearly Teams syncing Clay with their CRM. | ||
Organization $119/seat/mo billed yearly (min 3 seats) Sales teams wanting advanced controls. | Enterprise Custom Large teams needing SSO and controls. | ||
| Which plan to pick | Start on Free to check the data covers your market. Basic suits one person prospecting; Professional is worth it if you also call prospects or want AI scoring. Monthly billing costs noticeably more than the yearly prices shown. | Learn on Free, then move to Launch when you are ready to run real campaigns. Only take Growth if you need CRM sync or the API. Set credit budgets on every table. | 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
| Attribute | Apollo.io | Clay | Sierra |
|---|---|---|---|
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Pros and cons
| Attribute | Apollo.io | Clay | Sierra |
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Who each one is for
| Attribute | Apollo.io | Clay | Sierra |
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Questions people ask
Which is better, Apollo.io, Clay or Sierra?
Apollo.io scores highest overall in our ratings (Apollo.io 4.0/5, Clay 3.7/5 and Sierra 3.9/5). Apollo.io is best for finding business emails and phone numbers and Building B2B lead lists. Clay is best for building niche lead lists and finding emails and phone numbers from many sources. Sierra is best for high-volume customer service at large brands and AI phone agents that take real actions.
Which is cheaper, Apollo.io, Clay or Sierra?
Apollo.io: There's a free plan, and paid plans start at $49/seat/mo. Clay: There's a free plan, and paid plans start at From $167/mo. Sierra: Pricing isn't published; check the vendor's site for a quote.
Which is easier to use, Apollo.io, Clay or Sierra?
Apollo.io rates highest for ease of use in our scores. Founders, small sales teams and marketers who need to find B2B contacts and email them.
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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