Apollo has quietly become the default B2B data provider for startups and mid-market teams. Per their site, they have 270M+ contacts, and the data quality has gotten genuinely good over the past year.

What makes Apollo special is that it's not just a database. It's a database plus sequencing plus analytics in one platform. You can go from finding a prospect to enrolling them in a sequence without switching tabs.

Want to see how it stacks up head-to-head? Check out our Apollo vs ZoomInfo comparison and Apollo alternatives.

Dive deeper into the Apollo profile on our directory page.

ZoomInfo is the 800-pound gorilla of B2B data. Per their site, they maintain 260M+ professional profiles, and their data accuracy is consistently rated among the highest in the industry according to G2 reviews.

The catch? It's expensive. We're talking $15K-25K/year for most enterprise contracts. And that's before you add on the intent data, website visitor tracking, and all the other modules they'll try to upsell you on.

But if you're an enterprise sales org that needs rock-solid data with deep firmographic and technographic detail, ZoomInfo is still the benchmark everyone else is measured against.

Explore ZoomInfo alternatives if the price tag is too steep, or see our full ZoomInfo directory listing.

Clay is different from everything else on this list. Instead of being a single database, Clay aggregates data from 100+ sources (per their site) and lets you build enrichment waterfalls. If one provider doesn't have the email, it checks the next one, then the next one.

This approach is incredibly powerful. You're not locked into one provider's data quality. You can layer ZoomInfo data with Apollo data with Clearbit data and pick the best result for each prospect.

See how Clay compares directly in our Clay vs ZoomInfo breakdown. Full details on our Clay directory page.

If you're selling into Europe, Cognism should be at the top of your list. They've built their entire platform around GDPR compliance, and their European contact data is notably better than most US-first providers.

They also have strong phone-verified mobile numbers, which is a big deal if your team does cold calling. Per their positioning, they maintain one of the largest databases of verified European B2B contacts.

Read our Cognism vs Apollo comparison to see which fits your geo better. More details on the Cognism directory page.

Lusha keeps things simple. Their Chrome extension lets you pull contact details while browsing LinkedIn or company websites. No complicated setup, no waterfall workflows. Just fast, clean lookups.

The free tier gives you a handful of credits per month, which is enough to test the data quality. Their paid plans start at $49/mo per their site.

Check out our Lusha directory listing for the full breakdown.

Seamless.AI takes a different approach. Instead of maintaining a static database, it uses AI to search the web in real-time and find contact information. Per their positioning, this means the data is always current because it's being pulled fresh.

The trade-off is that lookups can be slower, and the results can be inconsistent depending on how much information is publicly available about a given prospect.

Lead411 has been around for a while, and they've carved out a solid niche with intent data and sales triggers. Per their marketing, they maintain 450M+ contacts with verified emails and direct dials.

What sets them apart is their focus on sales triggers like funding events, hiring surges, and new executive appointments. This helps you reach out at the right moment, not just to the right person.

UpLead markets themselves on accuracy, and they back it up. Per their site, they offer a 95% data accuracy guarantee, meaning you get credits back for any bounced emails. That's a bold promise most competitors won't make.

The database is smaller than ZoomInfo or Apollo, but what's there tends to be clean and reliable.

Clearbit was acquired by HubSpot and rebranded as Breeze Intelligence. If you're already on HubSpot, this is essentially free enrichment baked into your CRM. It auto-enriches contacts and companies with firmographic data.

As a standalone product, it's less compelling. But as part of the HubSpot ecosystem, it's a no-brainer.

RocketReach offers a solid database at a lower price point than most competitors. Per their site, plans start around $39/mo, making it one of the most accessible options for individual reps and bootstrapped teams.

The data quality is decent for basic email and phone lookups, though it doesn't have the depth of firmographic data you'd get from ZoomInfo or Apollo.

Kaspr is a LinkedIn-focused data provider that's popular in Europe. Their Chrome extension pulls contact data directly from LinkedIn profiles, and they offer a free tier to get started.

Demandbase isn't really a traditional contact data provider. It's more of an account-based marketing platform with strong intent data capabilities. Per their positioning, they excel at identifying which accounts are actively researching solutions in your category.

If you're running ABM plays and need to know which accounts to prioritize, Demandbase is excellent. For individual contact lookups, look elsewhere.

B2B Data Providers Comparison Table

How to Choose the Right B2B Data Provider

Don't just pick the one with the biggest database. Here's a practical framework:

Step 1: Define your geographic focus. Selling mostly in Europe? Cognism wins. North America? Apollo or ZoomInfo. Global? Consider Clay's multi-source approach.

Step 2: Match your budget to your team size. Solo rep on a budget? RocketReach or Apollo's free tier. Mid-market team? Apollo or Lusha paid. Enterprise with budget? ZoomInfo or Demandbase.

Step 3: Consider your workflow. If you want everything in one place (data + sequences + analytics), Apollo is hard to beat. If you want to build custom enrichment workflows, Clay is the answer. If you just need quick lookups, Lusha or Kaspr.

Step 4: Test before you commit. Most providers offer free trials or free tiers. Run 100 contacts through each one and check the bounce rate yourself. Real-world accuracy matters more than marketing claims.

Step 5: Think about data freshness. Static databases decay at roughly 30% per year (people change jobs, companies rebrand). Providers with real-time verification or regular refresh cycles will save you headaches.

Use our free ICP Builder skill to clarify exactly who you're targeting before choosing a provider. And try the Prospect Research skill to see what data you can gather right now.

For a deeper look at tools that enrich and clean your existing data, read our guide on the best data enrichment tools for 2026.

Free AI Skills to Supercharge Your Data

Before you spend a dollar on data, try these free AI-powered skills on our site:

• Prospect Research - Deep-dive any prospect using public data sources
• ICP Builder - Define your ideal customer profile so you know exactly what data to buy
• Tech Stack Analyzer - Discover what technology your prospects are using
• Competitor Intel - Research how competitors position against you
• Trigger Event Finder - Identify buying signals and timing triggers for outreach

These pair perfectly with any B2B data provider. Use them to qualify prospects before burning credits on lookups.

Frequently Asked Questions

What is a B2B data provider?

A B2B data provider is a platform that sells or gives access to business contact information like emails, phone numbers, job titles, company details, and firmographic data. Sales and marketing teams use them to find and reach potential customers. For a broader overview of tools in this space, see our sales intelligence guide.

Which B2B data provider has the most accurate data?

It depends on your target market and segment. ZoomInfo and Cognism consistently rate highest for accuracy according to G2 reviews. UpLead is the only provider offering a 95% accuracy guarantee with credit-backs for bounces. In practice, using Clay to waterfall multiple providers often yields the best overall accuracy.

Can I use multiple B2B data providers at once?

Absolutely, and you probably should. Tools like Clay are built specifically for this. You set up an enrichment waterfall that checks Provider A first, then Provider B if A doesn't have the data. This approach dramatically improves coverage and accuracy. See our Clay vs ZoomInfo comparison for more on this strategy.

What's the best free B2B data provider?

Apollo.io has the most generous free tier with limited monthly credits and access to their full database. Lusha and Kaspr also offer free plans, though with fewer credits. If you're on HubSpot, Clearbit/Breeze gives you basic enrichment at no extra cost.

How much does B2B data cost?

The range is massive. You can start for free with Apollo or Lusha, pay $39-99/mo for tools like RocketReach or UpLead, or invest $15K-30K+/year for enterprise platforms like ZoomInfo or Demandbase. Your budget should match your team size and outbound volume.

How do I evaluate B2B data quality before buying?

Run a test batch. Take 100 contacts from your target market and check email validity (use a verification tool), phone accuracy (call a sample), and title/company freshness. Compare results across 2-3 providers before committing to an annual contract. Our Revenue Finder tool can help you identify which providers are strongest for your specific ICP.

Also check out our guides on market intelligence software and competitive intelligence tools if you need broader research capabilities beyond just contact data.