B2B Lead Generation Outsourcing: 15 Tools & Practical Advice
Explore whether B2B lead generation outsourcing is right for your business. Compare top AI lead generation tools and agencies, including 11x.
For most B2B companies and GTM teams, maintaining a healthy sales pipeline is harder than it used to be. Buying cycles are longer, inboxes are crowded, and it takes more effort to connect with decision-makers. Even experienced sales teams are exploring outsourcing lead generation to maintain consistent outreach and qualified leads.
According to Forrester, B2B companies with mature outbound processes achieve 30% higher conversion rates than those relying only on inbound marketing campaigns. Gartner adds that outsourcing can lower customer acquisition costs by 18 to 25 percent.
This guide explains why companies outsource lead generation, what trade-offs to expect, and how 15 leading tools and lead generation agencies, including 11x, the all-in-one AI GTM platform, which helps sales teams scale outreach and qualification with speed and accuracy.
Why Companies Outsource Lead Generation
Outsourcing lead generation has evolved from a simple cost decision into a performance strategy. GTM leaders use it to increase speed, maintain flexibility, and free their in-house teams to focus on closing deals.
Here’s why the model works:
- Speed and accuracy. Experienced lead generation agencies already know how to identify decision-makers, craft compliant messaging, and run personalized email outreach sequences.
- Scalable pipeline. Outsourcing allows sales teams to expand or reduce outreach volume without recruiting or training additional SDRs.
- SEO and visibility. Some providers pair content marketing with B2B lead generation services, improving organic inbound flow while outbound runs in parallel.
- Data-driven follow-up. Automated workflows trigger timely, relevant follow-ups that convert potential customers into qualified leads.
- Strategic partnership. The best lead generation agencies don’t just execute. They help set KPIs, refine marketing strategies, and improve optimization across the sales process.
For growth-focused GTM leaders, outsourcing provides a measurable performance multiplier, blending human expertise, AI automation, and scalability.
Pros and Cons of Outsourcing Lead Generation
Every sales process involves trade-offs. Knowing them upfront helps companies balance internal control with external leverage.
Common challenges are:
- Brand alignment. If a lead generation company misreads your target audience or tone, messaging can feel off-brand, which is especially risky for companies in regulated industries like healthcare or finance.
- Lead quality. Poorly verified data reduces conversion rates and creates friction in your CRM.
- Sales cycle fit. Not all B2B lead generation agencies are suited for long enterprise sales cycles.
- Integration issues. Without proper CRM sync, real-time insights and metrics can be lost.
- Internal collaboration. Your in-house team must stay involved for the best results. The most effective partnerships treat external agencies as part of the same sales team.
Handled strategically, outsourcing lead generation extends your capacity, ensuring a steady stream of high-quality leads while maintaining brand control.
From Agencies to AI SDRs: How Outsourcing Has Changed
Traditionally, outsourcing meant hiring a lead generation agency to run outbound or manage SDRs. That model still exists, but now coexists with a new one — AI SDRs.
An AI SDR is an autonomous sales agent that uses artificial intelligence to handle outbound and inbound prospecting from start to finish. It analyzes CRM and market data to identify high-intent leads, writes and sends personalized outreach across channels like email, and automatically manages follow-ups.
The core benefits that make AI SDRs important for modern sales teams include:
- Smarter deliverability with optimized send times and strong sender reputation management
- Intelligent lead targeting and qualification that uses behavioral and buying signal data
- Scalable outreach without increasing SDR headcount
- Always-on coverage across time zones and markets, so no lead slips through the cracks
- Better visibility with real-time reporting and pipeline forecasting
Unlike basic sales automation tools, AI SDRs can research prospects, identify pain points, pick up on buying signals, and adapt their messaging based on how leads engage. They act like true digital sales development reps—consistent, data-driven, and always learning.
The 15 Best B2B Lead Generation Service Providers
Below are 15 lead generation tools and companies grouped by three categories to reflect how the market now operates, including AI-led B2B lead generation platforms, data and enrichment service providers, and human-led lead generation agencies.
Here is a quick summary table:
AI-Led B2B Lead Generation Platforms
AI-led lead generation platforms act as autonomous SDRs that handle prospecting, scoring, and email outreach, replacing repetitive work with continuous automation.
1. 11x
11x Alice is an AI SDR that autonomously manages B2B lead generation, outreach, and lead qualification. She identifies potential leads from a database of over 400 million verified B2B contacts, writes personalized messages based on key buying signals, and sends them automatically across email.
Features:
- Unified data intelligence combining 21+ premium data providers, real-time signals, and live search for sharper lead targeting and timing.
- Predictive AI lead scoring to identify and prioritize qualified prospects.
- Advanced research agents and personalization waterfalls that adapt messaging by role, product, and market, and scale with your needs.
- AI-driven email warming, inbox rotation, and spam protection to ensure deliverability, even at high volumes.
- Enterprise-grade compliance and support, including SOC 2, GDPR, and CASA Tier 3 certifications, plus dedicated CSMs and Slack support to get started from day 1.
Strengths: Scalable, data-driven, and always-on outreach execution. 11x acts as an all-in-one GTM platform, replacing multiple point solutions for enrichment, deliverability, and outreach.
Best Fit: Ideal for SaaS and enterprise GTM leaders looking to build repeatable, scalable lead generation processes.
ROI Impact: Gupshup saw a 50 % increase in SQLs per SDR after adopting Alice, enabling a 1.5× boost in output per rep—and freeing up time for strategic initiatives like calling and rapid campaign testing, all without increasing headcount.
2. Apollo.io
Apollo.io combines B2B lead generation data with sequencing tools for automated outreach. It acts as a lightweight AI SDR for smaller sales teams.
Features:
- Database of 250M+ B2B leads generated globally.
- Built-in email campaigns, cold calling, and CRM sync.
- Automation to streamline sequences and send-time optimization.
- Metrics dashboards for analyzing conversion rates.
Strengths: Affordable, user-friendly, and ideal for startups refining their lead gen marketing strategies.
Weaknesses: Some industry data is inconsistent.
Best fit: Small sales teams building scalable B2B lead generation services.
3. DemandScience
DemandScience uses AI and predictive data to prioritize high-intent B2B leads generated for global B2B marketing programs.
Features:
- Predictive lead scoring and behavioral insights for qualified leads.
- Data-driven audience segmentation based on content consumption.
- Global marketing campaign integration for multi-channel outreach.
- Ongoing optimization through engagement metrics.
Strengths: Deep insights for B2B sales programs.
Weaknesses: Best for longer sales cycles.
Best fit: Enterprise marketers managing ABM and content marketing workflows.
4. CIENCE
CIENCE blends human SDRs with AI automation to run outbound lead generation efficiently.
Features:
- AI-based prospect identification and scoring for qualified leads.
- Multi-channel outreach using email and cold calling.
- Detailed reporting for real-time optimization.
- Data research and CRM enrichment for sales pipelines.
Strengths: Strong analytics and data-driven execution.
Weaknesses: Setup complexity for small teams.
Best fit: Service providers and lead generation agencies that want measurable B2B lead generation results.
Data and Enrichment Service Providers
Data tools fuel every B2B lead generation strategy. They give teams access to verified contacts, target audience insights, and behavioral intent signals that power smarter outreach and lead gen.
5. Kaspr
Kaspr captures verified contact data, helping sales teams reach potential customers faster.
Features:
- Chrome extension for instant lead gen data capture.
- Email and phone verification for high-quality leads.
- GDPR-compliant enrichment.
- Direct CRM export and real-time data sync.
Strengths: Reliable B2B lead generation data and fast setup.
Weaknesses: Focused mainly on data collection, not full outreach campaigns.
Best fit: Sales teams and startups doing self-managed B2B lead generation.
6. Cognism
Cognism provides GDPR-compliant B2B lead generation services enriched with intent data and qualified leads globally.
Features:
- Verified sales leads with real-time updates.
- Buyer intent signals and advanced filtering by target markets.
- CRM enrichment and data-driven optimization.
- Metrics tracking for sales pipeline health.
Strengths: Excellent compliance and data quality.
Weaknesses: Requires process discipline for best results.
Best fit: B2B companies in healthcare, finance, or regulated sectors.
7. LeadIQ
LeadIQ helps sales teams collect and enrich verified sales leads and sync them automatically to their CRM. It’s a popular choice for teams focused on fast, accurate prospecting.
Features:
- One-click lead gen data capture and real-time enrichment.
- CRM integrations with Salesforce, HubSpot, and Outreach.
- Multi-channel tagging and collaboration tools for team-based outreach.
- Automatic follow-up reminders for uncontacted potential customers.
Strengths: Speeds up lead generation processes and keeps contact data clean.
Weaknesses: Limited sequencing or email marketing automation.
Best fit: In-house teams building efficient, data-first B2B lead generation strategies.
8. UpLead
UpLead delivers verified firmographic data for B2B sales professionals and lead generation agencies.
Features:
- Real-time lead verification and company-level filters.
- CRM integration and API for seamless automation.
- Optimization tools to improve the lead generation process accuracy.
- Pricing flexibility for startups and growing B2B companies.
Strengths: Highly accurate data and a user-friendly interface.
Weaknesses: Minimal email outreach capabilities.
Best fit: SMBs and lead generation companies enriching their databases.
9. ZoomInfo
ZoomInfo remains the enterprise standard for B2B lead generation and B2B marketing data intelligence.
Features:
- Global B2B lead generation database with verified decision-makers.
- Intent signals that reveal active target markets.
- CRM and marketing campaign automation for optimization at scale.
- Detailed metrics and data-driven insights for sales pipeline forecasting.
Strengths: Deep coverage and advanced analytics.
Weaknesses: High pricing and complex setup for smaller firms.
Best fit: Enterprises and RevOps leaders managing complex sales processes.
Human-Led Lead Generation Agencies
These lead generation agencies offer personalized outreach driven by human SDRs. They remain valuable for companies seeking creative, relationship-based marketing strategies with tailored messaging.
10. RevBoss
RevBoss blends experienced SDRs with proprietary tools to execute outbound lead generation campaigns for B2B companies.
Features:
- End-to-end lead generation process design, email outreach, and appointment setting.
- Data-driven list creation and multi-channel follow-ups.
- Performance dashboards with key metrics for optimization.
- Regular review meetings to align on KPIs and partnership results.
Strengths: High customization and transparent sales process tracking.
Weaknesses: Longer onboarding and higher pricing.
Best fit: SaaS firms and B2B companies seeking a predictable, qualified pipeline.
11. SalesBread
SalesBread runs 1:1 personalized email outreach campaigns designed to reach potential clients with human nuance.
Features:
- Customized messaging per target audience and industry.
- Manual follow-ups for quality leads and conversation nurturing.
- A/B testing for tone and optimization.
- Case studies shared with clients for continual learning.
Strengths: Exceptional response rates and warm sales leads.
Weaknesses: Less scalable than AI-based B2B lead generation services.
Best fit: Startups and founders who prioritize personal outreach.
12. Belkins
Belkins delivers complete lead generation services with a focus on appointment setting and lead nurturing.
Features:
- Full-cycle B2B lead generation marketing campaigns.
- Multi-channel engagement via email marketing, cold calling.
- Continuous optimization for higher conversion rates.
- Dedicated campaign managers ensuring consistent, qualified leads.
Strengths: Excellent for repeatable lead generation processes and steady sales pipeline growth.
Weaknesses: Tiered pricing with limited flexibility for smaller clients.
Best fit: B2B companies with established sales teams needing consistent high-quality leads.
13. Martal Group
Martal Group provides dedicated SDRs and AEs to act as your embedded in-house team for outbound lead generation.
Features:
- Personalized messaging and cadence planning.
- CRM sync for real-time visibility.
- Appointment setting and post-call follow-ups.
- Campaign-level optimization through data tracking.
Strengths: Transparent process and bilingual team.
Weaknesses: Regional focus mainly on North America.
Best fit: SaaS and tech startups expanding into U.S. and Canadian target markets.
14. OutboundView
OutboundView operates as a consulting service provider, helping sales teams improve internal lead generation strategies.
Features:
- Custom outbound methodologies and playbook development.
- Sales process audits and enablement training.
- Optimization workshops for sales teams, improving outreach quality.
- Frameworks for long-term revenue growth and internal alignment.
Strengths: Process expertise and data-driven advisory model.
Weaknesses: No direct campaign execution.
Best fit: In-house teams restructuring for scalable B2B lead generation.
15. Callbox
Callbox is a global lead generation company offering multi-channel B2B lead generation services and appointment setting.
Features:
- Integrated email marketing, cold calling, and social media outreach.
- Proprietary global contact database for potential customers.
- Localized messaging and follow-up processes by region.
- CRM integration and real-time analytics for sales teams.
Strengths: Strong regional coverage and multilingual support.
Weaknesses: Higher pricing and longer campaign setup time.
Best fit: B2B companies targeting multiple target markets through outsourced sales.
How 11x Fits In
Modern lead generation outsourcing isn't about cost-cutting—it's about building a scalable system that adapts to your growth stage and sales cycle.
The future of outbound is hybrid. AI handles repetitive tasks like data enrichment, multi-touch sequences, and meeting scheduling, while your team focuses on strategy, relationships, and closing deals. Whether you choose an agency, a platform, or a combination, the goal remains the same: predictable pipeline growth without sacrificing quality or burning out your team.
By combining AI automation with human insight, 11x builds an engine that runs continuously, giving sales teams an always-on pipeline that scales with your business.
Ready to scale outbound with AI? Get started with 11x and see how AI SDR Alice transforms lead generation into a continuous growth engine.
Frequently Asked Questions
Yes, when executed properly. Gartner reports that companies using AI-assisted lead generation see up to 22% higher productivity. The real benefit is focus and specialization. Your sales team spends time on discovery calls and deal negotiation instead of list building and cold outreach.
Outsourcing works best when you have a clear ideal customer profile, defined success metrics, and bandwidth to work with qualified leads.
Start by identifying your specific gap: volume, lead quality, or conversion rates.
Agencies with human SDRs excel at personalized, relationship-driven outreach and complex sales cycles where nuance matters. They're ideal for high-touch industries like enterprise software or professional services. AI lead generation platforms such as 11x excel at continuous automation, data enrichment, and multi-channel sequencing at scale—perfect for companies with clear ICPs and repeatable sales motions.
Request case studies in your industry, review sample messaging, and verify the depth of CRM integration. The best partners provide transparent reporting, share KPIs around SQL conversion (not just MQLs), and align on strategy regularly. Avoid providers promising unrealistic results or lacking clear targeting methodologies.
Self-serve data tools start at $20–$100 monthly. Full-service lead generation agencies typically charge $3,000–$10,000+ per month with 3–6 month minimums. AI SDRs such as 11x fall in between at $1,000–$5,000+ monthly, pricing based on volume and features. Many companies find that AI platforms deliver stronger ROI than traditional agencies due to continuous automation and faster optimization cycles.
Focus on ROI rather than cost alone. If outsourcing costs $4,000 monthly but generates 20 qualified opportunities worth $50,000 each, the return justifies the investment. Compare this to hiring an SDR at $80,000–$120,000 annually plus benefits, training, and ramp time. Most companies find that outsourcing delivers faster time-to-value and more predictable results.
The future of B2B lead generation is hybrid. AI SDRs will handle data collection, enrichment, messaging, outreach, and follow-ups, while humans lead strategy and relationship management. Expect faster campaign ramp-up, more accurate metrics, and tighter alignment between sales and marketing. Over time, outsourcing lead generation will blur the line between “agency” and “software,” giving companies scalable ways to meet their business needs and expectations around the target audience.
