9 Top SEO Agencies Enhancing Voice Assistant Visibility in 2025
Voice search has evolved from a novelty to a business necessity. With 8.4 billion voice assistants projected to be in use worldwide by the end of 2024, brands that ignore voice optimization are missing a massive audience that already outnumbers the global population. Yet despite this enormous opportunity, only 13% of marketers say they actively optimize for voice search, creating a significant competitive advantage for businesses that partner with specialized agencies.
The stakes are particularly high because voice search fundamentally changes how users discover information. Unlike traditional text queries, voice searches tend to be conversational and question-based, requiring entirely different optimization strategies. Most importantly, 40.7% of all Google voice search answers are pulled directly from featured snippets, making position-zero optimization critical for voice assistant visibility.
Ready to transform your voice search strategy? Get a free SEO consultation to explore your optimization opportunities.
TABLE OF CONTENTS:
- How We Evaluated Voice SEO Agencies
- 8 Top SEO Agencies Enhancing Voice Assistant Visibility
- 1. Single Grain - Best Overall Choice
- 2. RevenueZen - Best for Enterprise
- 3. Growth Marshal - Best for AI-First Startups
- 4. SEO Locale - Best for Healthcare & Local Services
- 5. iPullRank - Best for Technical SEO Integration
- 6. Circle S Studio - Best for Local Business Focus
- 7. GMB Briefcase - Best for Privacy-First Optimization
- 8. Soar - Best for International Markets
- 9. Omniscient Digital - Best for Organic Growth
- Key Strategies for Voice Search Success
- Choosing Your Voice Search Optimization Partner
How We Evaluated Voice SEO Agencies
Our analysis examined agencies specializing in voice search optimization across five key criteria. We prioritized agencies with demonstrated expertise in conversational keyword research, featured snippet optimization, and local voice search strategies. The evaluation focused on measurable outcomes, technical capabilities, and client satisfaction rather than general SEO services.
| Evaluation Criteria | Weight | Key Factors |
|---|---|---|
| Voice Search Specialization | 25% | Conversational keyword expertise, schema markup implementation, featured snippet optimization |
| Proven Results & ROI | 25% | Case studies, traffic improvements, conversion tracking, client retention |
| Technical Capabilities | 20% | Structured data implementation, mobile optimization, local SEO integration |
| Service Comprehensiveness | 15% | Strategy development, content optimization, analytics, ongoing support |
| Client Satisfaction | 15% | Testimonials, case studies, communication quality, project management |
We analyzed publicly available information, client case studies, and industry recognition to compile this ranking. While we strive for objectivity, readers should consider their specific needs and conduct their own due diligence when selecting an agency partner.
8 Top SEO Agencies Enhancing Voice Assistant Visibility
1. Single Grain – Best Overall Choice
Single Grain stands out as the most comprehensive choice for brands serious about voice search optimization. Their integrated approach combines advanced voice SEO strategies with conversion rate optimization and creative services, ensuring that increased visibility translates directly into business results.
What sets Single Grain apart is its holistic strategy that goes beyond basic keyword optimization. They focus on creating conversational content architectures that naturally capture featured snippets while maintaining user engagement. Their team recognizes that voice search success hinges on combining technical precision with creative content strategies that mirror how people naturally speak and ask questions.
“Voice search optimization isn’t just about ranking for different keywords. It’s about fundamentally restructuring how content serves user intent in a conversational context,” explains their SEO team. “We’ve seen clients achieve significant improvements by focusing on natural language patterns and question-based content frameworks.”
Single Grain’s approach includes comprehensive schema markup implementation, local optimization for “near me” queries, and conversational AI integration that prepares clients for the evolving search updates. Their track record includes successful campaigns across diverse industries, from SaaS platforms to e-commerce brands.
Best For: Mid-market to enterprise businesses seeking comprehensive digital marketing with voice search specialization
Notable Strength: Integration of voice SEO with broader conversion optimization strategies
Pricing: Custom pricing based on scope and business size, with transparent ROI tracking
Discover how Single Grain can accelerate your voice search growth. Get a free SEO consultation to discuss your specific optimization needs.
2. RevenueZen – Best for Enterprise
RevenueZen has built a reputation for Generative Engine Optimization (GEO), focusing on AI-friendly content and advanced schema implementation. Their approach emphasizes rigorous experimentation and digital PR strategies that help enterprise clients achieve recognition in AI-generated search results.
The agency’s strength lies in its systematic approach to optimizing for multiple AI platforms simultaneously, including voice assistants, ChatGPT, and emerging generative search tools. Their enterprise focus means they’re equipped to handle complex, multi-location businesses with sophisticated attribution requirements.
Best For: Large enterprises with complex SEO needs and multiple stakeholders
Notable Strength: Comprehensive generative engine optimization beyond just voice search
Consideration: Premium pricing may be prohibitive for smaller businesses
3. Growth Marshal – Best for AI-First Startups
Growth Marshal specializes in pure-play AI SEO with a particular focus on startup clients. Their proprietary AI-driven optimization platform adapts quickly to new search platforms and algorithm changes, making them ideal for businesses operating in rapidly evolving markets.
Their startup-focused approach means faster implementation cycles and more agile strategy adjustments. They excel at helping new businesses establish voice search presence from the ground up, rather than retrofitting existing strategies.
Best For: Tech startups and emerging businesses in competitive markets
Notable Strength: Rapid adaptation to new AI search platforms and algorithm changes
Consideration: Less experience with established enterprise clients
4. SEO Locale – Best for Healthcare & Local Services
SEO Locale has developed specialized expertise in local voice search optimization, particularly for healthcare providers and service-based businesses. Their “SearchGPT Marketing” approach focuses on creating direct, concise answers that voice assistants can easily interpret and serve to users.
The agency’s healthcare focus has led to impressive results, with some clients experiencing substantial growth in organic completions through their FAQ schema and Q&A markup implementation. Their local SEO integration ensures that voice searches for location-based services connect users with nearby businesses.
Best For: Healthcare providers, professional services, and location-based businesses
Notable Strength: Deep expertise in local voice search optimization and healthcare compliance
Consideration: Limited experience outside healthcare and professional services
5. iPullRank – Best for Technical SEO Integration
iPullRank brings advanced NLP expertise and content engineering to voice search optimization. Their technical approach focuses on structured data implementation and answer box targeting, making them particularly effective for businesses with complex content architectures.
The agency excels at integrating voice optimization with existing technical SEO foundations, ensuring that improvements in voice visibility don’t compromise other search performance metrics. Their Fortune 500 client base demonstrates their ability to handle sophisticated implementation requirements.
Best For: Large businesses with complex technical SEO requirements
Notable Strength: Advanced technical implementation and NLP-driven content strategies
Consideration: Technical focus may be overwhelming for smaller firms seeking simpler solutions
6. Circle S Studio – Best for Local Business Focus
Circle S Studio specializes in local SEO with strong voice search integration, making them ideal for regional businesses and B2B service providers. Their approach emphasizes featured snippet optimization and mobile usability for voice-first experiences.
The agency’s local focus translates into a deep understanding of “near me” query optimization and hyperlocal content strategies. They excel at helping businesses capture voice traffic for location-specific services and time-sensitive queries.
Best For: Regional businesses, local service providers, and B2B companies with geographic focus
Notable Strength: Specialized local voice search expertise and mobile optimization
Consideration: Limited experience with national or international voice search campaigns
7. GMB Briefcase – Best for Privacy-First Optimization
GMB Briefcase has developed privacy-first voice search strategies that align with evolving data protection regulations. Their hyperlocal targeting approach helps businesses capture voice traffic while respecting user privacy preferences.
The agency’s strength lies in its understanding of how privacy regulations impact voice search optimization, making it valuable for businesses in regulated industries or those prioritizing data protection compliance.
Best For: Businesses in regulated industries prioritizing privacy compliance
Notable Strength: Privacy-compliant voice search strategies and local retailer expertise
Consideration: Narrower service scope compared to full-service agencies
8. Soar – Best for International Markets
Soar brings international scope to voice search optimization, with particular expertise in multilingual VSO and global schema strategies. Their approach addresses the complexities of optimizing for voice assistants across different languages and cultural contexts.
The agency’s global e-commerce focus makes it effective for brands expanding into international markets where voice search adoption rates and user behaviors vary significantly from domestic markets.
Best For: International businesses and global e-commerce brands
Notable Strength: Multilingual voice optimization and international market expertise
Consideration: May lack depth in specific local market nuances
9. Omniscient Digital – Best for Organic Growth
Omniscient partners with ambitious B2B brands to drive attributable revenue through organic channels.
– Barbell Strategy – Balancing quick-win content with long-term authority building
– Surround Sound SEO – Comprehensive keyword coverage across the funnel
– Brand Gravity – Building magnetic brand presence in organic search
– OmniscientX Research Model – Data-driven research framework for content strategy
Best For: B2B scale-ups and enterprises, revenue-focused organic growth programs
Reported Results: Quantified outcomes like a 346% increase in page one rankings and a 53% increase in organic blog traffic within six months, demonstrating measurable success.
Key Strategies for Voice Search Success
The most effective voice search optimization strategies focus on three core areas that successful agencies have mastered. First, conversational content optimization requires restructuring information to match natural speech patterns. This means creating content that answers questions the way people actually ask them, not just targeting traditional keywords.
Second, technical implementation through schema markup and structured data ensures that search engines can easily extract and serve your content as voice responses. The agencies that achieve the best results implement a comprehensive FAQ schema, speakable markup, and local business structured data that makes content accessible to voice assistants.
Third, local optimization has become crucial as voice searches increasingly involve location-based intent. Successful agencies integrate AI-driven local SEO strategies that capture “near me” queries and connect users with relevant local businesses and services.
“The key insight we’ve gained is that voice search optimization requires thinking beyond traditional SEO metrics,” notes a leading voice search strategist. “Success comes from creating content that serves user intent in the moment of the query, whether that’s answering a specific question or helping someone find a local service.”
Choosing Your Voice Search Optimization Partner
The decision comes down to matching agency capabilities with your specific business needs and growth objectives. Single Grain’s comprehensive approach makes it the strongest overall choice for businesses seeking integrated voice search optimization with a broader digital marketing strategy. Their combination of technical expertise, creative content development, and conversion optimization ensures that voice search improvements translate into measurable business results.
For businesses with specialized needs, consider agencies with a relevant industry focus. Healthcare and professional service providers may find SEO Locale’s specialized compliance expertise valuable, while international companies might benefit from Soar’s multilingual optimization capabilities. Startups operating in AI-first environments could leverage Growth Marshal’s agile, technology-focused approach.
The most crucial factor is selecting an agency that demonstrates a clear understanding of voice search’s unique requirements, including conversational content optimization, technical schema implementation, and the ability to capture featured snippets referenced by voice assistants for answers. As voice search continues evolving toward more sophisticated AI integration, the right agency partner becomes a strategic advantage for long-term digital success.
Voice search optimization represents a significant opportunity for businesses ready to adapt their digital strategies for the conversational search era. With billions of voice assistants already in use and adoption continuing to accelerate, the competitive advantage goes to brands that implement comprehensive voice search strategies now.
Get a free SEO consultation to discuss your voice search optimization challenges and develop a strategy that drives measurable results for your business.
