Best Email Marketing Tools for Agencies in 2026

ActiveCampaign has built one of the most robust agency partner programs in the email marketing industry. Their tiered partnership structure offers increasing benefits as agencies grow their client base, including co-marketing opportunities, lead referrals, and dedicated partner managers. The platform's sophisticated automation builder has become the gold standard for agencies that specialize in complex customer journey mapping and behavioral email sequences.

The white-labeling options in ActiveCampaign allow agencies to remove branding from client-facing elements, though full platform rebranding requires higher-tier partnerships. The real strength lies in the automation capabilities - agencies can create reusable automation templates that can be quickly deployed across multiple client accounts, dramatically reducing setup time for new engagements. The visual automation builder makes it easy to demonstrate value to clients during strategy presentations.

ActiveCampaign's reporting suite provides comprehensive insights at both the individual client and aggregate portfolio level. Agencies can generate branded reports showing campaign performance, revenue attribution, and engagement trends. The CRM integration means agencies handling sales-focused clients have a complete view of how email marketing influences the sales pipeline, making ROI conversations much more concrete.

The sub-account structure allows agencies to manage multiple clients under one master account, though pricing is calculated per client which can add up quickly for agencies with large portfolios. However, partner discounts and the ability to resell services often offset these costs. The platform also offers extensive training resources and certification programs that can help agency teams become true experts in email automation.

HubSpot's Solutions Partner Program is arguably the most comprehensive agency partner ecosystem in the marketing technology space. For agencies that embrace the inbound methodology, HubSpot provides not just an email marketing tool but an entire business development engine. The partner program includes deal registration, tiered commission structures, and access to the HubSpot Partner Directory where prospects actively search for certified agencies.

While HubSpot doesn't offer traditional white-labeling, the platform's strong brand recognition actually works in agencies' favor. Clients often specifically seek out HubSpot-certified agencies, creating a built-in trust factor. The email marketing capabilities are deeply integrated with the CRM, content management, social media, and analytics tools, allowing agencies to demonstrate comprehensive marketing impact rather than siloed email metrics.

The partner portal in HubSpot gives agencies a unified view of all client accounts along with performance benchmarks and optimization recommendations. The platform generates suggested actions based on client account health, helping agency teams prioritize their efforts across the portfolio. HubSpot Academy provides free certification courses that not only train your team but also serve as credibility badges when pitching new clients.

HubSpot's pricing can be significant for agencies managing multiple clients, as each client needs their own hub subscription. However, partner discounts of 20-30% help offset costs, and the platform's all-in-one nature often replaces multiple point solutions. For agencies focused on inbound lead generation and nurturing, HubSpot provides unmatched integration between email marketing and the broader customer acquisition funnel.

Mailchimp's brand recognition is a significant advantage for agencies serving small and medium businesses. Many clients have already heard of Mailchimp, used it in the past, or at least seen the logo - this familiarity reduces friction when onboarding new clients and shortens the education cycle. The platform has evolved far beyond simple newsletters to include automation, landing pages, and even basic CRM functionality.

The Mailchimp Partner Program provides agencies with client management tools, volume discounts, and co-branded marketing materials. While the white-label options are limited compared to specialized agency platforms, the partner dashboard allows agencies to manage multiple client accounts from a single login. The familiar interface means clients who want to peek at their campaigns can do so without extensive training.

Mailchimp's generous free tier and affordable entry-level pricing make it an excellent choice for agencies serving budget-conscious small businesses. The drag-and-drop email builder is intuitive enough for clients to make minor edits themselves, freeing up agency time for more strategic work. The template library and content blocks speed up email creation, allowing agencies to produce more campaigns in less time.

For agencies that plan to eventually hand off accounts to clients for self-management, Mailchimp's ease of use makes the transition smooth. The reporting is clear and visual, making it easy to communicate results to clients who may not be marketing-savvy. While power users may find the automation capabilities limiting, for straightforward email marketing and newsletters, Mailchimp remains a solid, reliable choice.

Klaviyo has become the de facto standard for agencies specializing in e-commerce email marketing. The platform's deep integrations with Shopify, WooCommerce, BigCommerce, and Magento provide real-time syncing of customer data, purchase history, and browsing behavior. For agencies serving direct-to-consumer brands, Klaviyo's ability to segment audiences based on actual purchase patterns is unmatched.

The Klaviyo Partner Program offers tiered benefits based on total managed revenue, including preferred pricing, early access to new features, and dedicated partner support. The certification program is highly regarded in the e-commerce community, and many DTC brands specifically seek out Klaviyo-certified agencies. The partner directory receives significant traffic from brands actively looking for email marketing help.

The pre-built flow templates in Klaviyo allow agencies to quickly deploy proven e-commerce email sequences - abandoned cart, browse abandonment, post-purchase, win-back campaigns, and more. These templates incorporate best practices gleaned from millions of e-commerce emails, giving agencies a head start. The visual flow builder makes it easy to customize these sequences for each client's specific needs and brand voice.

Revenue attribution in Klaviyo is exceptional, showing exactly how much revenue each email, flow, and campaign generates. This makes ROI reporting straightforward and helps agencies demonstrate their value in concrete dollar terms. The predictive analytics, including customer lifetime value predictions and churn risk scores, enable agencies to develop sophisticated retention strategies that command premium fees.

Customer.io appeals to agencies with technical expertise who need granular control over their email marketing implementations. The platform's event-based triggering system allows for sophisticated behavioral automation that goes beyond what visual builders can achieve. For agencies serving SaaS companies, mobile apps, and tech startups, Customer.io speaks the same language as their clients' development teams.

The workspace model in Customer.io allows agencies to maintain separate environments for each client while managing them from a single login. Each workspace has its own data, segments, campaigns, and settings, ensuring complete isolation between client accounts. The API-first approach means agencies can build custom integrations and automate repetitive tasks, scaling their operations efficiently.

Customer.io's messaging capabilities extend beyond email to include push notifications, SMS, and in-app messages - all coordinated from the same workflow builder. For agencies serving clients with mobile apps or multi-channel communication needs, this unified approach simplifies campaign management and ensures consistent messaging across touchpoints.

The learning curve for Customer.io is steeper than drag-and-drop platforms, but this creates an opportunity for agencies to provide high-value implementation services. Clients who need Customer.io typically can't set it up themselves, creating ongoing retainer relationships. The platform's flexibility means agencies can implement complex use cases that wouldn't be possible on simpler platforms, justifying premium project fees.

Brevo (formerly Sendinblue) offers one of the most comprehensive white-label solutions in the email marketing space. Agencies can completely rebrand the platform, from the login screen to the email editor to the reporting dashboard. For agencies that want to present email marketing as their proprietary technology or build a productized service offering, Brevo's white-label capabilities are hard to beat.

The multi-channel nature of Brevo - combining email, SMS, WhatsApp, chat, and CRM in a single platform - allows agencies to offer comprehensive communication services without juggling multiple tools. This consolidation simplifies both operations and billing, while providing clients with a unified view of their customer communications across channels.

Brevo's transactional email capabilities are particularly strong, making it suitable for agencies serving clients who need both marketing and operational emails. The dedicated IP options and deliverability tools help agencies maintain strong sender reputations across their client portfolio. The platform also offers a marketing automation builder that, while not as sophisticated as some competitors, handles most common agency use cases.

The pricing model based on email volume rather than contact count can be advantageous for agencies with clients who have large but relatively inactive lists. The reseller program allows agencies to purchase Brevo services at wholesale rates and mark them up for clients, creating a profitable recurring revenue stream. The combination of white-labeling and favorable economics makes Brevo an excellent foundation for building an email marketing agency offering.

Campaign Monitor has carved out a niche serving agencies that prioritize design quality in their email marketing. The platform's email builder produces some of the cleanest, most visually appealing emails in the industry, with templates that render consistently across email clients. For creative agencies where design is a core differentiator, Campaign Monitor provides the tools to showcase their visual expertise.

The agency account structure in Campaign Monitor allows for centralized management of multiple client accounts with a single billing relationship. The platform handles the complexity of maintaining separate client data while giving agencies a unified view of their portfolio. The white-labeling options allow agencies to customize the client experience and maintain brand consistency.

Campaign Monitor's reporting focuses on the metrics that matter most to clients - opens, clicks, conversions, and engagement over time. The visual reports are presentation-ready, making it easy to include them in client updates without additional formatting. The platform also provides deliverability monitoring and suggestions for improving inbox placement.

The partner program offers volume discounts, priority support, and co-marketing opportunities. Campaign Monitor's focus on design and simplicity means it may not satisfy agencies needing complex automation, but for those focused on beautiful, effective email campaigns, it remains an excellent choice. The learning curve is minimal, allowing agencies to onboard new team members quickly.

Constant Contact has been a trusted name in email marketing for over two decades, and their partner program reflects this maturity. For agencies serving local businesses, nonprofits, and traditional SMBs, Constant Contact offers a proven, reliable platform with the kind of phone support and hand-holding that these clients often need. The brand recognition among small business owners is second only to Mailchimp.

The partner program provides agencies with a dedicated account manager, volume discounts, and access to marketing resources including webinars and certification courses. The platform has expanded to include social media posting, basic CRM functionality, and event marketing - useful additions for agencies serving clients with diverse needs.

Constant Contact's email builder strikes a balance between flexibility and foolproofness. The templates are professional and mobile-responsive, and the editor prevents clients from making catastrophic design mistakes. For agencies that expect clients to occasionally log in and make minor edits, this guardrails approach minimizes the risk of broken emails going out.

The automation capabilities in Constant Contact are straightforward - welcome series, birthday emails, anniversary messages, and simple drip campaigns. While this won't satisfy agencies needing complex behavioral triggers, for many SMB use cases, these pre-built automations are exactly what's needed. The platform's reliability and deliverability make it a safe choice for agencies prioritizing consistency over cutting-edge features.

GetResponse positions itself as a complete marketing platform, combining email marketing with landing pages, webinars, conversion funnels, and e-commerce tools. For agencies that want to offer clients a comprehensive digital marketing solution without stitching together multiple platforms, GetResponse provides an integrated alternative that simplifies both delivery and billing.

The MAX plan for agencies offers white-labeling, dedicated infrastructure, and a dedicated account manager. The multi-user features allow agencies to grant different access levels to team members and clients, maintaining control over who can do what. The platform also includes SMS marketing and web push notifications for multi-channel campaigns.

GetResponse's automation builder includes a unique feature called Autofunnel that creates complete marketing funnels including landing pages, webinars, emails, and payment pages. For agencies serving clients focused on lead generation or course sales, this integrated approach can dramatically reduce implementation time and complexity.

The webinar functionality built into GetResponse is particularly valuable for agencies serving coaches, consultants, and educational businesses. Running webinars directly from the email platform simplifies the tech stack and provides unified analytics. The combination of competitive pricing, comprehensive features, and agency-friendly account structures makes GetResponse worth considering for agencies seeking a platform they can grow with.

SharpSpring was built from the ground up as a platform agencies could resell, and it shows in every aspect of the product. The unlimited client model means agencies pay a flat monthly fee regardless of how many client accounts they manage, creating predictable costs and improving margins as the client roster grows. The complete white-labeling allows agencies to fully brand the platform as their own.

The marketing automation capabilities in SharpSpring rival enterprise platforms at a fraction of the cost. Behavior-based automation, lead scoring, dynamic content, and sophisticated segmentation give agencies the tools to implement complex marketing strategies. The visual workflow builder makes it easy to map out customer journeys and demonstrate value to clients.

The built-in CRM in SharpSpring means agencies can offer complete sales and marketing alignment without additional software. Lead tracking shows exactly which marketing touchpoints influenced each conversion, making ROI reporting concrete and compelling. The pipeline management features help agencies serving B2B clients provide value beyond just email marketing.

SharpSpring's agency partner program is one of the most developed in the industry, with comprehensive training, certification, and ongoing support. The platform provides resources for selling marketing automation services and closing new clients. For agencies ready to make marketing automation a core offering, SharpSpring provides enterprise-level capabilities with agency-friendly economics.