The Best Marketing Automation Tools for Marketing Agencies in 2026

ActiveCampaign is one of the only platforms on this list that names your exact situation directly: Active Intelligence 2.8's brand memory stores each client's voice, custom instructions, and visual assets separately, so switching between accounts doesn't mean re-explaining tone from scratch every time. The 94.2% deliverability rate also matters more across a roster than it would for one brand, since a deliverability problem on one client account can spill into how the platform performs for the others if you're not watching it closely.

Starter at $15/month caps automation actions at 5, which isn't enough for a real client campaign, so budget for Plus at $49/month as your realistic floor per account. The CRM being an add-on rather than included is worth flagging to clients who assume sales pipeline tracking comes bundled in.

For the DTC and eCommerce brands on your roster, Klaviyo's depth is hard to match: the built-in CDP unifies behavioral and transactional data in real time, and the Shopify integration means abandoned cart, post-purchase, and win-back flows work out of the box rather than requiring custom setup for every new client store. K:AI's Marketing Agent reading a client's website to build launch-ready campaigns also cuts real setup time when you're onboarding a new account.

Pricing scales by active profile count per account, which means a roster of several mid-size eCommerce clients needs genuine cost modeling before you commit, since a client with a large but low-engagement list can get expensive fast. Reserve Klaviyo for the clients where eCommerce behavioral depth is the actual differentiator, not as your default for every account type.

Mailchimp's biggest advantage for an agency isn't a feature, it's recognition: most small-business clients have already heard of it or used it themselves, which shortens the conversation when you're proposing a platform and makes handoff easier if a client ever wants to take the account in-house. The free plan up to 500 contacts is a genuine way to run a smaller client's early-stage email program without billing them for a dedicated automation line before the list has grown enough to need one.

Where it falls short is behavioral automation depth for eCommerce-heavy accounts, Klaviyo will out-segment it every time on that front. Use Mailchimp for the general small-business and content-driven clients on your roster, and reach for Klaviyo when a client's program is genuinely built around purchase behavior.

Brevo's pricing by emails sent rather than contacts stored is a genuine structural advantage across a multi-client roster: a client with a large imported list but selective, segmented sending costs far less here than on a per-contact platform, which matters when you're managing several accounts of very different list sizes under one agency budget. For any European client, the EU-native GDPR architecture and data residency are also a real answer rather than a compliance page bolted onto a US product.

Marketing automation itself is gated to the Standard plan and above, so the Starter tier is really just email sending and segmentation, not the workflow builder a client retainer usually implies. Budget Standard as the realistic floor per client account if automated journeys are part of what you're delivering.

Ortto's combination of a built-in CDP, journey automation, analytics dashboards, and live chat support in one product is explicitly positioned around agencies running multiple client accounts, with white-label delivery available for presenting the platform under your own brand rather than a vendor's. For SaaS and tech clients specifically, the CDP-backed segmentation means automations respond to real product usage data instead of static list rules from day one.

Pricing requires a sales conversation with no published rate card, which slows down the kind of quick per-client cost modeling you need when quoting a new retainer, and the recent Canva acquisition introduces real uncertainty about where pricing and the roadmap go next. Confirm current terms directly before committing a client account to it.

For the most technically sophisticated SaaS client on your roster, one where product usage events should genuinely drive lifecycle messaging, Customer.io's event-driven data model and unlimited API calls on every plan are hard to replicate elsewhere. The Startup Program offering 12 months free for companies that have raised under $10 million is also worth flagging to an early-stage client who can't yet justify a full retainer line for automation.

The jump from $100/month Essentials to $1,000/month Premium is a steep gap with nothing in between, and getting real value out of the platform requires a client whose product is already instrumented with event tracking, which usually means engineering involvement you may need to coordinate on their side. Reserve this for the one or two roster clients whose product-led model actually needs it, not as a general-purpose pick.

Unlimited email sends and AI content tools on every paid tier, starting at €13.12/month, make budgeting across several client accounts more predictable than platforms that charge per send or gate AI features to upper tiers. For a content-driven client running webinars or a paid newsletter alongside email, the Creator plan bundling webinar hosting and a course creator with the full automation stack is a genuinely unusual combination that saves that client from paying for a separate tool entirely.

The integration library at 150+ connections is notably narrower than ActiveCampaign's 1,000+, so verify a specific client's existing stack connects cleanly before committing the account to GetResponse. Advanced segmentation also requires the Marketer plan, so treat Starter as too limited for a real client program.