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Offering email marketing services to clients? Don’t just default to the biggest names!
Why stick with tools full of features you’ll never use, when you could choose something simpler that still gets results?
Each email marketing software has its sweet spot, with a mix of features designed to suit different types of clients and campaign goals. Using the right one for your agency’s needs can save your team time, minimize frustration, and even save money (no more overpaying!)
Below, we’ll explore what each one does best to help you find the right fit for your agency, no matter how varied your clients’ needs and industries are
A round-up of the best email marketing software to help you deliver smarter, faster results for clients:

Klaviyo is best known as Shopify’s recommended email partner, but the platform has sophisticated B2C CRM features and lots of integrations that make it a powerful ally for ecommerce brands. It combines email marketing, marketing automation, and a customer data platform (CDP) for relationship-driven brands to leverage customer insights in one app.
However, these advanced capabilities come with an increased learning curve, and the cost for larger email lists escalates more quickly than lighter, less data-focused platforms.
Pricing for 1501 to 2500 active profiles*:
Note: Paid add-ons include reviews, advanced marketing analytics, and Klaviyo Data Platform.
*Active profiles are Klaviyo's term for email contacts, subscribers, and people who engage with your messages.

Braze is an enterprise-level customer engagement platform with omnichannel marketing features targeted at mobile marketing and mobile-first campaigns. Think advanced analytics for segmenting and targeting mobile users, Braze Data Platform, and funnel drop-off reporting.
Braze helps brands to engage customers where they’re at—on smaller screens and devices—and maintain a cohesive, on-brand experience, no matter the channel. Trusted by global brands with its reliability and deliverability, Braze boasts its “sub-second latency, regardless of your data and send volumes.”
An online source states that Braze’s pricing starts from $60,000/year.

Formerly known as ConvertKit, they’ve rebranded to Kit in 2024 to reflect their growing feature list and reposition as an email platform built for the creator economy.
It’s not just for content creators, bloggers, podcasters, course creators, streamers, and digital entrepreneurs; authors, subject matter experts with an online following, musicians, actors, and entertainers are also part of their creator community.
Kit’s promise is a simple and effective email marketing software to help creators grow and monetize their social following. The user-friendly interface is easy for solopreneurs to get started, even if you’re not tech-savvy or if it’s your first time sending out a newsletter.
All Kit plans have unlimited email sending. For 3000 email subscribers, these are the subscription prices (paid yearly):

ActiveCampaign positions itself as an autonomous marketing platform that “figures out the next best move, aligns it to your goals, and then does it for you.” If you aren’t already using your own AI agents for marketing work, you’ll get to experience them here with the Active Intelligence feature. The interface is conversational, so there’s no code or technical expertise needed to set up complex automation workflows with precise targeting and sophisticated triggers.
Pricing for email marketing and 2,500 contacts starts at:
🔗 Want to explore more ways to use AI across your marketing workflows? Check out our list of the best AI tools for marketing agencies.

Drip is behavior-driven email marketing software that’s known for its e-commerce automation and segmentation capabilities. With an outstanding deliverability rate, hyper-customized emails and forms, Drip makes it easy for B2C businesses to deliver significantly higher engagement and revenue through personalized email flows.
Brands can tap into onsite pop-ups (AKA email pop-ups) to guide first-time visitors towards being potential customers—all fully integrated with email workflows. The drag-and-drop designer makes it easy to create a lead generator that’ll grow an email subscriber list, host giveaways, or run promotions with a countdown timer.
Drip has transparent pricing that’s based on the number of email contacts.

Mailchimp is an all-in-one, simple marketing platform for agencies to scale email, social, and digital campaigns for their clients. It’s versatile and easy to use for a diverse range of clients, from e-commerce to non-profits. The dependable platform works well for agencies that prioritize ease of use and reliable functionality.
However, clients who rely on long, multi-touch nurture journeys and CRM-native automation won’t find Mailchimp ideal. Designed with ease of use for small and medium businesses in mind, it falls short on advanced capabilities such as lead scoring and cross-channel attribution reporting, which are often essential for complex marketing campaigns.
Mailchimp’s starting prices are based on the number of contacts you need. For 2500 contacts, paid plans start from:
*Mailchimp sometimes runs promos for new users.

Brevo stands out with its email-based pricing model (rather than contact-based) and robust AI features. It’s not just email; they’re an all-in-one marketing platform that also combines SMS, WhatsApp, CRM, marketing automation, landing pages, forms, and transactional messaging.
Their generative AI features are particularly powerful, making it a good option for agencies planning on leveraging artificial intelligence heavily into email copywriting and management. The platform is also great for teams that need comprehensive marketing automation without enterprise-level pricing.
Base plan prices start low, with the option of add-ons for features such as additional users, landing pages, and dedicated IP. These are the annual prices for one account:

Campaign Monitor delivers premium email marketing with standout design and agency-friendly tools. Its multi-client dashboard, white-labeling, and client billing streamline account management, while 100+ professional templates and powerful branding controls make it ideal for design-driven campaigns. Seamless integrations with major CRMs and e-commerce platforms—including Salesforce, WordPress, Shopify, Unbounce, and Intercom—fit right into agency marketing tech stacks.
Prices based on 501 to 2500 contacts for an annual subscription:
*Add-ons are available at an additional cost: Non-human click filter, engagement segments, countdown timer, and time zone sending.

Constant Contact is an easy-to-use email marketing software with exceptional analytics capabilities, marketing automation, and built-in event management tools. It even offers social posting and reporting to Facebook, Instagram, and LinkedIn on all plans. The platform provides a comprehensive social media marketing integration, making it particularly valuable for agencies managing clients with diverse marketing needs.
The Agency Partner Program gives your agency exposure to thousands of potential clients, sign-up bonuses, 18% referral commission, and a centralized portal to manage multi-client campaigns. The platform excels for agencies serving nonprofits, associations, or event-based businesses.
🔗 Want to level up your analytics across all campaigns? Check out our guide to the best agency reporting software.
Annual pricing for 1001 to 2500 contacts:
🔗 Related article: Best Social Media Management Tools for Marketing Agencies

Mailmodo differentiates itself by enabling interactive AMP emails that allow recipients to complete actions like form submissions, bookings, and purchases—without leaving the email. They also offer exceptional segmentation features, including the option to create audience segments with AI’s assistance. Are building automated email sequences and triggered campaigns too complex in other tools? You can do it visually in Mailmodo.
Annual pricing based on 2500 contacts:

Omnisend has exceptional features for ecommerce businesses, with multi-channel marketing combining email, SMS, and push notifications. They have strong personalization options, which can increase campaign success rates. The platform includes all features across all pricing tiers, with differences mainly in sending volumes and contact limits. We find it particularly suitable for agencies managing Shopify-based businesses or online retail clients.
Monthly pricing based on 2001 to 2500 contacts:

GetResponse is one of the few all-in-one marketing platforms that include landing pages, conversion funnels, and built-in webinar hosting. This means agencies can handle everything—from capturing leads to running nurture campaigns and hosting live or evergreen webinars—all in one place.
It’s a great fit for agencies running lead generation, nurture, or webinar-based campaigns for clients, especially those in B2B, SaaS, or e-commerce, who need a reliable and scalable way to manage multi-step campaigns efficiently.
* Discounts available for annual plans (up to 18% off) and nonprofits.
Choosing the right email marketing software comes down to how you plan to use it. Here’s how to narrow down your options:
1. Start with your own (or your client’s) goals
Before comparing tools, get clear on what success looks like. Are you trying to drive online sales, nurture leads, or keep existing customers engaged? Your main goal will determine which features to prioritize.
2. Check the non-negotiable features you need
The best email marketing software (for any business type) will offer:
Once those basics are covered, you can focus on features that match your client type.
E-commerce brands rely on data-driven automations to boost sales. This means that your software should let you use customer behavior and purchase history to personalize every message.
Look for:
Service-based businesses rely on relationship-building and lead nurturing, not one-off sales. This means that your tool should combine email marketing with CRM and automation features to simplify how you communicate with clients.
Look for:
💡 Quick tip: If your agency works with both types of clients, go for a platform that offers sub-accounts or workspaces. This way, you can manage multiple client accounts securely without mixing data or logins.
🔗 Want to learn more about improving your agency tech stack? Check out our post on the best tools for agency operations.
Every day spent waiting for account access is a day you're not launching campaigns, delivering results, or generating revenue.
Leadsie is a client onboarding software that helps agencies request and receive access to client marketing, advertising, and social media accounts with one secure link. Instead of managing endless emails, permission requests, and troubleshooting sessions, you send a link to your client, they approve the permissions you've requested, and you get access in minutes, not days.
Clients can grant access to Meta, Google, LinkedIn, TikTok, Shopify, and 14+ other marketing platforms without sharing passwords.

✅ Request, manage, and remove client access from one place
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✅ Create a professional onboarding experience that helps retain clients
✅ Keep access secure with 100% GDPR and CCPA-compliant workflows
💬 "I never want to do onboarding without Leadsie!" - Alyssa, Meta Ads Manager
🎁 Start your free 14-day trial today —no credit card required.
P.S. It's risk-free, and you get to keep your account connections after the trial ends. 🙌
Automate your onboarding now & join 1500+ agencies using Leadsie.
14 day unlimited trial
Extend until you onboard a client
No credit card required
Keep access to accounts if you cancel
Approved by Meta, Google & TikTok
Secure & 100% GDPR compliant
Automate your onboarding now & join 1000+ agencies using Leadsie.
Approved by Meta, Google & Tiktok
Keep access to accounts if you cancel
Secure & 100% GDPR compliant

If you’re working with a small client base, Brevo or Kit are budget-friendly and simple to use. They have all the essentials (automation, templates, and basic reporting) without enterprise-level pricing.
If you’re growing fast, ActiveCampaign, GetResponse, and Braze are built for scale. They offer automation, API integrations, and flexible pricing for agencies managing many clients or large contact lists.
ActiveCampaign, Campaign Monitor, Brevo, and GetResponse MAX include dedicated agency dashboards or multi-account setups. They let you switch between client accounts easily while keeping data and billing separate.
Choose a platform with strong analytics and reporting. Tools like Constant Contact, Klaviyo, and Mailchimp let you share or white-label reports showing open rates, conversions, and revenue attribution, so you can easily prove the value of your work.
Questions unanswered? Check out our help center or get in touch 🤠