The 10 Best Klaviyo Email Marketing Agencies to Boost Your E-commerce Business

If you are an e-commerce company that requires advanced, behavior-driven marketing automation and customer segmentation, Klaviyo is the platform for you. 

But to use its advanced features and truly unlock its potential, you need an expert by your side. 

We regularly get clients who tell us they didn’t realize they could do something with Klaviyo or that Klaviyo had a specific feature. By using the right Klaviyo agency, you’ll ensure your email campaigns are optimized, personalized, and delivering a high return on investment.

So, we’ve compiled a list of the top 10 Klaviyo email marketing agencies that can help take your brand to the next level.

1. InboxArmy

InboxArmy is a full-service email marketing agency for all of your email needs—from strategy and template creation to automation, segmentation, and campaign. Our data-driven approach has a proven track record of improving customer retention and driving lifetime value. With a track record of helping e-commerce brands boost revenue, we’re the go-to choice for businesses looking for hands-on Klaviyo expertise.

Clutch Rating: 4.9 (63 reviews)

Google Rating: 4.9 (35 reviews)

Founded: 2016 

Employees: 120+

What sets us apart?

InboxArmy stands out due to its extensive experience with Klaviyo’s advanced features. As Klaviyo Silver Master partners, our team comprises some of the industry’s leading email experts. Our ROI-driven strategies ensure that every campaign is optimized for success. We offer SMS and push notification services and serve over 25 industries. With a deep understanding of email deliverability and customer retention, InboxArmy ensures that every email sent delivers tangible results. 

You can learn more about our award-winning team and how we help businesses maximize engagement and conversions here, and see what our customers say about us here.

2. Underground Ecom

Underground Ecom is an email marketing agency that works only with fast-growing direct-to-consumer brands. They focus on keeping customers, not just getting them. As a Klaviyo Master Elite Partner, they use advanced email strategies and a strong tech stack to help businesses grow customer value over time. So far, they’ve helped generate more than $165 million in tracked sales for clients around the world.

Clutch Rating: – (0 reviews)

Google Rating: 4.6 (11 reviews)

Founded: 2017

Employees: 150+

What sets them apart?

What sets them apart is how narrowly they focus. Instead of trying to do everything, they specialize in retention and customer lifetime value. Their deep Klaviyo expertise shows in both their Elite Partner status and the results they deliver—like a 37% higher ROI than what most Klaviyo users see. With over 150 global clients and a 9.9 NPS score, they’ve earned industry awards, including Email Marketing Agency of the Year in 2021.
Their team includes more than 150 specialists across the globe, all focused on retention. They’re also part of Supergroup, a vetted network of top marketing agencies. While email is their main channel, they use a full stack of tools to support retention, always tailored to how DTC brands work and the challenges they face.

3. Hustler Marketing

Hustler Marketing is a hands-on email marketing agency that builds custom strategies from scratch. They handle everything—campaign planning, design, automation, A/B testing, analytics, and deliverability. They don’t use templates. Instead, they mix creative work with deep data analysis to craft campaigns that match each client’s goals, audience, and industry. Their focus is simple: drive real, measurable results that matter to the bottom line.

Clutch Rating: 5 (14 reviews)

Google Rating: – (0 reviews)

Founded: 2018

Employees: 60+

What makes them different?

What makes them different is how tailored their approach is. They skip the one-size-fits-all playbook and build every strategy around the specific needs of each client. Every account gets a dedicated team.
They also run a detailed 7 to 10-day onboarding sprint that creates three key docs: a First Look Report that reviews performance, Copy Guidelines to match the brand voice, and Design Guidelines to keep visuals consistent. They’re certified across all major platforms like Klaviyo, Yotpo, Mailchimp, and HubSpot, which gives them the flexibility to work with whatever setup a brand is using. They’re also sharp on deliverability, optimization, and reporting, always tying results back to revenue—not just open rates or clicks.

4. UN/COMMON Agency

UN/COMMON offers full-scale Klaviyo email marketing services built around long-term retention, not just short-term wins. They manage both email and SMS, and they go beyond basic campaigns to help e-commerce brands grow in a steady, profitable way. As a Klaviyo Master Elite Partner, they back their strategy with smart consulting and clear planning, using data to build stronger customer relationships across multiple channels.

Clutch Rating: – (0 reviews)

Google Rating: – (0 reviews)

Founded: 2015

Employees: 45

What sets them apart?

What makes them different is how deeply they focus on sustainable growth. They don’t follow the churn-and-burn model that pushes quick sales. Instead, they create lifecycle marketing programs that include loyalty systems, subscription management, and real technical support—complete with in-house experts on deliverability and compliance. Their campaigns don’t stop at email and SMS. They reach customers wherever they’re most active, and that multichannel approach has helped clients triple their repeat purchases.
UN/COMMON blends strategy with action. They treat subscribers like VIPs, using custom offers and messaging that feels personal and relevant. Their work is grounded in data, but tailored to each brand’s market and business goals. Every recommendation is specific, thoughtful, and built to last.

5. Andzen

Andzen is a Klaviyo-focused email marketing agency that builds custom customer journeys for B2C brands. They’re the first Klaviyo Master Elite Partner in the APAC region and the fifth worldwide. That status reflects deep experience with Klaviyo’s CRM tools, especially for eCommerce.

Clutch Rating: – (0 reviews)

Google Rating: 4.8 (19 reviews)

Founded: 2014

Employees: 10-20

What makes them different?

Andzen’s Master Elite Partner status gives them access to features and support that most agencies don’t get. Their team knows how to get more out of Klaviyo—using segmentation, behavior tracking, and automation to build smarter email flows. They don’t just send emails. They plan full journeys that connect with customers at the right time. Their work regularly beats industry benchmarks in open rates, clicks, revenue per recipient, and ROI. And instead of just chasing one-off sales, they focus on long-term customer relationships that grow brand loyalty.

6. No Limit Email

No Limit Email is a results-driven Klaviyo email marketing agency that specializes in DTC brands and customer retention strategies. Their expert strategies and strong creative direction have given their clients an easily apparent upgrade to their emails.

Clutch Rating: 5 (21 reviews)

Google Rating: – (0 reviews)

Founded: 2020

Employees: 15-30

What sets them apart?

What makes No Limit Email unique is how skilled they are in up-leveling the email design of all of their clients. Their creative team brings a strong visual direction to every campaign. Their data-driven approach has led to a proven track record in revenue growth for DTC clients.

7. DIDO Agency

DIDO Agency is known for its performance-focused Klaviyo email marketing services. They have a highly refined client-onboarding process that helps their customers rapidly optimize their email marketing over six months. As Klaviyo partners, DIDO helps e-commerce brands stand out from their competition and drive revenue.

Clutch Rating: 4.8 (6 reviews)

Google Rating: 4.9 (18 reviews)

Founded: 2017

Employees: 25+

What makes them different?

Their highly optimized onboarding experience helps clients see rapid improvements within six months. As a Klaviyo Master Platinum Partner, they leverage advanced segmentation and pre-built integrations to give their customers advanced data analytics and segmentation.

8. Chronos Agency

Chronos Agency is a Klaviyo Master Elite partner that specializes in increasing customer lifetime value and retention for e-commerce brands. They create tailored retention strategies that drive repeat purchases for their clients and have a strong history of improving ROI and retention.

Clutch Rating: 4.8 (44 reviews)

Google Rating: – (0 reviews)

Founded: 2017

Employees: 80+

What sets them apart?

Chronos’s strength is their data-driven email nurture strategies. They create 100% custom email content tailored to the specific needs of each brand, which helps cultivate long-term customer engagement and growth.

9. The Email Marketers

The Email Marketers is a team of Klaviyo experts who specialize in crafting high-converting email campaigns for rapidly growing e-commerce brands earning 8 or 9 figures. They use AI-driven data to be one of the leaders in retention marketing. Their services include SMS, direct mail, campaign and subscription management, and loyalty programs.

Clutch Rating: 5.0 (4 reviews)

Google Rating: 5.0 (7 reviews)

Founded: 2017

Employees: 10-50

What makes them different?

Their expertise in high-performing Klaviyo campaigns is driven by two major factors: gathering insights through AI-driven data and utilizing A/B testing to optimize email performance. Their broader service offerings make The Email Marketers comprehensive partners for retention marketing. 

10. Fuel Made

Fuel Made is an ecommerce marketing agency that helps Shopify brands grow through advanced Klaviyo email and SMS strategies. They focus on using data, design, and automation to build emails that connect with customers and drive sales.
Their team includes strategists, writers, designers, and developers who work together to spot the biggest growth opportunities and build custom plans around them. As a Klaviyo Professional Partner and Shopify Plus Partner, they’ve earned a reputation for delivering clear results in a space that often overpromises.

Clutch Rating: 5.0 (20 reviews)

Google Rating: – (0 reviews)

Founded: 2000

Employees: 10-25

What sets them apart?

What makes them different is how focused they are. They’ve been working only with Klaviyo since 2016, and their team is made up of senior-level experts in every area of email marketing. Clients often stay with them for years, thanks to their mix of smart strategy and strong creative work.
They also stand out for how closely they connect email with ecommerce. Their dual expertise in Klaviyo and Shopify means they can create smooth, integrated experiences that actually convert. Their reporting is straightforward, with real numbers tied to performance—like doubling campaign revenue or boosting welcome series order rates by over 100%.

Benefits of Hiring a Top Klaviyo Email Marketing Agency

If you hire a Klaviyo agency the right way, you’ll usually get the most out of one of the best platforms for keeping customers. Here are some things you can look forward to:

1. Real Klaviyo skills

The best agencies know a lot about Klaviyo. They can make automation flows that start when people do something, dynamic product blocks, and advanced segmentation that really work. They make sure that every message, from the welcome series to the post-purchase flow, has a reason for being there and that everything works.

2. Don’t hire someone (and save time)

It takes time to run email campaigns in-house, and if your team doesn’t know how to set up emails or look at the results of campaigns, things could get out of hand very quickly. You don’t have to hire a lot of people because a Klaviyo agency sends a whole team with the right skills. That means your team can focus on what they do best and not have to worry about other things.

3. Campaigns that use data that gets better over time

Klaviyo gives you a lot of information, but it doesn’t matter if you don’t know how to use it or look at it. A good agency keeps track of what works, runs A/B tests, and uses real data to change campaigns. They’re always working on new features and fixes to make sure you get the most out of every send.

4. Emails that are nice to look at and work

Agencies know how to write emails that sound like your brand and get people to open them. They write clear and convincing copy and make templates that work on all devices, but especially mobile ones. No matter what you’re selling—clothes, supplements, or software—the goal is always the same: make it easy for people to do what you want them to do.

5. Better delivery and healthier lists

Some of the technical things that good Klaviyo agencies do to make sure your emails reach the right people are domain authentication (SPF/DKIM), IP warming, and list segmentation. That helps you keep your reputation as a sender strong and stay in touch with people who want to hear from you for a long time.

6. A plan for the whole lifecycle, not just emails that go out once

The best agencies send more than one email. They take care of every step of the customer journey, from the first contact to the last purchase. Every message has a goal, like getting someone to buy something or getting them to talk to you again. The goal is to increase the value of each customer over time.

7. Connections between tools and channels

The right agency will make sure that Klaviyo works with all of your tools, like Shopify, Gorgias, Recharge, Reviews.io, SMS platforms, and more. Your customers will have a good time because your messages will be the same on all channels.

8. Help that can change and grow with you

Your email marketing plan should change as your business does. Agencies can help you quickly switch to SMS, start new product lines, or run seasonal campaigns. You don’t have to take your time or teach new people. They are ready for you now.

9. Plans that are smart and have a creative twist

There are both tried-and-true ways that work and new ideas that you might not have thought of. Dynamic bundles, gamified emails, and content that is made just for you are some of the ideas here. They keep things interesting while still working toward their goals.

10. A real partnership and clear reporting

Agencies that are good send updates often. They always make sure that their goals are in line with yours. You always know what’s going well and what to do next because you get regular check-ins and reports that are easy to read. In that way and many others, they join your team.

How to Decide Among the Best Klaviyo Email Marketing Agencies?

Before you call agencies, make sure you know what you want to fix. Do you need more repeat customers by using RFM segmentation? Better ways to get people to leave their carts? A strategy for the whole lifecycle?
The worst thing you can do is say “we need better email marketing” without going into detail. This causes expectations to be out of line and money to be wasted.

Here are the 6 steps to choosing:

1. Set Your Goals

Don’t just say “better ROI from Klaviyo.” Be more specific. Do you need help with email design, flow automation, SMS integration, Shopify sync, or behavioral segmentation? Agencies can better address your real problems when they have clear goals.

2. Do some research and make a list

Look at articles, case studies, and videos on Google and YouTube. Find agencies that work with businesses in your industry and of a similar size. To avoid call fatigue, make a list of no more than three to five agencies.

3. Check for Expertise

Anyone can say they know how to use Klaviyo, but making advanced browse abandonment flows with dynamic recommendations is not the same as making basic welcome series. Look for real flow performance metrics and data on how much money each flow makes. Look for reviews from clients on their website, Clutch, or LinkedIn. If they won’t give you specific examples of their work or references, that’s a bad sign.

4. Plan Calls

Real conversations show how they think. Instead of immediately pitching packages, good agencies ask about your customer lifecycle and business problems. If they spend more time talking about themselves than about your needs, move on.

5. Ask for proof

Ask for specific examples, like welcome series, win-back campaigns, VIP journeys, and results before and after. Have them talk about how they worked on real projects, what problems they found, which Klaviyo features they used, and why they made certain choices. Quality agencies are happy to talk′s about how they do things.

6. Look at the price and value

The lowest price isn’t always the best. Low quotes often hide costs or cut corners. The right agency should be able to find optimization opportunities like untapped segments or triggers that aren’t working well, which will help you avoid costly mistakes. Think about ROI: if an agency charges $5,000 more but brings in $50,000 more in sales, that’s a good deal.

You’re picking a strategic partner who should care about your growth as much as you do.

Final Thoughts

Working with a Klaviyo-focused agency can help ecommerce brands get more from their email marketing. But it’s not just about knowing the platform. You need a partner who understands strategy, knows how to create strong campaigns, and uses data to keep improving results.

The best agencies don’t stop at basic emails. They build advanced automations, use smart segmentation, and create personalized customer journeys that lead to real revenue. They also keep things transparent with clear reporting and results you can track.

Email marketing takes time to get right. So choose a team that’s in it for the long haul and ready to adjust as your business grows.

Frequently Asked Questions (FAQs)

1. What is the average cost of hiring a top Klaviyo email marketing agency?

Hiring a Klaviyo email marketing agency can cost anywhere from $500 to over $5,000 per month. It depends on what you need – simple email flows or a full strategy across your customer lifecycle. Agencies usually charge in one of three ways:

• a monthly retainer
• a cut of the revenue they help generate
• or a flat project fee.

If you’re just getting started, you can also expect to pay a one-time setup fee in the first month.

2. What questions can you ask before onboarding with your Klaviyo agency?

Don’t just ask the usual scoping questions. Get specific and dig deeper into their Klaviyo expertise. Here are some questions to ask:

Start with their credentials:

• Are you a Klaviyo Master Elite Partner?
• How many brands like mine have you worked with?
• Can you show real examples of Flows you’ve built?

Dig into the strategy:

• Which Klaviyo Flows do you recommend for my type of business – welcome series, browse abandonment, win-backs?
• How deep do you go with segmentation beyond just age or location?
• Do you actually use Klaviyo’s predictive analytics and Smart Sending, or do you mostly stick to the basics?

Get technical

• How will you set up a particular integration and keep my data in sync?
• Out of Klaviyo’s 350+ integrations, which ones do you actually use and why?
• What’s your track record with Klaviyo SMS, and do you know how to make it work alongside email?

Talk about measurement:

• How do you track revenue attribution inside Klaviyo?
• What’s your process for A/B testing Flows versus campaigns?
• And how often do you go back and tweak my automation triggers to improve results?

The right agency will never shy away from talking about Klaviyo’s features and how they’d use them for your brand. If they treat Klaviyo like any other email tool, it’s a red flag. Keep looking.