Why do top brands partner with email marketing agencies, and what do they actually do? Here's what really happens behind the scenes.
Email marketing has stood the test of time. It’s still one of the most reliable ways for businesses to drive sales, engagement, and revenue. Whether you run an ecommerce brand, a professional services company, or work in B2B, email campaigns deliver the kind of ROI most marketing strategies can only dream about.
But effective email marketing is more than just sending a newsletter every now and then. To get real results, you need strategy, design, automation, segmentation, analytics, and optimisation all working together. That’s exactly where an email marketing agency, or better yet, a specialist Klaviyo agency, comes in.
An agency gives you a team of experts who live and breathe this stuff. They know how to pair creativity with data, how to build automation flows that actually convert, and how to use insights from metrics to keep improving performance. If you’ve ever wondered what working with one actually looks like (and why so many brands partner with them), here are five reasons it could be a game-changer for your business.
The first step any email marketing agency takes is understanding your business, your audience, and your goals. Every company is different, which means a one-size-fits-all approach simply doesn’t work. Agencies will spend time analysing data, reviewing your existing email campaigns, and mapping out strategies designed to improve effectiveness and deliver stronger results.
This process includes decisions around segmentation (who receives what), personalisation (how to make content feel relevant), and automation (sending the right message at the right time). With the right email marketing software, such as Klaviyo, agencies can create tailored email marketing campaigns that match the specific needs of your business and your customers.
Once a strategy is set, the focus shifts to creating campaigns. This is where an agency’s creative team comes in. They’ll design content, write effective copywriting, and build email designs that look professional across all devices (Not just a 15.6 inch laptop screen). At this point, it’s important to remind ourselves that the goal here is to drive conversions, not just making emails look good. Strong communication and engaging content help businesses build relationships with people while encouraging actions that ultimately boost sales.
Agencies often combine email marketing services with SMS marketing or social media support to create multi-channel strategies. This integrated approach helps businesses create consistency across platforms and ensures every campaign feels connected to the overall brand.
Expertise in Automation and Personalisation
One of the biggest advantages of working with an email marketing agency is their expertise in automation. Automated workflows (welcome series, abandoned cart campaigns, post-purchase follow-ups) are a powerful way to improve performance without adding extra manual tasks to your team. Combined with personalisation, such as inserting names, using purchase history, or tailoring recommendations, automation ensures customers receive relevant, timely emails that feel valuable rather than intrusive.
This type of approach improves deliverability, increases engagement rates, and drives conversions. It also saves businesses time and ensures consistency across every email campaign.
It’s not enough to send out emails and hope for the best, you need to know what’s working and what isn’t. Experienced agencies use analytics tools to track results across key metrics such as; open rates, click-through rates, conversions, and ROI. With this data, they can deliver insights into how campaigns perform and make recommendations for optimisation.
For clients, this means you’re not left guessing whether your emails are doing anything. You get a clear picture of effectiveness, along with practical advice on how to improve future projects. Agencies with a strong track record often show measurable results within the first few months of work.
In reality, a reliable email marketing agency doesn’t really care too much about flashy campaigns. Instead, it invests time in taking care of behind-the-scenes tasks that can make or break success. This includes maintaining your subscriber list, ensuring list hygiene, and protecting deliverability. After all, even the best-designed email campaigns are useless if they don’t land in inboxes.
By keeping lists clean, managing opt-ins properly, and setting up the right technical authentication (SPF, DKIM, DMARC), agencies help businesses maintain trust with both customers and email platforms. This careful management improves performance and protects the long-term value of your marketing services.
Naturally, cost is a big consideration for any business deciding whether to hire an email marketing agency. Pricing structures vary, some agencies charge per project, some by campaign, and others offer monthly retainers. What matters most is value.
A good agency should deliver results that outweigh the cost of their services by generating more revenue through higher conversions, stronger engagement, and better ROI. When you factor in the time saved for your internal team, the expertise provided, and the overall impact on your marketing strategy, the investment often pays for itself.
Email marketing doesn’t exist in isolation. The best agencies understand how email campaigns fit alongside other marketing services like SMS marketing, paid media, and content marketing. They’ll advise on strategies that align with your brand, ensure communication feels consistent, and make decisions that support long-term business goals.
This approach means you’re gaining a partner who understands your company, your audience, and the way marketing impacts your bottom line.
To put it simply, expertise. Agencies bring together people who are at the highest level of their craft. They know the tools, the platforms, the strategies, and the pitfalls. They know how to create campaigns that actually convert. And most importantly, they know how to use data, insights, and communication to turn email into one of your most effective marketing channels.
Whether you’re a small business running your first email campaigns or a larger company looking to scale, working with an agency gives you access to the kind of strategies, solutions, and track record that would take years to build in-house. From automation and segmentation to content and analytics, their services are designed to take the guesswork out of marketing and replace it with results.
At a time where marketing strategies are constantly evolving, and often, a lot of it feels like guesswork, email remains one of the most direct, cost-effective, and high-ROI channels available. With the right agency on your side, the sky is the limit. Get in touch with our experienced team here.
Our mission at Frosted is to turn one-time buyers into lifelong customers. Retention is at the heart of sustainable growth. We help brands build lasting relationships, maximize revenue, and reduce reliance on paid ads – because keeping customers should be just as important as acquiring them.
Frosted Limited,
157 Compton Street,
Manchester,
M34 5DH
