Hello there, e-commerce brand founder. Let's answer this question for you quickly so you can make the best email marketing (and thus, retention marketing) decision for your baby.
My name is Reema. I am the Founder of Retain - we are a retention marketing agency for DTC brands. We've been doing this since 2020 and have worked with over 300 clients. So we know what we're talking about.
The honest answer: it depends on what you need. But here's what you actually need to know before you talk to anyone.
Full-service email marketing agency retainers for DTC ecommerce brands typically run $1,500–$5,000 per month at the specialist level, scaling to $8,000–$12,000/month for larger brands or more complex programmes. One-time setup projects — building your core flows from scratch — generally fall between $2,000–$5,000 depending on the number of flows and your tech stack.
Any agency that charges less than that, you should run away from. Fast. And don't look back. Even if they offer to do free work - especially if they offer to do free work for a month or so.
At Retain Marketing, our clients are DTC ecommerce brands doing a minimum of $50,000/month in revenue. For brands at that level, our retainers start from $1,500/month and scale based on the scope of work.
What Does That Price Actually Buy You?
When you hire a specialist email agency, you're not paying for someone to press send. You're buying a full team — strategist, copywriter, designer, and Klaviyo technician — working on your account every month. For the price of one junior in-house hire, you get four specialists with cross-brand experience.
Here's what a proper retainer covers:
Full Klaviyo account management
All automated flows built, maintained, and refreshed
Weekly or bi-weekly campaign emails
List segmentation and health management
Deliverability monitoring
Monthly performance reporting tied to revenue
What Does It Cost If You Don't Hire One?
A well-run email programme should generate 25–35% of your total ecommerce revenue. If your store does $50,000/month and email is currently contributing 8%, you're losing roughly $8,500–$13,500 every single month in revenue that's already sitting on your list.
One of our UK clients, Jubilee Scents, came to us with a beautiful brand and a list they weren't fully utilising. No dramatic overhaul. No discounting strategy. Just consistent, well-designed emails sent to the right segments. The result: £50,000 in revenue in 90 days — a 34% increase in repeat purchases, with open rates consistently between 35–50%.
A US sneaker brand we work with saw 396% growth across automated email flows after we rebuilt their welcome series, abandoned cart, and browse abandonment flows and integrated SMS at the right touchpoints.
The agency fee paid for itself before the end of month one in both cases.
In-House vs. Agency: The Cost Comparison
Building an internal email team that can match agency-level output means hiring at minimum:
An email strategist: $55,000–$75,000/year
A dedicated Klaviyo designer: $45,000–$65,000/year
A copywriter: $40,000–$60,000/year
That's $140,000–$200,000 annually — before software, benefits, or management overhead. And you'd still be onboarding them for 2–3 months before seeing any results.
A specialist agency delivers results in weeks, not months, and brings experience across dozens of brands in your vertical.
Red Flags to Watch For When Comparing Prices
Cheap doesn't mean affordable. Agencies charging $300–$500/month are typically managing 30–50 clients per person, sending templated campaigns with no strategy, and reporting on vanity metrics like open rates rather than revenue. If an agency can't tell you what percentage of your revenue should be coming from email — and exactly how they'll get you there — keep looking.
The questions you should ask any agency before signing:
What does your onboarding look like in the first 30 days?
Who specifically will be working on my account?
Can you show me a case study from a brand in my category with real revenue numbers?
How do you report on performance — and is it tied to store revenue, not just email metrics?
Curious to See What Email Can Do for Your Revenue?
Retain Marketing works exclusively with DTC ecommerce brands doing $50k+/month. If that's you, book a 15-minute call here and we'll show you exactly where your email programme is leaking revenue and what it would take to fix it.
If your MRR is lower than $35000, then hire an agency for one-time automation setup (i.e, building welcome flows, abandoned cart, and post-purchase etc). This runs to a one-time cost of $2,000–$5,000.
