Klaviyo Agency vs In-House: The Six Roles You’re Actually Replacing

For a growing D2C brand, choosing between a Klaviyo agency and an in-house marketing team is rarely a simple hiring decision. It involves people, software knowledge, campaign management, customer data, reporting, design, and the time required to keep all of those pieces working together.

Klaviyo can support email marketing, SMS, customer segmentation, automated flows, campaign reporting, and other retention activities. Yet the platform still requires people who know how to plan, build, test, monitor, and improve those activities.

That raises a practical question for ecommerce companies. If you hire a Klaviyo agency, which internal roles are you actually replacing?

The answer usually involves six different areas of work.

1. Email Marketing Specialist

The first role is the most obvious.

An email marketing specialist is responsible for planning campaigns, writing or coordinating copy, building emails, managing lists, creating segments, scheduling campaigns, and reviewing results.

A capable Klaviyo agency can handle much of this work as part of an ongoing engagement. Instead of hiring a full-time employee solely for email marketing, a brand gains access to people who already work with Klaviyo accounts and ecommerce marketing programs.

This can be particularly useful for brands that have enough customer data and product activity to require regular campaigns but do not yet need a full-time email specialist.

The agency may also manage:

• Promotional email campaigns
• Product announcements
• Customer newsletters
• Abandoned cart emails
• Post-purchase emails
• Welcome sequences
• Re-engagement campaigns
• Customer segmentation
• Email performance reporting

2. Klaviyo Automation Specialist

Email campaigns are only one part of the work.

Klaviyo automation requires someone who understands how customer actions can trigger different communications. A flow may begin when a customer joins a list, views a product, places an order, abandons a cart, or reaches another defined condition.

Managing these workflows requires more than setting up a few automated emails. Someone needs to review triggers, filters, timing, exclusions, conditional splits, and customer paths.

This is where a Klaviyo expert can save an internal team considerable time.

A Klaviyo agency can audit existing flows, identify gaps, build new automations, and monitor whether customers are entering the correct sequences.

For a D2C company, that may cover the responsibilities normally assigned to a marketing automation specialist.

3. CRM and Customer Segmentation Manager

Customer data becomes increasingly difficult to manage as an ecommerce business grows.

A small store may have only a few customer groups. A larger D2C brand can have first-time buyers, repeat customers, high-value customers, inactive subscribers, recent purchasers, product-specific buyers, and many other segments.

Klaviyo segmentation can help organize these audiences, but someone still has to decide which segments are useful and how they should be used.

A Klaviyo agency can help define customer segments based on purchasing behavior, engagement, product interests, order history, and other available information.

The agency may also review whether campaigns are reaching the right people.

For example, a customer who purchased a product yesterday may need a different message from someone who has not purchased in six months. Good segmentation makes those distinctions manageable.

This means an agency can take on part of the work usually handled by a CRM or lifecycle marketing manager.

4. Copywriter and Email Designer

Every email requires creative work.

Someone has to determine what the message should say, how the offer should be presented, which products should appear, and how the email should look across different devices.

An internal team may need separate people for copywriting and design. Smaller companies often expect one employee to manage both.

An experienced Klaviyo agency can combine these responsibilities within its campaign process.

That may include:

• Email copywriting
• Subject lines and preview text
• Email layouts
• Product blocks
• Calls to action
• Mobile-friendly formatting
• Promotional campaign design
• Automated flow content

This does not eliminate the need for brand direction from the client. Product Siddha, for example, can help a brand maintain consistency by ensuring campaigns reflect its products, customers, and existing communication style.

The agency provides the production capacity while the brand retains control over its identity.

5. Ecommerce Data and Analytics Specialist

Reporting is another role that is easy to underestimate.

Someone needs to examine campaign results and determine what the numbers actually mean. Open rates, clicks, conversions, revenue, unsubscribe rates, flow performance, and customer behavior can all provide useful information.

The challenge is that reporting without context can become a collection of numbers rather than a useful business tool.

A Klaviyo agency can review campaign and flow performance regularly and identify areas that deserve attention.

For example, an agency may discover that a particular automated flow generates strong revenue while several campaign types produce weak engagement. That finding can influence future campaign planning and customer segmentation.

An in-house analytics specialist could perform the same work. The question is whether the company has enough ongoing analytical work to justify a dedicated position.

6. Email Marketing Strategist

The sixth role is broader.

A marketing strategist looks at the entire email marketing program rather than an individual campaign.

This person considers questions such as:

• Which customer groups should receive regular communication?
• Which Klaviyo flows should be created or revised?
• How often should campaigns be sent?
• Which products deserve more attention?
• Where are customers dropping out of the buying journey?
• Which campaigns are contributing to sales?
• What should the email program focus on next quarter?

For an in-house team, this may be the responsibility of a senior lifecycle marketer or ecommerce marketing manager.

With a Klaviyo agency, strategic planning can be part of the relationship. The agency can combine campaign management, automation, segmentation, creative work, and reporting into a single program.

That can reduce the amount of coordination required between several separate employees.

The Real Comparison

The choice becomes clearer when the roles are placed side by side.

Function	In-House Approach	Klaviyo Agency
Email marketing	Dedicated employee	Agency specialist
Klaviyo automation	Internal specialist	Klaviyo automation team
Customer segmentation	CRM or marketing employee	Agency strategist or specialist
Copy and design	Internal creative team	Agency creative resources
Analytics	Marketing or data employee	Agency reporting team
Strategy	Marketing manager	Agency strategist
Hiring responsibility	Brand	Agency
Training responsibility	Brand	Usually handled by agency
Team capacity	Limited to internal staff	Access to multiple specialists

The right choice depends on the size of the brand, the volume of campaigns, the complexity of its customer data, and the amount of work required each month.

When an Agency Makes Sense

A Klaviyo agency can be a practical option when a D2C company needs several areas of expertise without hiring six separate specialists.

It may also suit businesses that already have Klaviyo but are not using its capabilities fully. An agency can review the existing account, clean up flows, improve segmentation, develop campaigns, and establish a regular reporting process.

An in-house team can make more sense when email marketing is a large part of the company’s daily operation and there is enough work to keep dedicated specialists occupied.

The decision should therefore be based on workload and business requirements rather than simply comparing an agency fee with one employee’s salary.

A Practical Decision

Before choosing between an in-house team and a Klaviyo agency, list the work your business actually needs.

Count the people currently responsible for campaign creation, automation, segmentation, design, copywriting, reporting, and strategy. Then consider how much management time is spent coordinating those responsibilities.

For some D2C brands, an agency provides a more efficient way to bring several skills together. For others, building an internal team may be the better long-term choice.

The important point is to compare the full range of responsibilities, rather than treating Klaviyo management as a single job.

For D2C brands considering outside support, Product Siddha can help assess the work involved in managing Klaviyo and determine which functions should remain internal and which can be handled by an experienced Klaviyo agency.