Ecommerce agency selection: The ultimate guide to hiring the right partner for your fashion brand

Choosing an ecommerce agency is a strategic decision. With the proliferation of ecommerce agencies on the market and the considerable investment that goes into hiring one, deciding the most suitable partner isn’t that simple.

Karolina Matuszewska

20 minutes

Many brands fail to pick the right one because they use the wrong evaluation criteria. But what’s the winning recipe? Let’s dive in. 

A great ecommerce agency with an understanding of the industry, combined with the latest trends and technologies, empowers your brand to optimize your store’s user experience and boost your online store.

In this article, we'll cover the steps to prepare and run such a search, team up with a partner who gets your brand and helps you achieve goals and increase revenue.

"Working with an ecommerce agency is more of a partnership than consultancy. This relationship involves an ongoing process of optimization and system architecture, necessary to maintain the business and thrive over time."

Anton Johansson, CEO & founder of Grebban, the ecommerce design agency and Centra partner

Navigating the vast landscape of ecommerce agencies can be overwhelming. As a guide for you, we’ve outlined actionable steps and key criteria when considering your options for a fruitful partnership that drives your brand's online growth.

1. Your decision criteria

Before you start your research for the perfect agency, set clear criteria for what you are looking for. 

Your fashion brand’s goals

Talk with your brand’s stakeholders to gather all relevant information, demands, and preferences you’ll need to identify your goals. 

Define the areas you’d like to improve:

  • Monthly sales, upsells, cross-sells, etc. 

  • Brand awareness

  • Customer retention

  • Qualified traffic to your online store 

Or, maybe your goal is to enter a new market as part of a new product launch or a localization strategy. 

Next, decide on the expected scope of the project. Are you looking to:

This stage also involves setting the estimated timelines and budget. 

Knowing what you want, it’s easier to screen the agencies against your brand objectives. You can narrow down your search and save time on finding an agency with capabilities, technologies and resources to let you reach your goals. 

Your position in the portfolio

A good way to determine the level of attention, time, and resources you'll receive from an agency is to find out where you fit into their client roster. Each scenario, being a larger or smaller client, offers distinct advantages and drawbacks. For example, while being a major client affords the opportunity to spearhead innovation, it may limit the chances to learn from more influential clients. Conversely, as a smaller client, you may not get as much attention, or have access to the agency's most experienced staff members, in comparison to larger clients.

“One way to find the right agency for your re-platforming project is to determine whether you prefer a more streamlined, low-key production agency, or one that provides high attention and competence. For some brands at specific stages of their journey, working with a more cost-efficient web agency might be the sensible choice. However, for fast-growing, ambitious, or larger brands, it often makes sense to partner with a highly organized, professional agency that can provide both expertise and implementation.” 

Anton Johansson, CEO & founder of Grebban, the ecommerce design agency and Centra partner

2. The ecommerce agency's experience and expertise

Now, it’s time to check the agency’s scope of services, if it offers consulting services, development services, or both. 

A perfect fit would be an agency that worked successfully in an ecosystem similar to yours – it’s simpler for them to grasp your fashion brand’s unique requirements, ultimately to efficiently build, launch, and maintain an outstanding platform.

Here are some detailed points worth considering:

Expertise in relevant ecommerce platforms 

Find a partner experienced in delivering similar projects with the platform you’re on or want to migrate to. Let’s say you’re working with a headless platform. An agency with the know-how of this technology gives you insight into its capabilities, limitations, and how to maximize the platform’s potential – making adjustments and upgrades, and offering custom services tailored to your brands' needs. For example, if you’re going to switch from Magento to a headless platform, a company with experience in these migrations can handle such a project well.

Industry recognition and awards

Investigate the agency's reputation through online reviews, industry awards, and press coverage. Browse for achievements in design and innovation, and check platforms like for client testimonials and ratings. We’ll talk more on that subject later in the article. 

As the landscape of ecommerce technology and fashion trends shift rapidly, it is imperative that your agency remains abreast of these changes. Their competence in leveraging the latest technological innovations guarantees its ability to enhance existing features, apply crucial security patches, fix bugs, and adapt to API modifications.

Number of successful ecommerce projects 

The number of well-executed ecommerce projects can demonstrate competence and expertise, analytical skills, and commitment to delivering quality results. It also shows that an agency has enough talented people on board to carry out multiple projects. What’s more, a seasoned agency has likely faced numerous challenges and can present how they dealt with them or the lessons they learned from their mistakes.

Prioritizing performance

An aesthetically pleasing website with compelling content may not suffice if it delivers a sluggish and subpar user experience. For instance, a website that is not mobile-friendly or has a slow checkout process can be detrimental to your business. Even impeccably written code can falter if the underlying system setup is flawed or fails to integrate seamlessly with essential tools, like inventory management or ERP systems. To ensure optimal performance and speed, the agency needs to exhibit a comprehensive understanding of both front-end and back-end intricacies.

This goes to say that, when selecting an agency, focusing on the development side of things alone may lead you astray. Focus on the agency’s capacity to adjust to your brand's strategic plan and bring innovative ideas to the table. In the best case scenario, you want an agency that will work with you as a unified team that knows your brand inside out. 

 Questions to ask the agency: 

  • Can you give examples of how you have customized ecommerce solutions to fit the unique requirements of your clients?

  • Can you share references and feedback from past clients?

  • Do you have any previous customers with relevant business similarities to our replatforming project?

  • Can you give examples of how you have helped other clients increase their ecommerce sales and revenue, and what strategies you have used? 

"The perfect partner for your ecommerce department does not only deliver excellent technology implementation but a lot of knowledge and insights into the ecosystem. They can guide you to the best CRM, CMS, return platform or other vendors. It's never one platform. It's always a combination of possibilities in a system architecture." 

Anton Johansson, CEO & founder of Grebban, the ecommerce design agency and Centra partner

3. Pricing, payment structure, and contract terms

Open communication about pricing and contract terms promotes transparency and builds trust between your fashion brand and the ecommerce agency.

Understanding the pricing model and the cost factors associated with hiring an agency ensures that the agency's services correspond with your financial limitations and anticipated expenses. It means you plan your budget accordingly and stay confident that your financial commitment is manageable.

The following types of pricing models are most commonly used by agencies:

  1. Hourly rate – The most popular model. An agency charges clients based on the number of hours worked. It’s straightforward, simple, and convenient for bookkeeping. But it prioritizes time spent on a project over value delivered, and possibly leading to questions about work efficiency and the agency's interests aligning with your brand's.

  2. Project-based or fixed fee – An agency estimates a project's cost by calculating how many hours it'll take. This is multiplied by the hourly rate per employee (or the agency's hourly rate) to figure out where to begin the calculation. If you have a budget set and a timeline, this model may work well, but it may limit creative gains or the initial estimates might be inaccurate resulting in additional charges. 

  3. Value-based – The agency charges based on what it does for the client, not how many hours it put in. It is highly scalable. This type of model can motivate agencies to deliver high-quality results, but it might be hard to achieve since everyone's perception of value might be different.

  4. Performance-based – Compensation for the agency is based on achieving specific targets or KPIs. It involves sharing risk and reward based on measurable results and goals. When targets are met, it can motivate the agency, but it will also require a bigger investment. It’s scalable, but can also be very work-intensive. 

  5. Retainer-based – Payments are pre-negotiated and upfront, based on the number of deliverables or the timeframe. It's easy for clients to budget, while agencies have predictable income streams, plus scalability. Retainers are beneficial to your brand if you require ongoing, consistent service from their agency. 

  6. Custom/Hybrid – Some agencies mix up two or more models, depending on your brand’s requirements, project, or service.

Discuss with the agency other details related to pricing and contract, including:

  • Payment methods

  • Payment dates and schedules

  • Invoicing process

  • Termination or renegotiation provisions

  • Additional costs and fees

  • Deadlines

  • Scope of the project

Also, check how the contract sets the conditions of post-launch support, the costs of additional development, services, and procedures for building new features or other additional work. Consult with the agency about what factors can affect the cost of maintenance, support and handling critical issues.

Service level agreements (SLA)

A service level agreement (SLA) is a common practice among agencies. It clearly defines the expectations and responsibilities of both parties to avoid misunderstandings and disputes. The contract sets a framework for dealing with any unforeseen issues that may arise during the project, as well as ongoing support and maintenance. Discussing SLAs with a potential agency is always a good idea. 

For instance, an SLA can specify how quickly an agency will respond to technical issues, such as site downtime or troubles with performance. As a result, the agency is responsible for keeping the ecommerce platform up and running smoothly. 

What an SLA should cover: 

  • Clear service description – the project's scope, timeline, and deliverables.

  • Performance metrics – metrics like site load times, uptime, and customer support response times. This way, you can establish expectations and objectively evaluate the agency's efforts.

  • Support commitment – the kind of support and maintenance that will be provided, like phone support, communication channels, and response time. Is it available 24 hours a day, 7 days a week, or only during business hours?

  • Issue resolution – how issues will be dealt with and resolved during the project, including escalation processes and expected resolution times. 

  • Penalties and remedies – what happens if the agency doesn't meet the agreed-upon performance metrics, like service credits or other compensation. 

  • Review and revise – the SLA needs to be always up-to-date and reflect any changes to the project scope. This keeps both parties aligned.

Some relevant questions to ask the agency:

  • Can you give a breakdown of the project's costs, including any extra fees?

  • Is it possible to get a sample contract or outline of its terms, such as length and termination?

  • How do you handle scope changes? Do you document them?

  • What happens if the project exceeds its budget?

  • Does ongoing support cost extra after a project is done?

  • Can you tell us how you keep the project within budget and how you prevent cost overruns?

4. The ecommerce agency’s client portfolio, testimonials and reviews

Reviewing an ecommerce agency’s client portfolio, case studies and testimonials gives an insight into its work, the types of ecommerce projects it has completed, its wins, and tactics. Look for notable fashion brand projects and discuss them with the agency – what went wrong and how they overcame the bumps on the way. 

Moreover, getting in touch with the agency’s clients is a great way to hear first-hand about the project. You could learn about the agency’s customer service, and their ability to handle projects similar to yours in terms of scale, complexity, and industry demands. It uncovers the agency's strengths and weaknesses. Plus, use your business network to get unbiased testimonials from clients, not just those provided by the agency.

Research what methods and services affected the international growth of the agency’s clients, such as website optimization, localization, and cross-border logistics. Maybe you'll get some inspiration for your brand as well.

A few useful questions when asking for references: 

  • Can you tell me how well the agency understood your business needs?

  • Did the agency deliver projects on time and within budget?

  • What ongoing support did the agency do after the project was completed?

  • How satisfied are you with the outcome of the project?

  • How would you rate the agency’s communication?

5. The ecommerce agency’s structure and resources

Evaluate an agency's structure. Technical capabilities are fundamental since they involve process discipline and standards. Assess how the agency aligns different development resources to turn them into workflows and ready-to-launch products. 

However, the most suitable structure depends on your goals. For instance, you might have strategic thinking people in-house and want to hire a technical team to implement your vision – or your team has little experience and might need guidance. 

Here are some extra considerations: 

Project team size and availability

A key asset in the agency is the project team, which is also your primary contact as it takes care of the planning, execution, and management of your undertaking. The right team size is important – a small team, 3-9 members, is usually more agile and faster-acting, while larger teams are better suited for complex projects. In the ecommerce sector, many agencies are gaining clients and growing quickly. With a doubled staff, they handle more projects, which can put a strain on core staff. As you evaluate potential collaborators, verify they have enough resources to handle your project. 

On the other hand, agencies sometimes lack resources or specialized skills for certain projects. They outsource part of the work to external partners to keep deadlines and maintain quality. The agency can fill gaps through this approach, but it can cause friction. Outsourcing can lead to collaboration challenges and inconsistencies in the final product and delays because of differences in processes and culture. And it may be hard to hold people accountable for outsourced work when responsibility is blurred. To minimize risks, agencies need to communicate effectively and set expectations. 

Roles and responsibilities

Most typically, when working with an agency, you’d be assigned a technical problem-solving person, such as a team lead or senior developer. Apart from that, in a well-designed team, there are several roles, such as:

  • Product owner

  • Project manager 

  • Developers – front-end, back-end, and full-stack

  • Web analytics expert

  • SEO expert

  • UX/UI designers

  • Solution architects 

  • QA engineers

  • DevOps engineers

  • Marketers

To keep things running without a hitch, each member's role and responsibilities should be defined in detail.

Having cross-functional teams

An effective ecommerce agency requires cross-functional teams with a diverse skill set, including developers, designers, QA engineers, and project managers. This variety of skills allows for better problem-solving and innovation, ultimately benefiting your fashion brand.

Agile approach 

Agile methodologies, like Scrum or Kanban, emphasize flexibility, collaboration, and iterative progress. If the agency applies such an approach it makes teams more efficient, as they adapt quickly to changing requirements and get things done faster. 

Design team 

Undeniably design skills are critical, the question is whether you have it in-house or rely on an agency for them. Many clients prefer design and development services under one roof. If that’s what you’re after, review the portfolio, talk to the team, and look at their work. However, some agencies have impressive portfolios, but they could have hired an external designer or the one behind their best projects may no longer be with them.

Extra questions to ask the agency: 

  • What is your team's structure, and what are the roles and responsibilities?

  • Do you outsource any part of your projects?

  • How do you envision the team project structure for my project?

  • To prioritize workloads, how do you manage multiple projects at once?

  • How many new clients do you expect to onboard before growing your team?

  • How many projects do you typically assign to one team at a time?

6. The ecommerce agency’s ecommerce strategy and process

The agency’s strategy and process should cover defining clear and measurable goals for your brand. It outlines timelines and milestones, identifying metrics and KPIs for the project, and how they will be tracked and reported on. This lets the agency's clients make informed decisions and set the expectations of the development. 

“As a brand choosing an agency, it's essential to understand in detail how they conduct their discovery process. Ask who they will interview to gain an understanding of the customer and their product. Are they data-driven? How do they aim to meet both brand and customer objectives? Answering these questions will help you choose a partner who truly understands your business and can devise a strategy that's aligned with the brand’s objectives.”
Ed Bull, owner & director at Limesharp

Evaluating the agency's strategy also involves:

Problem-solving approach

Check if your agency has a structured, systematic process and strategy for handling and resolving issues. This approach goes beyond addressing technical glitches, it also considers strategic or operational challenges that could impact the project’s profitability. Being proactive, anticipating and preparing for likely obstacles lays a solid foundation for a smoother delivery.

A reliable agency always has a contingency plan. It may be essential to create backup plans, find alternative solutions, or allocate resources to address the issues. This allows you to minimize disruptions, delays and fix the problem without exceeding your budget. 

SEO and UX optimization capabilities

Achieving great user experience, visibility, and traffic all contribute to the success of your store. Work with an agency that can assist you in optimizing the platform to meet such goals. See if it has its own SEO and UX specialists that will handle that, and what expertise they have in those areas. You can ask for case studies or portfolios covering that. Also, find out what the process for making your platform SEO and UX-friendly will look like, if any audits, tests, etc. are part of it. 

Future planning

Consult the agency about the future development of your platform. It needs to be scalable for future growth and expansion – able to handle more traffic, transactions, product listings, etc. Talk to the partners about how it can design it to easily add new functionality, features, and third-party services in the future.

“If your brand has an in-house tech team or plans to have one, it’s best to communicate that to the agency at an early phase so the project can be planned as a joint effort – including the hybrid working model structure, alignment of tech stacks, etc.” Ed Bull, owner & director at Limesharp

Security and compliance with relevant regulations

Running an online store involves handling customer information. Since you’re responsible for that customer data, it’s crucial to verify if the agency you’re going to work with can keep the platform safe and in line with relevant regulations. Check if the agency runs regular security audits and has solid safeguards in place, for instance, secure socket layer (SSL) encryption and two-factor authentication.

Moreover, if you operate cross-border and process customer data, you must comply with privacy regulations, e.g. the General Data Protection Regulation (GDPR) in Europe, or the California Consumer Privacy Act (CCPA) in the USA. And in case your platform processes payments, it should adhere to the Payment Card Industry Data Security Standard (PCI DSS). Also, consider the Omnibus Directive, which specifies rules for displaying promotional prices. If a brand doesn't follow these regulations, it could face hefty fines and damage its reputation. See if the agency can help you with those things too.

The integration of third-party tools 

Most ecommerce platforms use third-party apps and services, which can cause technical problems. You can talk to the agency about its experience with handling those, for instance, when integrating platforms with enterprise resource planning (ERP), inventory management software, etc. This will also cast light on the agency's ability to deal with technical issues and find fixes and workarounds. 

Key questions to ask the partner:

  • In what ways do you use customer feedback and data analysis to make decisions about your ecommerce site?

  • Is there a timeline for your project's completion? What are the steps?

  • What metric do you use to track ecommerce project progress?

  • How can you help us grow our brand online after the platform launches?

7. Communication and collaboration approach

Effective communication with an agency paves the way for smooth cooperation and project delivery. It requires the following: 

  • Regular updates on the project

  • Clarity and transparency regarding goals, expectations and concerns

  • Answering questions, concerns, or feedback right away 

  • Convenient communication channels 

  • Having clear roles and responsibilities to avoid confusion and promote accountability

A few things to keep in mind in terms of cooperation and communication: 

Availability and accessibility of the project manager

The project manager oversees projects from start to finish, making sure that they are completed on time and on budget. They serve as the primary point of contact between your brand and the agency, acting as a bridge between the two to keep you posted and meet your demands. In addition, a dedicated project manager can provide professional advice, let you discuss your ideas with them, put them into action, or dismiss them if not relevant – find what works best for your brand.

Policy for regular progress updates

You can expect from an agency regular project status updates, which are outlined in a dedicated policy. The policy typically covers setting clear communication channels, the frequency, format, and content of updates, granting clients visibility into the project's status, highlights, and possible challenges. With this policy, the agency enables a collaborative and well-informed working relationship with your brand by fostering transparency and trust.

Access to customer service tools

Customer care activities, such as order management, complaint handling, and answering inquiries, involve specific tools. Ideally, an ecommerce agency uses modern, robust collaboration tools and channels, such as Slack or MS Teams for real-time customer communication. Additionally, HubSpot, Zendesk, Asana, and other customer service software for submitting tickets are nice-to-haves. All these instruments play a big role in improving efficiency, responsiveness, and overall customer satisfaction. 

Cultural fit

A less obvious, but important aspect of finding an ecommerce agency is choosing the one whose culture aligns with your brand's values and working style. This encourages open communication and leads to more productivity and a better outcome. Sharing a common vision and goals, getting along well with each other can let you advance your project, solve issues and conflicts faster. Then you can build trust and rapport between your brand and the agency. So, if the technical expertise and tools are in place, a cultural fit will be the icing on the cake.  

Additional questions to ask the agency:

  • Can you walk us through your project management process and how you handle more complex projects?

  • Will you present a detailed project plan and timeline for our ecommerce project?

  • How do you align all stakeholders on the project's goals and objectives?

  • What tools and software do you use to support communication and collaboration between teams?

  • What steps do you take to meet the milestones and keep the project on schedule?

“The most successful client-to-ecommerce agency relationships transcend the typical vendor-to-client setup. With thoughtful leadership from both parties, these relationships can evolve into true partnerships where everyone collaborates towards the best outcome. Some of our clients even invite us to their summer parties! The dynamic feels more like that of colleagues than of a vendor and client. Invest in relationships, and ensure leaders from both sides act to foster a sense of connection among teams.”

Anton Johansson, CEO & founder of Grebban, the ecommerce design agency and Centra partner

8. A QA process 

For your platform to run smoothly, a quality assurance (QA) process is a must. It lets you pinpoint and correct defects in the ecommerce platform that could lead to lost sales. 

If the agency runs proper tests, it can save time and money later on and keep your project within the deadline. The QA team’s competence will impact the credibility and long-term success of the relationship. 

While talking to an agency, ask them about their standard processes. Learn how it prioritizes issues, ensures compatibility and consistent performance across different browsers, devices, and operating systems. Inquire about such things as:

  • Types of testing they do, like functional, usability, performance, security, and accessibility

  • Handling and resolving technical issues during development and launch

  • The process for managing version control and documentation for a transparent and traceable QA process 

Finally, discuss how the agency involves your team in the QA process. 

9. The approach to post-launch support and maintenance

Once the site is live, it entails ongoing maintenance and support to function properly, keep it up-to-date,  and meet the expectations of your customers. Here again, the agency’s experience in those areas is necessary. 

Talk to the agency if there will be any changes in the team size, pricing, and KPIs regarding that support. Your project's size and complexity, and the technology used, will determine what kind of support you need.

Finally, make sure you know what exact customer support you can count on and what communication channels will be dedicated to this task. This will give you peace of mind that you won’t have to tackle every issue on your own. 

There are several factors to consider:

Technical availability and support

It will be necessary to have consistent technical availability and quick support if anything goes wrong. Assure that the agency gives technical support in case of any downtime or functional issues affecting the store. 

Maintenance, security and updates

Maintenance following go-live often involves adjustments, to keep things running well and adding features to stay competitive. Ask the agency about a support plan, whether it covers regular backups, updates to software, and security checks. Also, find out how the agency addresses any technical issues or bugs that arise after the site goes live.

What’s more, cyber threats and hacker attacks may affect online stores. Customer data is your responsibility, and you want a company that provides top security to that data. To safeguard your platform against threats, it must have secure infrastructure and regular software updates. 

Data analysis and reporting

Ecommerce agencies typically take care of data analysis and reporting to monitor clients’ online store performance, find room for improvements, and act on data. This entails gathering data from various sources, such as website analytics, customer relationship management (CRM) and social media platforms. This allows for uncovering trends, patterns, and insights that help shape the client's ecommerce strategy.

A good report will include metrics from website traffic, conversion rates, through average order value, customer lifetime value, to return on ad spend. It is worth discussing with an agency its reporting strategy, frequency of reports, and what tools it utilizes, etc. 

Site performance optimization

After the launch, the agency usually tracks and analyzes the website's performance metrics to spot improvement areas and implement the necessary changes. For example, the agency can regularly update and fine-tune server configurations, reduce bottlenecks, and refine the website's mobile responsiveness. Verify that the agency offers support for emerging technologies and web standards to maintain your platform speed and efficiency. 

SEO optimization

Getting to the top of search engine results is challenging, so assistance from the agency is paramount. Find out if the potential partner offers SEO services after go-live. This usually means keeping current with the latest algorithm changes and emerging trends in SEO to refine your keywords and optimize content letting your brand reach your target audience.

Some additional questions to ask the agency:

  • How does the post-launch team look? 

  • How will you handle emergencies or critical issues after the site launches?

  • When the site launches, how do we request support or maintenance?

  • What is the cost of post-launch support and maintenance?

  • What terms and conditions will be included in the contract for post-launch support?

“A key factor in the ongoing optimisation and maintenance of an ecommerce site is to retain the same delivery team as much as possible. Competence, engagement, and understanding are cultivated over time. Some agencies have a business model focused on new projects, while others prioritize optimizing existing clients over time – be sure to select the latter. Another crucial element is having an adequate budget. It's easier for an agency to keep resources allocated to you as a client if you invest enough work hours.”

Anton Johansson, CEO & founder of Grebban, the ecommerce design agency and Centra partner

Moving forward: Navigating the path to ecommerce growth with your chosen agency

Selecting an ecommerce agency for your fashion brand is a big step. Take your time to define your needs. Then, evaluate your potential collaborators, making sure they have the suitable tools and processes to keep your work on track and elevate your brand

Now, let’s say you’ve found the holy grail, focus on building a strong partnership with the agency. The winning formula is open communication, setting clear expectations, and promoting mutual trust and collaboration. It means being responsive, sharing feedback regularly, and respecting each other's expertise. With a long-term perspective in mind, nurturing this relationship will help to put your brand in the spotlight and win more customers. 

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