What an ecommerce agency does
An ecommerce agency is an external team that makes sure an online store works and sells. Some only build the store; others cover the whole cycle, from platform to repeat purchase. Before asking for a quote, it helps to know which part you need.
- Platform: design, development, integrations and migrations on Shopify, PrestaShop, Adobe Commerce, VTEX or WooCommerce.
- Traffic: SEO, GEO to appear in AI assistants, and paid media on Google, Meta and other channels.
- Conversion: CRO, analytics and user experience.
- Retention: marketing automation, loyalty and apps.
- Marketplaces: Amazon, Miravia, El Corte Inglés and other channels.
- Content: product photography and video, social media.
What it costs and how it is billed
There is no single rate, because each service is billed differently. Three models are common in the industry, and they are often combined.
- Fixed-price project: to build or migrate the store. The price depends on the design, integrations and data to migrate.
- Monthly fee or bank of hours: for SEO, paid media, CRO, retention and ongoing development.
- Performance-based fee: part of the fee tied to sales or other agreed goals, common in paid media and marketplaces.
How to compare proposals
Compare scope, not figures. A cheaper proposal usually leaves something out: customer migration, an integration, training or post-launch support.
Also add what the agency doesn’t pay: the platform fee (for example, Shopify Plus starts at 2,300 dollars a month according to its official page), apps, payment fees and media spend. The useful figure is the total cost over three years against what you expect to sell.
How to choose an agency
These are the questions I would ask if I were on the other side of the table.
- Does it have case studies with client names and before-and-after figures?
- Who will work on my account, and how much experience do they have in my sector?
- How will we measure results, and how often will we review them together?
- Is it an official partner of the platforms it uses (Shopify, Klaviyo, Google, Meta)?
- Who owns the code, ad accounts and data if we end the relationship?
- What happens if results don’t come: what changes, and how soon?
One agency or several specialists
Working with one agency per area (development, SEO, paid, email) gives you specialists, but you have to coordinate them: when sales drop, each one looks at its own part. A full-service agency answers for the whole result, but it has to prove it is strong in every area, not just one.
At Webimpacto we chose the second option: more than 100 professionals across ecommerce, growth, retention, AI and content, with offices in Madrid, Barcelona, Seville, Elche and Pécs. You can see what we have done in our case studies.
Frequently asked questions
What is the difference between an ecommerce agency and a digital marketing agency?
A digital marketing agency works on acquisition. An ecommerce agency also works on the store itself: platform, catalogue, conversion, integrations and operations.
How much does an ecommerce agency cost per month?
It depends on the services and the size of the store. Ask for proposals with the same scope and compare them line by line, adding the platform, apps and media spend.
Is a local agency better?
For a store selling in Spain, it helps if the team works in your language and time zone and knows the market. Physical proximity matters less than experience with projects like yours.
We’ll tell you what we would do in your case, no strings attached. A real person from the team replies.
Founder and Chairman of Webimpacto. He drives the adoption of AI across the agency and its clients’ projects: GEO, agentic commerce and new channels such as ChatGPT Ads.