E-commerce Store Development — Complete Guide 2026

E-commerce store development is a multi-stage process aimed at building a functional, secure and mobile-friendly online sales platform. In 2026, the cost ranges from 1,500–2,800 PLN net for a simple store on a ready-made template, through 5,000–10,000 PLN gross for a custom design on an open-source platform, up to 15,000–50,000 PLN and more for a store with advanced integrations. The right choice depends on three things: your budget, the planned sales volume and the flexibility you need.

Najważniejsze: E-commerce store development in 2026 costs from 1,500 PLN net (ready-made template) through 5,000–10,000 PLN (custom design on WooCommerce or PrestaShop) to 15,000–50,000 PLN and more (a store with ERP and marketplace integrations). Delivery time ranges from 1–2 weeks (template) to 3–6 months (custom-built system).

How much does e-commerce store development cost? 2026 pricing

Store development costs vary depending on the vendor (freelancer or agency), the chosen platform and the complexity of the graphic design. The table below summarises approximate budgets for the most common delivery scenarios.

What drives the cost of an online store?

• Product count and variants — a catalogue of 100 products is a different challenge than 10,000 SKUs with variants, stock levels and multiple price lists. Large catalogues require efficient search, imports and synchronisation.
• Third-party integrations — every integration (payments, carriers, ERP, marketplaces, accounting) means hours of development and testing. This is the most common source of hidden costs in e-commerce projects.
• Graphic design — a ready-made template is the cheapest option, but a custom design adds 2,000–5,000 PLN and extends the project by 1–2 weeks. In return, it builds brand and trust.
• Custom features — product configurators, a B2B store with individual price lists, multilingual versions, subscriptions or loyalty programmes all require custom code.
• Data and content migration — moving products, customers and orders from an old system can cost more than building new store features.
• SEO and content — category descriptions, product pages, URL structure and structured data are work whose absence only becomes visible after launch, in search results.
• Post-launch maintenance — updates, security fixes, monitoring and development are ongoing monthly costs that should be planned at the quoting stage.

E-commerce store development stages

A well-designed store is not a template with products uploaded to it — it is a carefully planned sales process. Below are six stages whose omission usually comes back to bite after launch.

1. Analysis and sales strategy

It starts with a workshop where we answer key questions — what exactly are we selling, to whom, through which channels and how do we differ from the competition. The output is a product map, defined target groups, a list of required integrations and an initial budget. This stage determines the platform choice, so skipping it is the most expensive mistake in the entire project.

2. UX/UI design and information architecture

We design the category structure, filters, search and the purchase path — from the product page through the cart to checkout. Over 60% of e-commerce traffic comes from mobile devices, so we design mobile-first: large buttons, short forms, minimum clicks to payment. Mockups and a design system are created at this stage.

3. Platform and technical architecture choice

Based on the analysis, we choose the platform — SaaS, open source or a custom-built solution — along with the architecture: hosting, database, CDN and scaling strategy. A good decision at this stage means lower maintenance costs and easier growth. A bad one means rewriting the store from scratch a year later.

4. Implementation and integrations

This is the longest stage — deploying the template or custom design, configuring payment gateways, shipping integrations, the invoicing system and synchronisation with ERP or marketplaces. Every integration should have error handling, a job queue and monitoring — so that a failure of one system does not stop sales.

5. Testing, performance and legal compliance

Before launch we test the purchase path on different devices, verify payments in test mode, measure Core Web Vitals and check compliance with GDPR, the Omnibus Directive and accessibility requirements. A store with a slow cart or a payment error loses customers within seconds.

6. Launch, SEO and growth

After launch the work is not over — conversion optimisation begins. We set up GA4 analytics, product feeds for Google Merchant Center, monitor rankings and grow the store with new features. An online store is a product, not a project with an end date.

Which store model should you choose? SaaS, open source or custom-built

The three delivery models differ in cost, control and flexibility. The table below helps you decide at the start.

SaaS platforms — fast start without a technical team

Subscription solutions such as Shoper, Sky-Shop or Shopify provide fast deployment and low initial costs — running costs from around 50 to 300 PLN per month. You do not have to worry about hosting, updates or security, because the vendor handles them. The price of this comfort is concrete, though: you cannot modify the source code, you have limited control over performance and you depend on the platform's pricing policy.

Open source — full ownership and no sales commission

Popular systems like WordPress with the WooCommerce plugin, PrestaShop or OpenCart give you full ownership of the store and no commission on transactions. You pay for hosting and any developer support, and you can freely extend the store. The catch is responsible maintenance — neglected plugins are the most common cause of WordPress store hacks. Choose this model if you want to control long-term costs and plan to develop features.

Custom-built systems — when non-standard processes are the norm

Custom e-commerce systems built from scratch make sense when no off-the-shelf platform supports your business model — B2B quotations, product configurators, specific order workflows or integrations unavailable in plugins. They are the most flexible, but implementation can cost anywhere from tens to hundreds of thousands of PLN, and maintenance requires a dedicated team or technology partner.

Elements you cannot skip in an e-commerce project

A functional store is an ecosystem of dependencies — payments, shipping, inventory systems and legal requirements must work together. Here is the list of elements that determine whether a store earns money or generates problems.

Payment gateways — no sales without them

• Payment providers — PayU, Tpay, Autopay, Przelewy24 and Stripe cover the needs of most stores. Commissions typically range from 0.3% to 2.9% of the transaction value plus a fixed fee.
• Payment methods — a bank transfer alone is not enough. Customers expect BLIK, cards, Apple Pay and Google Pay. For higher baskets it is worth adding buy-now-pay-later options (PayPo, Klarna).
• After-sales handling — refunds, complaints, chargebacks and automatic payment reconciliation. A well-designed integration saves your accounting team hours every month.

Shipping integrations — label and tracking automation

• Carriers and parcel lockers — InPost, DHL, DPD, GLS and Poczta Polska. Parcel lockers are a standard in Poland that no store can afford to miss.
• Shipping aggregators — Furgonetka and Apaczka let you generate labels for multiple carriers from one panel, without integrating each API separately.
• Process automation — labels generated automatically after payment, tracking statuses sent to the customer, cash-on-delivery and returns handling. That saves 10–20 minutes per order compared to manual processing.

ERP, suppliers and marketplaces — consistent data across channels

• ERP synchronisation — Subiekt, Comarch ERP Optima or WF-Mag must exchange stock levels and prices with the store in real time. Manually rewriting data is a direct route to customer complaints.
• Marketplaces and omnichannel — Baselinker, Allegro, Amazon, Empik and eMAG. Selling across multiple channels without central synchronisation ends up selling products you do not have in stock.
• Accounting and invoices — integration with Fakturownia, iFirma or your accounting system eliminates manual document issuing and speeds up shipping.

I write more about designing resilient integrations in the articles Designing resilient API and webhook integrations and How to prepare a requirements brief for your web app project, and the concrete results of an implementation are described in the omnichannel integration case study.

GDPR, Omnibus and accessibility — obligations that are easy to miss

• GDPR — privacy policy, cookie consents, secure processing of customer data, data processing agreements with subcontractors and a record of processing activities. Gaps in this documentation risk fines reaching millions of euros.
• Omnibus Directive — for every price reduction you must show the lowest price from the 30 days before the promotion. The cart and product pages must be designed to present this information automatically.
• Digital accessibility (EAA) — since 28 June 2025, online stores in the EU are covered by the European Accessibility Act. In practice this means meeting WCAG 2.1 AA requirements: contrast, keyboard navigation, alternative text for images and readable forms.
• Terms of service and the right of withdrawal — clear return rules (14 days), delivery costs, a withdrawal form and e-receipts. Well-written terms protect you in disputes with customers.

E-commerce SEO from day one

• Category and URL structure — readable categories and URLs like /store/category/product, consistent with how customers type phrases into Google.
• Faceted filters — filters generate thousands of URL combinations that can flood Google with duplicates. Proper canonical rules and indexation control are among the most common technical mistakes in stores.
• Schema.org structured data — Product, Offer, AggregateRating, BreadcrumbList and FAQ let Google display prices, ratings and availability, boosting CTR before a user even enters the site.
• Core Web Vitals and mobile — loading speed affects rankings and conversion. Image compression (WebP, AVIF), caching and a CDN are the mandatory standard.
• Content and link building — category descriptions written for customers' buying intent and a product feed for Google Merchant Center.

Performance, security and hosting

• Hosting matched to scale — a store on shared hosting for 50 PLN per month will handle small traffic, but not an ad campaign. Plan performance before promotions, not during them.
• Security — SSL certificate, updates, backups, WAF and monitoring. If you process card payments on your own server, PCI DSS requirements apply — the simplest approach is to delegate payments to a provider (PayU, Stripe) that takes responsibility for card data.
• Load testing — before Black Friday it is worth checking how the store handles traffic several times higher than normal.

AI in an online store — what is worth implementing in 2026

• Product descriptions and translations — AI speeds up creating catalogue content, but requires human editing and attention to uniqueness so it does not hurt SEO.
• Semantic search and recommendations — language models understand buying intent better than classic keyword search, which translates into higher basket values.
• Chatbots and shopping assistants — they answer questions about delivery, returns and availability. Remember the obligation to label AI conversations (AI Act) and not to send customer data to public models without a legal basis.
• Inventory forecasting and fraud detection — AI analyses sales history and helps plan stock levels and catch suspicious transactions.

How much does it cost to run an online store?

Running costs are the second part of the budget that companies planning their first store forget about. Realistic monthly expenses look like this:

A small store will fit within 300–1,000 PLN per month plus commissions. A medium store with integrations, technical care and development costs 1,000–3,000 PLN per month. On top of that comes the marketing budget — without traffic, even the best-designed store will not sell.

Freelancer, agency or SaaS — how to choose a vendor

Each type of vendor has its place. A freelancer is the cheapest option for simple template deployments and reacts quickly to changes. An agency brings process, a design team, SEO and post-launch support, but pricing starts in the tens of thousands of PLN. A SaaS platform is the fastest route to selling, but you give up control over code and development.

Questions worth asking before signing a contract

• Does the deployment include technical SEO and structured data, or is that a paid extra?
• Who is responsible for updates, security and backups after launch?
• Will I receive the full source code and server access, or will I be locked in with the vendor?
• What does post-launch support look like — is there an SLA and how fast are fixes delivered?
• Will the store comply with GDPR, the Omnibus Directive and the EAA accessibility requirements?
• What are the costs of extending the store with further integrations, and who owns the data?

Store development checklist — 12 points to tick off

1. Assortment, target group and sales channels defined.
2. Platform matched to budget, scale and required flexibility.
3. Information architecture — categories, filters, search and the purchase path.
4. Purchase path tested on mobile devices.
5. Payment gateways configured with BLIK, cards and buy-now-pay-later options.
6. Automated shipping with labels and tracking.
7. Integrations with ERP, marketplaces and the accounting system.
8. Compliance with GDPR, the Omnibus Directive and WCAG 2.1 AA accessibility.
9. Technical SEO — schema.org, canonical, sitemap, product feed.
10. Performance — Core Web Vitals, image compression, caching and CDN.
11. Analytics — GA4, Google Search Console and Merchant Center.
12. A growth and maintenance plan for after launch.

Frequently asked questions

How much does e-commerce store development cost in 2026?

In 2026, e-commerce store development costs 1,500–2,800 PLN net for a ready-made template, 5,000–10,000 PLN gross for a custom design on an open-source platform and 15,000–50,000 PLN for a store with advanced integrations. Custom-built systems for large companies start at 50,000 PLN. The price depends on the number of integrations, the graphic design and custom features.

How long does it take to build an online store?

A simple store on a ready-made template can be launched in 1–2 weeks. A custom design on WooCommerce or PrestaShop takes 3–6 weeks, and an advanced store with ERP and marketplace integrations takes 1–3 months. A custom-built system takes 3–6 months, because it requires designing the architecture and processes from scratch.

Which platform is best for a small store?

For a small store, WooCommerce on WordPress is usually enough (lowest costs, full ownership, a large community), or a SaaS subscription such as Shoper or Sky-Shop (fast start, no technical team needed). PrestaShop works well for larger catalogues, and a custom-built system only makes sense for non-standard processes or large-scale sales.

Do online stores have to comply with Omnibus and the EAA?

Yes. The Omnibus Directive requires displaying the lowest price from the 30 days before a reduction, and since 28 June 2025 online stores are covered by the European Accessibility Act (EAA), which requires meeting WCAG 2.1 AA. On top of that come GDPR obligations — a privacy policy, cookie consents and secure processing of customer data.

Which integrations matter most in an online store?

The priorities are a payment gateway (PayU, Tpay, Autopay, Stripe or Przelewy24 with BLIK), a shipping integration (InPost, DHL, DPD via Furgonetka or Apaczka) and synchronisation of stock and orders with an ERP or marketplace through Baselinker. For many companies, integration with the accounting system and analytics tools such as GA4 is equally important.

How much does it cost to run an online store per month?

Running a small store usually costs 300–1,000 PLN per month — hosting (50–500 PLN), platform or integration subscriptions (50–500 PLN) and minor fixes. A medium store with integrations and technical care costs 1,000–3,000 PLN per month. Payment commissions are billed separately — usually 0.3–2.9% of the transaction value.

Freelancer or agency — who is better for building a store?

A freelancer is cheaper and faster for simple template deployments — around 5,000 PLN gross. An agency brings process, a design team and post-launch support, but pricing starts in the tens of thousands of PLN. Choose based on the portfolio of completed projects and ask about technical SEO, GDPR, performance and post-launch support terms.

Can AI help run an online store?

Yes — AI speeds up writing product descriptions, translations, customer service (chatbots), semantic search and product recommendations. Keep the obligations in mind — chatbots must be labelled as AI (AI Act), and customer data must be processed in line with GDPR, preferably without sending it to public models.

👉 Planning an online store? See how e-commerce store development works in my offer — from analysis, through implementation and integrations, to care and growth. Get in touch via the contact form or at kontakt@informatix.com.pl.

👉 Connecting your store to an ERP or marketplace? Check the e-commerce integrations service — Baselinker, Allegro, Amazon and accounting systems.

📖 See also: Designing resilient API and webhook integrations, How to prepare a requirements brief for your web app project and AI implementation cost.