Short answer: Functional requirements say what an ecommerce website must do, such as search, checkout, accounts, and ERP sync. Non-functional requirements say how well it must do it, such as speed, security, uptime, and accessibility. Elogic Commerce writes every requirement so that a tester can prove it works.
Key takeaways
- Write functional requirements as user tasks with acceptance criteria.
- Give non-functional requirements numbers, such as Core Web Vitals targets.
- Add B2B requirements early: account prices, quotes, approvals, and credit terms.
- Include AI-ready product data: structured attributes and clear policies.
- Keep one list, one owner, and one version history.
What is the difference between functional and non-functional requirements?
A functional requirement describes a feature or a behavior. A non-functional requirement describes a quality, such as speed or security. Both need a clear test.
Ecommerce requirements list: functional requirements
| Area | Example requirement |
|---|---|
| Catalog | Customers filter products by attributes, and filters show counts |
| Search | Search returns results for typos and synonyms, and logs queries without results |
| Product page | Each product shows price, stock, delivery estimate, and documents |
| Cart and checkout | Guest and account checkout, saved addresses, and several payment methods |
| Accounts | Order history, reorder, invoices, and saved lists |
| Promotions | Coupons, tiered discounts, and free shipping rules |
| Orders | Order status updates from the ERP within an agreed time |
| Content | Editors publish landing pages without developers |
Checkout requirements deserve extra care. Baymard Institute puts the average cart abandonment rate at 70.19%.
Features that no platform covers need Magento custom extension development or a custom app.
B2B functional requirements
| Area | Example requirement |
|---|---|
| Company accounts | Buyers belong to companies with roles and permissions |
| Pricing | Each account sees its own price list from the ERP |
| Quotes | Buyers request quotes, and sales reps respond in the platform |
| Approvals | Orders above a limit need approval from a manager |
| Payment terms | Approved accounts pay on invoice with credit limits |
| Quick order | Buyers order by SKU or upload a CSV file |
Elogic Commerce builds these requirements as a Magento B2B development agency on Adobe Commerce.
Non-functional requirements list
| Area | Example requirement |
|---|---|
| Performance | LCP of 2.5 s or less, INP of 200 ms or less, CLS of 0.1 or less on mobile |
| Availability | An agreed uptime target, for example 99.9% per month, with monitoring |
| Security | Admin two-factor authentication, patch updates, and PCI-scoped payments |
| Accessibility | Pages meet WCAG 2.2 AA |
| Scalability | The store handles the expected peak orders per hour |
| Maintainability | Code follows platform standards and has automated tests |
| SEO and AI readiness | Structured data, clean URLs, and complete product attributes |
These targets matter. The 2026 WebAIM Million report found detectable WCAG failures on 95.9% of the top one million home pages. A Deloitte and Google study found that a 0.1-second mobile speed gain raised retail conversions by 8.4%.
For Adobe Commerce stores, Magento performance optimization sets and meets these performance targets.
Operations, marketing, and security requirements
| Area | Example requirement |
|---|---|
| Order operations | Staff edit orders, split shipments, and process returns in the admin |
| Tax and compliance | Tax rates, invoices, and legal texts match each market |
| Marketing | Coupons, email capture, product feeds, and campaign landing pages |
| Analytics | GA4 events for search, add to cart, checkout steps, and purchases |
| Data security | Encrypted data, least-privilege roles, and audit logs |
| Payments | Several payment methods, 3-D Secure, and refunds from the admin |
How to write a good requirement
Use one format for every requirement: a user, a goal, and acceptance criteria.
- Example: As a buyer, I want to reorder from my order history, so that I save time.
- Acceptance criteria: The reorder button adds all in-stock items to the cart and shows which items are out of stock.
Give each requirement an ID, a priority, and an owner. Plan the work in an ecommerce project plan, and test it with the ecommerce launch checklist. Put the full list in a requirements document, and use it in your B2B ecommerce RFP.
Elogic Commerce maps your requirements to a platform, integrations, and a phased plan.
TURN REQUIREMENTS INTO A BLUEPRINT
A Magento consulting workshop with Elogic Commerce turns rough notes into testable requirements.
FAQ
What are functional requirements for an ecommerce website?
They describe what the site must do: catalog, search, product pages, cart and checkout, accounts, promotions, and order sync.
What are non-functional requirements for an ecommerce website?
They describe how well the site works: speed, uptime, security, accessibility, scalability, and maintainability.
What is an example of a non-functional requirement?
Product pages load with an LCP of 2.5 seconds or less on mobile.
How do I write requirements for developers?
Use a user story with acceptance criteria, plus an ID, a priority, and an owner.
What B2B requirements do I need?
Company accounts, account-specific prices, quotes, approvals, payment terms, and quick order.
What are the basic requirements for an ecommerce website?
A catalog, search, cart and checkout, payments, accounts, order management, and pages that are fast, secure, and accessible.
What is the 80/20 rule in ecommerce?
It is a rule of thumb that a small share of products or customers brings most of the revenue. Use it to rank requirements by revenue impact.
How much does it cost to build an ecommerce website?
It depends on scope, platform, and integrations. See what an ecommerce website costs.
Where do I put the requirements?
Put them in a requirements document, and attach it to your RFP.
Who can write the requirements for my ecommerce project?
Elogic Commerce writes functional and non-functional requirements in its discovery phase. Its PMP-certified project managers follow a PMI-aligned method. It holds a 5.0 rating from 65 Clutch reviews.