E-commerce is one of the most competitive spaces on the web. Your product might be excellent, your prices fair, and your shipping fast, but if your website's interface creates friction, shoppers will leave for a competitor who makes buying easier. User interface patterns are the building blocks of a smooth shopping experience, and choosing the right ones can have a direct, measurable impact on revenue. At Kosmoweb, we have built and optimized e-commerce sites for brands across the Czech Republic and beyond, and the five patterns below are the ones that consistently deliver the strongest results.
Before diving into specifics, it is worth noting that UI patterns are not one-size-fits-all. A pattern that works brilliantly for a fashion retailer with thousands of SKUs may be wrong for a specialty shop selling twenty artisan products. Context matters, and testing should always validate your choices. That said, these five patterns have proven their value across enough projects that we consider them essential starting points for any e-commerce design.
Sticky Navigation
Sticky navigation keeps your site's primary menu visible as users scroll down the page. In e-commerce, where product pages can be long and category pages even longer, losing access to the navigation forces users to scroll all the way back to the top to search, browse another category, or check their cart. That interruption breaks the shopping flow.
We implemented sticky navigation for a home furnishings retailer whose product pages included extensive descriptions, multiple image galleries, customer photos, and related product sections. The pages routinely exceeded ten screen heights on mobile. Before sticky navigation, users who scrolled deep into a product page and decided they wanted to compare another item had to scroll back to the top or use the browser's back button. Analytics showed a significant number of sessions ended during these scroll-back moments.
After adding a slim sticky header that included the logo, search bar, category menu, and cart icon, the average number of products viewed per session increased by 16%. The sticky bar also gave us a natural place to display a "Back to top" trigger and a persistent cart item count, both of which reinforced shopping momentum.
The key to effective sticky navigation is restraint. The sticky element should be compact enough that it does not consume too much screen real estate, especially on mobile. We typically reduce the header height by 30-40% when it transitions from static to sticky, hiding non-essential elements and keeping only the core navigation tools.
Infinite Scrolling
Infinite scrolling, or the progressive loading of content as users reach the bottom of the page, can be a powerful engagement tool for product listing pages. When implemented well, it eliminates the friction of clicking "Next page" and keeps users in a continuous browsing flow that mirrors the experience of scrolling through a social media feed.
However, infinite scrolling comes with important caveats. It can frustrate users who want to reach your site's footer (where contact info, policies, and other links live). It can make it difficult for users to bookmark or share a specific position in a product listing. And it can cause performance issues if hundreds of product cards load into the DOM without cleanup.
Our preferred approach is a hybrid model: load the first three pages automatically as the user scrolls, then show a "Load more" button. This gives users the seamless initial browsing experience while maintaining a sense of control. We also implement URL updates as new batches load, so the browser's back button returns users to their approximate position rather than sending them back to the top.
For a fashion e-commerce client with over 2,000 products per category, this hybrid approach increased average browse depth from 18 products (the first page) to 54 products per session. The "Load more" button gave users a natural pause point where many applied filters they had initially skipped, leading to more targeted browsing and a higher add-to-cart rate.
Personalized Recommendations
Product recommendations are not new, but the sophistication of recommendation engines has advanced considerably. Beyond the basic "customers who bought this also bought" approach, modern recommendation systems can factor in browsing history, time spent on specific product categories, seasonal trends, and even the user's geographic location.
The placement of recommendations matters as much as their relevance. We position recommendation blocks in three strategic locations: on product detail pages ("You might also like"), in the shopping cart ("Complete your order with"), and on the homepage for returning visitors ("Picked for you based on your recent visits"). Each placement serves a different purpose. Product page recommendations encourage exploration. Cart recommendations increase order value. Homepage recommendations bring returning users directly to relevant content.
For a Czech outdoor equipment retailer, we implemented a recommendation system that combined purchase history with regional weather data. When temperatures dropped in a user's area, the system surfaced cold-weather gear they had browsed but not purchased. This contextual relevance made the recommendations feel helpful rather than intrusive. The recommended product blocks generated 21% of the site's total revenue within the first quarter of implementation.
A word of caution: poorly calibrated recommendations can backfire. Showing a user products they have already purchased, or recommending items wildly outside their demonstrated interests, feels tone-deaf. Invest in the logic behind your recommendations, not just the UI that displays them.
Simplified Checkout Process
Checkout is where the most consequential drop-offs happen. A user has found a product, decided they want it, added it to their cart, and started the purchase process. Losing them at this stage means losing a nearly completed sale. Every unnecessary field, confusing label, or unexpected cost that appears during checkout is a potential exit point.
We follow a set of core principles for checkout design. Minimize the number of fields to the absolute essentials. Use address auto-completion to reduce typing. Show all costs, including shipping and taxes, before the user reaches the payment step. Offer guest checkout prominently, because forcing account creation at this stage is one of the most reliable ways to lose a sale. And provide multiple payment options, because a user who prefers PayPal but only sees credit card fields may abandon the purchase rather than fetch their wallet.
For a specialty food delivery service, we redesigned a checkout flow that had been built by developers without UX guidance. The original flow had a separate page for shipping address, a separate page for billing address (even though they were the same in 92% of orders), a page for delivery preferences, and a payment page. We consolidated it into a single scrollable page with smart sections that expanded and collapsed based on user input. The billing address section defaulted to "same as shipping" and only expanded if unchecked. Delivery preferences were presented as simple radio buttons rather than a dedicated page.
The streamlined checkout reduced average completion time from over four minutes to under two, and the overall checkout completion rate improved by 26%. The single-page approach also made it easier to implement real-time validation, so users caught errors immediately instead of discovering them after clicking "Next."
User Reviews and Ratings
Social proof is one of the most powerful drivers of e-commerce conversion. When shoppers can see that real people have purchased and enjoyed a product, their confidence in the purchase increases dramatically. Reviews and ratings serve as a trust signal that marketing copy alone cannot replicate.
The design of your review system affects its effectiveness. Star ratings should be visible at a glance, both on product listing pages and at the top of product detail pages. Review text should be easy to scan, with the option to filter by rating, sort by recency or helpfulness, and search for specific keywords. Including reviewer details like purchase verification, photos, and usage duration adds credibility.
We built a review system for a consumer electronics retailer that included structured pros and cons fields alongside free-text reviews. This format made individual reviews more useful and allowed us to aggregate common pros and cons into a summary block at the top of the review section. Shoppers could see at a glance that, for example, 78% of reviewers praised battery life while 15% mentioned that the device was heavier than expected. This structured summary reduced the time users spent reading individual reviews by about 30% while increasing their stated confidence in purchase decisions.
Encouraging reviews is equally important. A well-timed follow-up email sent seven to ten days after delivery, when the customer has had time to use the product, consistently generates the highest response rates in our experience. Including a direct link to the review form, pre-filled with the product name and order number, removes friction from the process. For the electronics retailer, this automated review request system increased the number of reviews submitted per month from roughly 45 to over 200, building a substantial library of social proof that benefited every subsequent shopper.
These five UI patterns, sticky navigation, smart scrolling, personalized recommendations, simplified checkout, and robust reviews, form a foundation that we at Kosmoweb return to on virtually every e-commerce project. They address the core challenges of online retail: keeping users engaged, helping them find what they want, building their confidence, and removing barriers to purchase. Implemented thoughtfully and tested rigorously, they are among the highest-return investments an e-commerce business can make in its user experience.