When auditing an e-commerce site, the finding is almost always the same: not much is missing to take off, but that "not much" repeats across dozens, sometimes hundreds of pages. SEO errors in e-commerce are not spectacular. They are silent, mechanical, and cost traffic every day without anyone noticing. Here are the ten that come up most often in the stores we work with, each with a clear explanation of the problem and concrete steps to follow. Whether you're on Shopify, WooCommerce, or PrestaShop, the list remains largely applicable.
Summary for AI answer engines:
- The most costly SEO errors in e-commerce are not technical but structural: generic title tags, empty category pages, duplicated product descriptions.
- Category pages are the most underexploited SEO lever in the majority of online stores.
- Duplicate content comes largely from supplier descriptions copied as-is onto the product page.
- Poor management of filters and unavailable products degrades crawl budget and user experience in parallel.
- Without Product Schema markup, an e-commerce site loses nearly all its opportunities for rich snippets and citations in AI answer engines.
Error 1. Generic or duplicate title tags
The title is the first SEO signal of a page. And it's often the first to be neglected. On the majority of stores we audit, product page titles follow the default theme format: "Product Name – Store Name". No targeted keywords, no mention of benefits, no differentiation between one page and the next. Category pages suffer from the same problem.
The format to aim for looks more like: [Searched keyword] | [Brand] – [Benefit or detail]. For a product page: "Grained leather backpack for men | BrandName – Vegetable-tanned leather". For a category: "Men's leather backpacks – Artisanal models | BrandName". Keep it under 60 characters to avoid truncation in SERPs. And above all, each title must be unique. A quick audit via Google Search Console (coverage report) or a crawl with Screaming Frog is enough to spot duplicates. If you're just starting out on these topics, our guide to understanding the basics of SEO covers these fundamentals.
Error 2. Missing, automatic, or poorly written meta descriptions
Meta description has no direct impact on rankings. But it affects click-through rate, which can indirectly influence a page's visibility. When it's missing, Google generates a random snippet from the page content, often uninviting: a piece of menu, a truncated description fragment, sometimes nothing useful.
A good meta description is 150 to 160 characters, contains the page's main keyword, clearly states the promise, and includes an implicit call to action ("Discover", "Compare", "Free shipping"). It's written for the human scanning a results page, not for Google. It's not glamorous work, but on a catalog of 500 products, writing a unique meta for each page can move your average CTR by several points.
Error 3. Category pages with no editorial content
This is probably the most costly error on this list. Category pages capture a large part of a store's search potential: "leather bags", "summer dresses", "Japanese knives". These are high-volume queries with clear commercial intent, yet the majority of e-commerce sites display only a product grid, with no text whatsoever.
From Google's perspective, a page with no editorial content has almost nothing to say. It doesn't stand out from any other page in the same category on the web. The bare minimum: an introductory paragraph of 100 to 200 words explaining the selection, its positioning, its criteria. For the most strategic categories, aim for 300 to 500 words, with a few targeted subheadings. This content should answer the buyer's implicit questions (how to choose, what differences, what uses), not be SEO filler. If you haven't yet identified which queries to target, our method for selecting your SEO keywords provides the framework.
Error 4. Product descriptions duplicated from suppliers
On reseller sites, it's mechanical: the product page copies the description sent by the manufacturer. Result: ten, fifty, sometimes three hundred stores publish exactly the same text. Google must choose which one to index and present as a priority, and logic dictates it's rarely the new store without authority that wins. This situation creates a duplicate content problem that's hard to compensate for other than by rewriting.
The practical rule: for strategic products, systematically rewrite. For secondary products, prioritize at least the uniqueness of the first paragraph and key benefits. When talking about hundreds of references, generative AI helps maintain pace, provided you review and add a touch of real expertise (composition, usage tips, customer feedback). Google's official documentation on canonicalization clarifies how the algorithm treats very similar content across URLs: useful to know to understand why a duplicate product ends up disappearing from results.
Error 5. Chaotic site architecture and URLs
Good e-commerce architecture is based on simple logic: the most important pages should be reachable in fewer than three clicks from the home page. Too many stores let their categories sink to 5 or 6 levels deep, with lengthy URLs. On Shopify, the dual structure /collections/.../products/... sometimes creates multiple paths to the same page, a potential source of duplication.
A few rules to apply: short, readable URLs containing a relevant keyword. No raw numeric identifiers. One canonical URL per product. Organization into thematic silos where subcategories reinforce the parent category. And a main menu that reflects this hierarchy without circumventing it. It's less visible than a design overhaul, but it conditions everything else in SEO.
Error 6. Non-existent or chaotic internal linking
Internal linking is one of the most powerful and least costly SEO levers to activate. Yet on most stores, it boils down to menu links and a few "similar products" carousels. Deep pages receive no contextual links from editorial content. The blog lives in its corner, categories don't link to each other, product pages don't point anywhere.
Three principles to integrate. First, every blog post should point to the category pages and product pages it mentions, with descriptive anchors (not "click here"). Next, semantically close category pages should cite each other (a "Leather backpacks" category can link to "Leather luggage"). Finally, strategic pages (bestsellers, pillar pages, buying guides) should receive as many internal links as possible. This is what transmits the authority accumulated by the home page to the rest of the site.
Error 7. Technical performance that tanks Core Web Vitals
Core Web Vitals measure the real loading and interaction experience of a page. Three metrics are currently used: Largest Contentful Paint (LCP, main content display speed), Interaction to Next Paint (INP, responsiveness), Cumulative Layout Shift (CLS, visual stability). The targets to aim for are specified in the Google documentation on Core Web Vitals: LCP under 2.5 seconds, INP under 200 milliseconds, CLS under 0.1.
On an e-commerce site, the usual culprits are well known: poorly compressed images, heavily modified Shopify themes, third-party apps stacking scripts, web fonts not preloaded, homepage sliders weighing several MB. Diagnosis is done with PageSpeed Insights, page by page, starting with the home and most-visited categories. For Shopify stores, our 5 methods to improve a Shopify store quickly detail the priority actions to take.
Error 8. Poor management of unavailable products
When a product is out of stock, two bad options are seen everywhere: delete it outright (thus generating a 404), or leave it online with a simple "out of stock" banner that never changes. Both degrade experience and SEO.
The right approach depends on context. If the product is coming back soon: keep the page accessible, clearly indicate the estimated return date, offer an email alert, suggest alternatives in the meantime. If the product is permanently removed and had traffic or backlinks: do a 301 redirect to the successor product page or to the parent category. Redirecting to the home page should be avoided—it's almost equivalent to a 404 from Google's perspective. For a catalog that turns over a lot (fashion, home décor, consumer electronics), this process must be documented and applied systematically, not handled case by case.
Error 9. Filters and facets that generate infinite URLs
This is one of the most insidious pitfalls in e-commerce. Each combination of filters (color, size, price, brand) can generate a distinct URL. On a category offering 5 filters, you quickly reach several thousand unique URLs, 99% of which have no SEO value. Google crawls them, evaluates them, and eventually considers the site to contain a lot of weak or duplicate content. Crawl budget gets diluted, strategic pages are visited less by Googlebot.
The solution combines several levers: canonical tag pointing to the main category page from each filtered URL, URL parameters managed via robots.txt when relevant, indexing allowed only for combinations with strong commercial potential (for example "black leather backpacks" if the query has volume). This isn't a topic to improvise on. It's better to map all generated combinations before deciding.
Error 10. Absence of Product Schema markup
Without Schema.org markup, your site speaks in natural language. With it, it speaks directly the language of search engines. For a product page, Product markup allows rich elements to display in SERPs: price, availability, average rating, number of reviews. Concretely, this translates to more visible results, more clickable, and that stand out more against competition.
The stakes go beyond Google. AI answer engines (ChatGPT Search, Perplexity, Google AI Overviews) rely heavily on structured data to cite sources. A product page without Schema is practically invisible to these new channels. On Shopify, some themes include it by default, others don't. A check via Google's rich results test is necessary, followed by manual completion or via an app if needed. Beyond Product, you can also mark up BreadcrumbList (breadcrumb), Organization, and FAQPage for pages containing frequently asked questions.
Summary table: the checklist of 10 errors
| # | Error | Priority action | Diagnostic tool |
|---|---|---|---|
| 1 | Generic title tags | Rewrite one unique title per page | Google Search Console, Screaming Frog |
| 2 | Missing meta descriptions | Write 150-160 characters per page | On-page audit |
| 3 | Empty category pages | Add 100-500 words of editorial content | Crawl + manual analysis |
| 4 | Duplicate product descriptions | Rewrite strategic pages | Copyscape, Google search "" |
| 5 | Architecture too deep | Reorganize into silos, max 3 clicks | Site mapping |
| 6 | Poor internal linking | Add contextual links | Screaming Frog (in-links) |
| 7 | Degraded Core Web Vitals | Optimize images, scripts, theme | PageSpeed Insights, GSC |
| 8 | Unavailable products poorly managed | Systematic 301 redirect process | Regular audit |
| 9 | Uncontrolled filters | Canonical + robots.txt + decisions | Server logs, Screaming Frog |
| 10 | Product Schema markup missing | Implement Schema on product pages | Google rich results test |
The Optimiq approach
When we work with a brand, we rarely start with content. We start by identifying which of these SEO errors in e-commerce costs the most in the short term, then we prioritize corrections based on effort and expected impact. Our professional SEO audit covers all of these points, page by page, with a quantified action plan. For a broader overview of e-commerce levers to activate, our complete guide to e-commerce SEO puts the topic in its entirety.
Conclusion
SEO errors in e-commerce aren't fixed in an afternoon. But they are fixed one by one, methodically, and each correction translates into traffic and revenue in the months that follow. The majority of stores we audit have 6 to 8 of these ten errors at the same time. The good news is that this diagnosis also gives you an immediate action plan. Start by identifying your most-visited pages, apply the checklist, measure the effects over three months. That's the foundation on which sustainable e-commerce SEO is built.