Site Move Redirect Mapping in London: The 2026 Agency Guide
25 August 2026
Learn how London agencies build 301 redirect maps for website moves. See costs, steps, and pitfalls to keep your SEO traffic intact.
What Is Redirect Mapping and Why It Matters for a Site Move in London
Redirect mapping is the process of matching every URL on your old website to a relevant URL on your new site, using 301 or 302 redirects. For London businesses moving between platforms — say, from Magento to Shopify or from a bloated WordPress site to a headless setup — this is the single most important step for preserving SEO equity. Without a proper redirect map, you lose rankings, PageRank, and traffic, and users hit frustrating 404s. Google treats each 301 as a permanent relocation, passing most authority to the new page. A cleverly built map prevents crawl errors and keeps the thousands of indexable URLs in your sitemap working for you. London agencies specialise in this because the local market is dense with e-commerce, publishers, and corporate sites where even a 5% traffic drop after a move can cost tens of thousands of pounds a month.
How a London Agency Builds a Redirect Map: Step-by-Step
A professional agency starts by crawling the entire live site with tools like Screaming Frog SEO Spider or Sitebulb. They pull a full list of URLs: product pages, category pages, blog posts, tags, images, and PDFs. Next, they log into Google Search Console and Bing Webmaster Tools to extract URLs that actually get clicks — these deserve the highest attention. The agency then maps each old URL to a new one, using exact matches where possible and regex or wildcard rules for pattern-based redirects, like /products/xyz to /shop/xyz. They prioritise revenue-generating pages and flag orphaned or low-value pages for removal. After building the map, they test it in a staging environment using a tool like Redirect Path, checking for redirect chains and loops. Finally, they implement it server-side via .htaccess, NGINX, or a plugin, and schedule a post-launch crawl to verify that every old URL resolves to a 200 or 301.
Typical Costs and Timelines for Redirect Mapping in London
In 2026, London agencies typically quote between £500 and £2,000 for a redirect map on a small site (up to 1,000 URLs). For a mid-sized e-commerce store with 5,000–20,000 URLs, expect £2,500 to £7,500, and for enterprise migrations with multiple domains, subdomains, and international targeting, costs range from £10,000 to £25,000+. The timeline depends on the size and the accuracy of your existing site inventory. Pure mapping takes one to two weeks for most sites, but a full site move — including staging, implementation, QA, and post-launch monitoring — typically spans four to eight weeks. London agencies may charge a premium over UK averages, but they often include technical SEO support before and after the migration, which saves you from costly traffic dips. Always ask for a fixed-price quote that includes a post-launch check at 2 and 6 weeks, because redirect issues often surface only after search engines re-crawl.
Common Redirect Mapping Mistakes London Agencies Fix
The most frequent mistake is mapping every old URL to the homepage. This spreads no authority and confuses users. Another is using 302 temporary redirects for what should be 301 permanent ones — a signal that can be ignored by search engines. Redirect chains are also common, where URL A points to B, and B points to C, forcing bots to follow multiple hops and losing link equity. Many site owners forget to update internal links, leaving visitors to bounce through redirects. A professional agency avoids these by using a crawl log analysis to identify which URLs bots actually access, reviewing server logs for legacy URLs, and implementing a flat redirect map with direct 301s. They also submit change-of-address tools in Search Console, update sitemaps, and monitor Google Search Console for coverage errors. Post-launch, they watch Analytics for sudden drops in organic traffic and use tools like ContentKing to spot redirect failures before Google does.
Choosing the Right London Agency for Your Site Migration
Not all SEO agencies handle redirect mapping well. Look for one with demonstrable experience migrating sites on your actual CMS — whether that's Shopify, Magento, WooCommerce, or a bespoke platform. Ask for case studies that show preserved or improved organic traffic after a migration, not just pretty mockups. Verify they use industry-standard tools like Screaming Frog, Ahrefs, and Google Search Console, and ask how they test before going live. A good London agency will walk you through a sample redirect map and explain its logic. Also consider their location; while most work is remote, having an agency in Shoreditch or Soho can be handy for face-to-face workshops. Check whether they offer post-launch support pro-actively — a site move is not done when the DNS points to the new server. Read reviews on Trustpilot or Google, and ask for references from London businesses that have done a site move in the past 12 months.
FAQ
For a typical London e-commerce site with 5,000 to 20,000 URLs, building a redirect map usually takes 5 to 10 working days. This includes the initial crawl, analyzing URL patterns, and creating the mapping in a spreadsheet. However, the full migration process, including implementing the redirects, testing them in staging, and monitoring post-launch, can take 4 to 8 weeks. Agencies often provide an interim solution and a final QA sweep to ensure no broken links remain.