A new website should be good news. Then three weeks after launch the phone goes quiet, and nobody can say why. What happens to your Google rankings when you redesign depends almost entirely on a handful of decisions made during the build, and most of them have nothing to do with design.
Google itself says you may see ranking fluctuations while it recrawls and reindexes a site after its URLs change, and that they settle down over time (sourced from Google Search Central). A wobble is normal. A lasting drop usually has a cause you can name.
The four ways a redesign quietly costs rankings
Addresses change without forwarding. Your old page at /furnace-repair becomes /services/heating. Without a permanent redirect, anyone using the old address hits a dead end, and so does Google. It's moving shop without leaving a note on the old door.
Pages get dropped because nobody checked what they ranked for. The menu gets trimmed from forty pages to twelve for a cleaner look. If one of the cut pages was quietly bringing in enquiries, they go with it.
Content gets thinned for a cleaner look. Detailed service descriptions become three-word headlines over a stock photo. It looks tidy, but there's less on the page for Google, or a customer, to understand.
The build's search block outlives the build. Developers often block search engines while a site is in development. If that block isn't removed at launch, the new site can't be crawled properly. Google's guidance specifically says to remove any noindex or robots.txt blocks that were only needed for the move.
What Google actually advises
Google's guidance for moves that change URLs is worth reading in full (sourced from Google Search Central). For a typical redesign, the points that matter most:
Map every old URL to its new one before launch, starting with your most important pages.
Use permanent redirects, and keep them for as long as possible, generally at least a year.
Update your internal links so they point straight at the new addresses rather than leaning on redirects.
Remove temporary noindex or robots.txt blocks that were only there for the build.
Don't reach for the Change of Address tool. It's only for moving from one domain or subdomain to another. A redesign on the same domain doesn't use it, so the redirects are doing all the work.
What to record before the build starts
This is the step almost everyone skips, and it's what turns "our traffic dropped" from an argument into a diagnosis. Before anyone touches the site:
Export your top pages from Search Console. In the Performance report, use the export button to download the pages that earn clicks, over the longest period on offer (sourced from Search Console Help).
Export your top searches the same way.
Save a full list of your current URLs, from your sitemap or a crawl.
Write down your current enquiry numbers. Calls, forms and bookings, by month. Rankings only matter because of these.
Save copies of your key pages, so you can compare what was on them with what replaced them.
If you'd like a quick health check of the current site before deciding how much to change, the $0 website audit is a good place to start.
Questions to ask whoever is building it
Which of our current URLs will change, and where will each one redirect?
How will the site be kept out of search during the build, and who removes that block at launch?
Which pages are being removed, and has anyone checked their search traffic first?
Who's watching Search Console for the first few weeks after launch?
If the answers are vague, the redesign probably needs more planning before it needs more design. And if you're still at the quote stage, I've broken down what a small business website costs in Canada, including what a proper build should cover.
When a rebuild is the right call, what our website work covers is written out too. Done carefully, a redesign doesn't have to cost you your rankings, though nobody can promise that none of them will move.
So before the first mockup, do you know which of your pages are bringing in the customers?