Site redesign is a broad concept. You can change the design, "theme", and background, and add or remove any elements - what is called design in the main meaning of the word. Such a "cosmetic repair" will not have any direct negative consequences for the size of the audience. If we talk about redesign as a change in the structure and navigation of the site, then this can lead to a loss of position in the search results, SEO traffic, and customers, respectively. Let's consider the second option in more detail.

How likely is it to lose your ranking in the search results?
When making changes to the site structure (renaming pages, creating new subdomains or, conversely, eliminating them with the subsequent movement of pages to the main domain address, etc.), the redesigned pages will change their ranking in the search results towards a decrease or exclusion. This will happen even if the content remains the same, internal links are not broken, and there are no external links leading to the changed pages.
Search engine algorithms are now complex and unpredictable. It is quite likely that after a certain time, the search engine will return the changed pages to their previous place in the results, but no one can guarantee this.
The forecast worsens significantly if:
- the content has changed;
- Internal and external links have stopped working properly.
In this case, it is necessary to take drastic measures. And it is better to do this before the redesign.
SEO optimization
The changed content must be harmoniously integrated into the existing semantic structure of the site. Thus, repeated requests on different pages will lead to a drop in the ranking of all these pages.
What to do:
If the redesign affected the content aspect, the new content must be consistent with the previous one. Perhaps this will require more significant changes within the framework of search engine optimization.
Meta data
Title is extremely important for search engines. Description — to a lesser extent, but its presence is also desirable in the page code. All metadata must be preserved and carefully transferred to the destination.
What else to do:
It may make sense to analyze the formulation of Title for its obsolescence and non-compliance with modern requirements. The criteria for the effectiveness of this meta tag change over time. Redesign is a good opportunity to work on the Title addition, which will improve the position of the page in the search results.
It will be interesting: How to write Title correctly - current tips.
Redirects
The issue of creating redirects is relevant for pages that are linked to by external links. Since a third-party resource or directory refers to a specific page, moving or deleting it entails deactivating the link.
What to do:
- Create a redirect map.
- Set a 301 redirect to redirect search engines and users from the old page to the new one.
The problem of subdomains
A good tip is not to change the structure of the site at all. If this is not possible, then it should be borne in mind that subdomains (most often these are third-level domains, for example - poddomen.site.com) are separate units for search engines with their own history and authority. Thus, moving a page from the main domain address to a subdomain will cause it to lose its "weight".
What to do:
If the site structure did not initially allow for subdomains, then it is better not to create them, continuing to place content as before. In extreme cases, use a 301 redirect, as discussed above.
Internal linking
Linked articles carry more weight with search engines. In addition, linking makes the site more monolithic and connected, which is also important for search engines.
What to do:
When redesigning, you need to make sure that all the previous linking is in order, that the links do not lead to non-existent pages, and that the linked pages are open for indexing (index, follow).
Following the general rules of user-friendly design
The above-discussed technical aspects are important for maintaining positions in the results after the redesign. However, user attitudes are not influenced by SEO, metadata, or the presence or absence of a 301 redirect. The user should be comfortable on the site. Let's briefly list the basic rules of a correct user-friendly design:
- orientation towards the mobile user, the share of which is growing every year: the site should be optimized for viewing from a smartphone;
- The user should not be overloaded with information;
- Use accent colors to highlight functions and elements that are important to a person.
Useful material: 7 UX mistakes that all designers unwittingly make.
The decision redesign should be justified. You should not radically change the site without good reasons. If there are such reasons, then first you need to analyze the problem areas, paying special attention to external links, internal linking, and the compliance of new content with the SEO structure of the site.