A domain's nameservers decide which company's DNS the rest of the internet consults. Change them and every record for the domain, website, email and all the rest, is read from the new provider instead of the old one. Any record that exists only at the old provider stops working. So the safe order is always the same: copy every record to the new provider, check them, and only then change the nameservers.
Nameservers and DNS records are not the same thing
Think of the DNS records as entries in an address book: this name's website is here, its email goes there. The nameservers say which address book to use.
Editing a record changes one entry. Changing the nameservers swaps the entire book. If the new book is missing a page, nothing warns you; the internet simply stops finding whatever was on it.
What usually breaks
Email. If the MX records were not recreated at the new provider, incoming email has nowhere to go. Sending servers retry for a while and then give up, so the problem can take a day or two to show up as bounced messages.
Email reputation. If the SPF, DKIM and DMARC records were missed, email still sends but fails the checks receiving servers run. It starts landing in spam, and nobody connects that to a website change.
Verification records. Google Search Console, Microsoft 365 and many other services prove you own the domain with a TXT record. Lose it and the service may stop working or ask you to verify again.
Subdomains. Anything on its own name, such as a booking system at book.yourbusiness.co.uk or a shop at shop.yourbusiness.co.uk, has its own records. They are easy to forget because nobody thinks of them as part of "the website".
How long the change takes
Nameserver changes are slower to settle than ordinary record changes. The delegation for your domain is held by the registry for .uk or .com, and resolvers around the world are allowed to cache it for up to two days. Your own TTL settings cannot shorten that.
During that window, some visitors are reading your old DNS and some your new DNS. That is harmless if both hold the same records, and it is exactly why the new provider must be complete before the switch, and the old one left in place until the change has fully settled.
When changing nameservers is the right call
It is worth doing when you want your DNS somewhere with better tools or security, such as moving it to Cloudflare, or when you are consolidating a domain that has been spread across several providers.
It is often not necessary when only the website is moving. Some hosts ask for a nameserver change because it is easier for them, but most will accept an A record and a CNAME pointed at them instead. Editing two records leaves email completely untouched, which is why we prefer it for a straightforward website move.
The safe order
- Export or screenshot every record at the current DNS provider.
- Create the same records at the new provider. Some providers scan your domain and import records automatically; the scan cannot see everything, so check it against your export.
- Compare the two side by side, record by record, including email, verification and subdomains.
- Change the nameservers at the registrar.
- Leave the old DNS exactly as it is for at least a few days.
- Test the website on both the bare domain and www, and send and receive email from an outside address.