A clinic I work with is moving its website off the platform it was built on. New site, same web address. The new one had been built, checked and sitting ready for two weeks.
Then I ran one last comparison before we moved the address across, and found three pages that existed only on the old site. Not one of them was on the new build. Two days later and they would have gone dark.
Switching website platforms is mostly a boring job. This is the part that isn't.
The pages nobody remembers building
The three missing pages were a privacy policy, a terms page, and a short page explaining how to text the clinic.
Nobody put them in the plan because nobody remembered making them. They were added two weeks earlier, in a hurry, for one specific reason: the phone carrier that lets the clinic send appointment texts requires those pages to exist at exact addresses. The carrier checked them once, approved the account, and everyone moved on.
The new website was built from the design. Somebody looked at the old site, listed the pages, and rebuilt them. Those three were never part of the design conversation, so they never made the list.
Here is what makes this ugly. If we had moved the address, the clinic's website would have looked completely fine. Every page a customer visits would have loaded. The failure would have shown up somewhere else entirely — in text messages that quietly stopped sending, because the carrier re-checks those addresses and finds nothing there.
Why the old checklist misses them
When you rebuild a site, you naturally list the pages a customer walks through. Home, services, pricing, about, book now. That list is easy to make because you can walk it yourself.
The pages that go missing are the ones with a different audience:
- Pages a supplier or regulator checks — policies, terms, consent pages, opt-out instructions
- Pages only reachable by direct link — a form you paste into an email, a landing page from an ad
- Pages added under time pressure — the ones created to unblock something, then forgotten
None of these get visits. None of them show up when you click around your own site. All of them can break something that costs you money.
What actually finds them
Two things, and both are cheap.
Compare the full page lists, not your memory
Pull the complete list of addresses from the old site and the complete list from the new one, and put them side by side. Not from a document, not from what the person who built it recalls — from the sites themselves.
One note from doing this: the site's own index of its pages is often out of date. On an earlier job I archived a site by trusting its index and got nineteen pages. Following every link on the site found sixteen more. A third of it would have been lost.
Ask what outside systems point at your site
Make a short list of anyone who holds one of your web addresses on file:
- Your phone or texting provider
- Your payment processor
- Google Business, ad platforms, directory listings
- Any form or booking tool that links back
Then check each address still works after the move. This is the step that would have caught our three pages in about four minutes.
Do it before the address moves, not after
The order matters more than the effort. Everything above is easy while both sites are still live — you can compare them, fix the gaps, and check your work.
The moment the web address points at the new site, the old one is gone from view and you are fixing things blind, while customers are already on the new pages.
We ported the three pages, swapped the personal mobile numbers for the business lines across every page, and swept all nineteen pages before touching the address. Nineteen out of nineteen came back correct. Then we moved it.
A page with no visitors can still be load-bearing. Before you switch platforms, find out who besides your customers is relying on your website — and check their pages first.