Jay Omanson
July 02, 2026
3 Min
Website migration SEO checklist work is what keeps a redesign or replatform from turning into a slow, painful drop in organic traffic. If your URLs change, your platform changes, or you consolidate content, Google has to re-crawl and re-evaluate what you publish. Your job is to make the move obvious: every important page should have a clear “new address,” and every page that stays should stay easy to find.
We plan migrations at 10 Pound Gorilla the same way we build websites: you start with strategy, you get precise with the technical details, and you QA like you mean it before launch. The checklist below is written for marketing and digital teams who need a clean process for URL mapping, redirects, and validation without getting buried in dev-only language.
Before anyone writes code, you want the team aligned on the migration type. A visual redesign with the same URLs is one level of risk. A replatform with new templates, new navigation, and new URL paths is a different animal.
Migration types you should name in writing so scope stays clear:
If you are moving into DotNetNuke (DNN) or WordPress, the platform choice matters, but it is rarely the reason rankings rise or fall. Planning and execution usually decide the outcome. This is why you treat a migration as an SEO event and a development event.
You cannot map what you cannot see. Start by crawling your current site and exporting your full URL list, then flag what is actually indexable. That export becomes your source of truth for redirect mapping and QA.
In the same prep window, capture a baseline. You are not doing this to make a pretty report. You are doing it so you can answer, clearly, “Did we protect performance?” Search Engine Land calls out planning as one of the main reasons migrations go sideways, and their site migration SEO checklist is a solid reference for what to document before you touch production.
Pre-migration baseline checklist (simple, measurable, and useful in week 3 after launch):
301 redirect mapping is the migration deliverable that protects your rankings the most. Treat it like a required spec that marketing and development both sign off on. If you build it early, you can still influence IA decisions, content consolidation choices, and page templates before they are locked in.
Marcel Digital makes the same point in their website migration checklist: the redirect map is not something you toss together the night before launch. It is the connective tissue between the old site and the new one.
What your redirect map should include at minimum:
Redirect mapping rules that save you headaches:
Good mapping can still fail if the redirect rules are messy. For permanent URL changes, you want server-side 301s. You also want to keep redirects direct and predictable. Google calls out redirect chains and extra hops as a real problem because they waste crawl budget and can weaken how signals pass to the new URL. Their guidance in site moves with URL changes is worth sharing with your dev team if you need a neutral reference.
Redirect QA targets you can hand to a developer and a marketer without translation:
If your migration is happening on an enterprise build, a membership-driven site, or anything with tricky routing, it is worth having a senior engineer review the redirect logic before launch. With 10 Pound Gorilla, you work directly with senior developers, so redirect rules are not an afterthought. If you want to see what that build-and-launch support looks like, visit our Web Development Services page.
Your SEO QA should run in staging and then again right after launch. You are checking three things: crawlers can access the site, redirects behave the way your map says they should, and high-performing pages did not lose the signals that helped them rank.
Pre-launch SEO QA checklist (run it in staging, then repeat on production):
One practical note: do not separate SEO decisions from Accessibility and compliance. Navigation changes, heading structure, form patterns, and color contrast affect real users first, and they also affect crawl and interpretation. If your migration includes design changes, our Web Accessibility page explains how we bake accessibility and compliance into launches so you reduce risk instead of moving it around.
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Launch day is not the finish line. It is the start of monitoring. Your goal is fast feedback and quick fixes while Google is actively crawling the new version.
On launch day, prioritize these tasks:
Post-launch monitoring checklist for weeks 1 to 4:
Some fluctuation is normal. What you do not want is a steady slide that lasts past week 4 to 6. When that happens, the usual causes are missed redirects, indexability blocks, incorrect canonicals, or internal links still pointing to old URLs.
Most migration issues are not mysterious. They come from a few predictable misses. If you are managing internal stakeholders, this section is also useful for setting expectations early. It helps people understand why URL mapping and QA are not “extra.” They are part of protecting revenue.
Common migration pitfalls:
If you want one quick UI check that catches a surprising number of relaunch problems, review color contrast early. Low contrast is common, easy to miss, and painful to fix late. Our Learning Lab article on low-contrast text and how to fix it gives you a straightforward way to spot it before you sign off on designs.
How long should you keep 301 redirects after a migration? Plan to keep 301 redirects long-term. If you need a minimum, keep them for at least a year so search engines, partners, and real users have time to update links, bookmarks, and cached URLs.
Should you redirect every old URL to the homepage? No. This is one of the fastest ways to lose intent and rankings. Redirect old pages to the closest relevant replacement. If content is retired and there is no meaningful substitute, handle it intentionally instead of forcing a homepage redirect.
What is the difference between a 301 and a 302 during a migration? A 301 signals a permanent move and is the standard for migrations. A 302 signals a temporary move. If your URL change is permanent, use a 301 so search engines can transfer signals to the new URL.
Do you still need an SEO launch checklist QA pass if URLs are not changing? Yes. Redesigns can change indexability, internal linking, canonicals, headings, and content depth even if the URL stays the same. A launch QA pass catches quiet issues before they show up as traffic loss.
What tools do you need for URL mapping, 301 redirect mapping, and QA? You need a crawl tool to export URLs, a spreadsheet to manage mapping, and a way to validate status codes at scale. The tool names matter less than having a repeatable process and a clear owner for validation.
The best migration is the one you barely notice in analytics. If you build your URL inventory early, treat 301 redirect mapping like a real requirement, and run a true SEO launch checklist QA pass in staging, you give Google and your users a clean path from the old site to the new one.
If you are planning a redesign or replatform and want a clear plan for URL mapping, redirect strategy, and launch validation, start with 10 Pound Gorilla’s contact page. You will talk with senior experts who can help you plan the migration, pressure-test the redirect map, and launch with a No Surprises approach.