SEO Website Migration Checklist: Step-by-Step Guide

Website migration is one of the riskiest processes for SEO. Even a minor technical mistake can cost you 30–70% of organic traffic. This guide walks you through every stage — from pre-migration preparation to post-migration monitoring.

What is SEO migration and when do you need it

SEO migration is a controlled process of moving a website while preserving accumulated organic signals: rankings, link equity, and indexation. You need it when:

• Changing domain (e.g. old-site.com → new-site.com)
• Moving from HTTP to HTTPS
• Switching CMS (WordPress → Shopify, OpenCart → WooCommerce)
• Redesign that changes URL structure
• Merging or splitting websites
• Changing language structure or target region

The golden rule: any of these actions without SEO preparation guarantees a traffic drop.

Step 1. Collect baseline data (before migration starts)

Before changing anything — record the current state of your site. This is your benchmark for post-migration comparison.

What to collect:

1. Organic traffic — go to Google Analytics 4 → Acquisition → Organic Search. Save a report for the last 3 months.
2. Keyword rankings — export from Google Search Console the list of queries and positions (at least top-50 pages).
3. URL list — full site crawl via Screaming Frog or Sitebulb. Save all URLs with status 200.
4. Backlinks — export from Ahrefs or GSC the full list of external links with anchors and referring pages.
5. Technical metrics — Core Web Vitals, page speed (PageSpeed Insights), current robots.txt and sitemap.xml.

📋 Checklist:

• GA4 traffic report saved (PDF or spreadsheet)
• GSC ranking list exported
• CSV with all site URLs
• Backlinks list (Ahrefs / GSC)
• PageSpeed report screenshot or PDF

Step 2. Redirect map

Every old URL that had traffic or external links must receive a 301 redirect to the new relevant page. This is the most critical element of migration.

How to build a redirect map:

1. Open the CSV with old URLs (from Step 1).
2. For each URL, specify the corresponding new address.
3. If a page is being removed with no replacement — redirect to the nearest topical page or homepage.
4. Maintain the table in the format: old URL | new URL | status (301/410)

Rules:

• Only 301 (permanent) — not 302, not meta refresh.
• Avoid redirect chains: A→B→C should be A→C.
• Don’t redirect the entire site to the homepage — Google treats this as a soft 404.
• Pages that no longer exist with no replacement — return 410 Gone.

📋 Checklist:

• Redirect table complete for all pages with traffic
• No redirect chains
• 301s configured on the new server (or via .htaccess / nginx)
• Redirects verified via httpstatus.io or Screaming Frog

Step 3. Technical SEO audit of the new site

Before public launch, the new site must be technically ready. Check everything on a staging environment.

What to check:

1. robots.txt — confirm production does NOT have Disallow: /. This is the most common cause of losing indexation after migration.
2. Sitemap.xml — updated, contains new URLs, does not contain old ones. Submit to GSC → Sitemaps.
3. Canonical tags — every page points to itself. No incorrect canonicals pointing to the old domain.
4. Title and meta description — migrated or improved. No duplicates.
5. Hreflang — if multilingual: tags are correctly set for all languages and regions.
6. Speed and Core Web Vitals — check via PageSpeed Insights. LCP below 2.5s, CLS below 0.1, INP below 200ms.
7. HTTPS — certificate installed, all internal links use https://, no mixed content.
8. Structured data — Schema.org markup migrated and valid (check via Google Rich Results Test).

📋 Checklist:

• robots.txt allows indexation
• Sitemap updated and submitted to GSC
• Canonical tags without errors
• Title and meta description on every page
• Hreflang (if multilingual)
• Core Web Vitals within limits
• HTTPS without mixed content
• Structured data valid

Step 4. Content migration

Content is one of the main SEO signals. You cannot just copy it as-is — you need to verify all elements are preserved.

What to check for each important page:

1. Text content — fully migrated, nothing cut. Do not shorten texts during migration.
2. H1–H6 headings — hierarchy preserved, H1 exists and is unique.
3. Images — uploaded to the new server (not linked from the old one), alt texts preserved.
4. Internal links — updated to new URLs (not pointing to old domain or 404).
5. Publication date — preserved or updated correctly (do not set today’s date on old content).

📋 Checklist:

• All content migrated without loss
• H1 present on every page
• Image alt texts preserved
• Internal links point to new URLs
• Images hosted on the new server

Step 5. Launch and first 48 hours

The DNS switch moment is the most critical. Follow a clear action plan.

Launch sequence:

1. Lower DNS TTL to 300 seconds 24 hours before migration — so the switch happens fast.
2. Launch the new site during off-hours (night, weekend) — fewer users will be affected by downtime.
3. Immediately after switching — check site availability via downdetector or uptimerobot.
4. Run a crawl via Screaming Frog to detect 404s and redirect errors.
5. In GSC — submit key page URLs for indexation via URL Inspection.
6. Confirm that GA4 and GSC are receiving data (tracking not broken).

📋 Launch checklist:

• DNS TTL lowered in advance
• Launch during off-hours
• Site accessible after switch
• Crawl shows 0 critical errors
• GSC receiving data
• GA4 recording sessions

Step 6. Post-migration monitoring (30–90 days)

Even a perfect migration requires monitoring. Traffic may temporarily dip — that is normal. But you need to distinguish temporary turbulence from real problems.

What to monitor and when:

Normal traffic stabilization timelines:

• Small sites (up to 100 pages) — 2–4 weeks
• Medium sites (100–1,000 pages) — 4–8 weeks
• Large catalogs (1,000+ pages) — 2–4 months

If after 3 months traffic has not recovered to 80% of the previous level — look for a technical issue: most often incorrect canonicals or an incomplete redirect map.

Critical mistakes that destroy traffic after migration

1. robots.txt blocking production — the site drops out of the index entirely. Check immediately after launch.
2. Missing redirects — Google and Bing forget pages without 301s. Link equity is lost.
3. Canonical pointing to old domain — the new site will never rank if canonical points to the old one.
4. Lost content — even one important page without a redirect means losing its rankings permanently (without re-doing the work).
5. Changing URLs without redirects at the same time as a redesign — a double blow to SEO. Make changes in separate steps.
6. Removing structured data — losing rich snippets in search = CTR drop of 20–40%.

Tools for SEO migration

Summary: complete SEO migration checklist

Before migration:

• Baseline data collected (traffic, rankings, URLs, backlinks)
• Redirect map built
• Technical audit of new site on staging
• Content verified on all key pages

During migration:

• DNS TTL lowered
• Launch during off-hours
• Immediate availability check and crawl

After migration (30 days):

• Daily traffic monitoring
• 404 and indexation error checks
• Weekly ranking tracking
• Core Web Vitals analysis

Migration is not a one-time action — it is a process that requires planning and control. Following this checklist allows you to preserve 90–100% of organic traffic even through radical site changes.