Using Search Console to diagnose migration issues | Lillian Purge

Using Search Console to diagnose migration issues

Website migrations are one of those moments where everything you have built up in organic search is put under a microscope. In my opinion, no other activity exposes weaknesses in planning, communication, and technical understanding quite like a migration. When things go wrong, panic usually follows quickly, traffic drops, rankings wobble, and the first question I hear is almost always the same, what is Google doing.

From experience, the better question is what did we do, and that is where Google Search Console becomes invaluable.

I use Search Console on every migration I am involved in, not as a reporting afterthought, but as a diagnostic tool. It tells you what Google is seeing, what Google is ignoring, and where signals have broken down. If you know how to read it properly, it will show you exactly why a migration is struggling.

This article is a deep practical guide to using Search Console to diagnose migration issues. It is based on real migrations, real mistakes, and real recoveries. I will explain what I look at, why I look at it, and how I interpret the data, not in theory, but in practice.

Why Search Console matters more during migrations

In my opinion, Search Console is always useful, but during a migration it becomes mission critical. Analytics tells you what users are doing. Search Console tells you how Google is interpreting your site.

After a migration, the relationship between Google and your website is effectively reset. Google needs to crawl new URLs, reassess relevance, understand redirects, and rebuild confidence that the new structure represents the same entity as before.

From experience, when traffic drops after a migration, Analytics shows the symptom, but Search Console shows the cause.

If you do not know how to use it properly, you are essentially blind during the most sensitive phase of your site’s life.

When to start using Search Console in a migration

One of the biggest mistakes I see is waiting until after launch to check Search Console. In my opinion, that is far too late.

Search Console should be part of the migration process before launch, on launch day, and for months afterwards. Ideally, you should already be familiar with baseline data, so you know what normal looks like.

From experience, migrations that go badly often involve people logging into Search Console for the first time only after traffic has already dropped. At that point, everything looks alarming, and context is missing.

Knowing your pre migration baseline is essential, because diagnosis depends on comparison.

Setting expectations before you analyse anything

Before diving into reports, I always remind clients and teams of one thing, not every fluctuation is a problem.

In my opinion, some level of movement after a migration is normal. Google needs time to crawl redirects, consolidate signals, and reassess relevance. The key is distinguishing between expected volatility and genuine structural issues.

Search Console helps you make that distinction, but only if you approach it calmly and methodically.

The Pages report is your starting point

If there is one place I always start after a migration, it is the Pages section, previously known as the Coverage report.

From experience, this report immediately shows whether Google is able to crawl and index the new site properly. It highlights errors, warnings, excluded pages, and indexed pages in one place.

After a migration, I look at this report daily at first. I am not looking for perfection, but I am looking for patterns.

Diagnosing indexing drops after migration

One of the most common migration issues is a sudden drop in indexed pages. In Search Console, this shows up clearly as a decline in the number of indexed URLs.

From experience, this usually points to one of a few problems, blocked pages, incorrect canonical tags, redirect chains, or internal linking failures.

I always compare indexed page counts before and after migration. If the drop is significant and unplanned, something has gone wrong.

In my opinion, unintentional deindexing is one of the fastest ways to lose traffic after a migration.

Understanding excluded pages properly

The Excluded section is where many people panic unnecessarily. Not all excluded pages are bad.

From experience, I separate exclusions into expected and unexpected. Expected exclusions include redirected URLs, duplicates with canonical tags, and parameter variations.

Unexpected exclusions are where problems hide. Pages marked as Crawled currently not indexed, Discovered currently not indexed, or Duplicate without user selected canonical can indicate deeper issues.

In my opinion, these statuses often reveal content dilution, poor internal linking, or unclear page purpose introduced during migration.

Redirect validation through Search Console

Redirects are the backbone of any successful migration. While Search Console does not show redirect mappings directly, it reveals whether Google is processing them correctly.

From experience, I check old URLs in Search Console using the URL inspection tool. If Google recognises the redirect and shows the correct new canonical URL, that is a good sign.

If it does not, or if the redirect chain is complex, that often explains ranking losses.

In my opinion, redirect issues are rarely about missing redirects alone, they are about redirect quality and relevance.

Canonical errors and migration confusion

Canonical tags cause more migration issues than almost anything else, in my experience.

After a migration, I often see canonical tags pointing to old URLs, staging domains, or incorrect page versions. Search Console flags these inconsistencies clearly.

When Google ignores your declared canonical and chooses a different one, that is a red flag. It usually means Google does not trust your signals.

In my opinion, canonical confusion is a clear sign that the migration introduced mixed messages.

Using the Performance report to spot intent loss

Once I have a sense of indexing health, I move to the Performance report. This is where you can see how rankings, impressions, and clicks have changed.

I always compare pre and post migration periods. I look at total impressions first, not clicks. Impressions tell you whether Google still considers your site relevant.

From experience, if impressions drop sharply, relevance signals were damaged. If impressions stay stable but clicks drop, the issue is often titles, descriptions, or user trust.

Query level analysis after migration

One of the most powerful things you can do in Search Console is analyse performance by query.

After a migration, I look at high value queries that previously performed well. If those queries have lost impressions, it usually means the associated pages lost relevance or authority.

From experience, this often happens when content is rewritten or merged without understanding search intent.

In my opinion, losing intent alignment is one of the quietest but most damaging migration mistakes.

Page level performance tells deeper stories

I also analyse performance by page. This is where you can see which URLs have lost visibility.

From experience, pages that lost traffic often share characteristics, changed URL structures, reduced content depth, weaker internal links, or altered headings.

Search Console helps you connect those dots. It shows you where the decline is concentrated, not just that a decline exists.

Comparing old and new URLs effectively

During migrations, I often keep a mapping spreadsheet open while analysing Search Console.

I compare old URLs that ranked well with their new equivalents. If the new page is underperforming, I ask why.

From experience, the answer is rarely technical alone. It is usually a combination of content changes, link loss, and internal context.

Search Console does not fix this for you, but it gives you the evidence.

Crawl stats reveal hidden technical issues

The Crawl stats report is often overlooked, but during migrations it can be incredibly revealing.

I look for sudden drops in crawl requests or changes in response codes. If Google is crawling less, it may indicate reduced trust or accessibility issues.

From experience, hosting changes, server errors, or slow response times introduced during migration often show up here.

In my opinion, crawl behaviour reflects Google’s confidence in your site.

Mobile usability after migration

Mobile usability issues often spike after migrations, especially when templates change.

Search Console flags these clearly. From experience, even small usability problems can affect rankings if they impact a large number of pages.

I always check this report early, because mobile issues are often unintended side effects of redesigns.

Manual actions and security issues

While rare, I always check the Manual actions and Security issues sections after a migration.

From experience, poor SEO practices or inherited issues sometimes surface at this stage. It is better to rule these out early than assume traffic loss is algorithmic.

How long to monitor Search Console after migration

In my opinion, Search Console should be monitored closely for at least three months after a migration, and periodically for up to six months.

Recovery is not always immediate. Some issues take time to resolve as Google recrawls and reassesses.

From experience, migrations that recover well are those where issues are identified early and corrected quickly.

Using Search Console to guide recovery actions

Search Console is not just diagnostic, it informs recovery strategy.

If indexing is weak, focus on internal linking and crawl paths. If performance dropped for key queries, revisit content and intent. If exclusions are high, refine canonicals and page purpose.

In my opinion, recovery should always be data led, not reactive guesswork.

Common mistakes when using Search Console during migrations

One of the biggest mistakes I see is overreacting to daily fluctuations. Search Console data lags slightly and trends matter more than single day changes.

Another mistake is looking at only one report in isolation. From experience, migration diagnosis requires connecting multiple signals.

Search Console does not replace experience

I want to be clear, Search Console is powerful, but it does not replace understanding.

In my opinion, the tool gives you answers, but only if you know the right questions to ask. Migration diagnosis is about interpretation, not just data.

From experience, the best outcomes come when Search Console insights are combined with solid SEO fundamentals and calm decision making.

Final thoughts on using Search Console for migration diagnosis

Website migrations do not fail because Google is unpredictable. They fail because signals get disrupted.

Search Console is the clearest window into how those signals are interpreted. If you learn to use it properly, it turns panic into process and confusion into clarity.

In my opinion, every migration should have a Search Console monitoring plan baked in from day one. It is not optional. It is the difference between guessing and knowing.

If you are planning a migration or recovering from one, start with Search Console. It will tell you more than any ranking tracker ever will.