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eCommerce Migration Checklist

Replatforming fails in one specific way: the redirects. Everything else — theme, apps, data import — can be fixed after launch. A broken redirect map cannot, because by the time the rankings have gone the crawl that would have found the problem has already happened. Forty-two checks, with mapping first.

CHECKS

42 checks

TIME TO RUN

Across the whole project

LAST UPDATED

September 2026

LEVEL

Project lead with developer support

Rows of open cardboard boxes ready for packing

A migration is a redirect project with a website attached. Treat it the other way round and you will pay for it in organic revenue.

Capture the baseline first

You cannot prove a migration went well, or badly, without a record of what existed beforehand. Take it before anything changes.

Comparing a printed report against a laptop

This is the step most often skipped and the one you will want most. Six months after a migration, arguments about whether traffic fell are unresolvable without a pre-migration snapshot — and they will happen.

Save all of it somewhere that is not the old platform, because you are about to switch it off.

SECTION 01

7 checks

The redirect map

The only part of a migration that cannot be fixed comfortably after launch. Build this before the new site exists, not after.

Laptop showing a world map while planning localised store experiences

Every old URL maps to one new URL. Anything that cannot be mapped is a decision, not an oversight.

List every indexed URL, not just the ones in your sitemap

Search Console, analytics landing pages, your crawl and your backlink data. Sitemaps routinely miss pages that rank.

Map every old URL to a single most relevant new URL

One to one wherever possible. Where it genuinely does not exist any more, map to the closest category rather than the homepage.

Never bulk-redirect to the homepage

Search engines treat a homepage redirect for a deleted page as a soft 404, and you lose the signal entirely. It is the single most damaging migration shortcut.

Use 301, not 302, for everything permanent

A temporary redirect tells search engines to keep the old URL. On a migration that is exactly wrong.

Check for redirect chains and collapse them to a single hop

Old chains from previous site changes compound during a migration. Two hops is tolerable, four is not.

Test the full map on staging before go-live

Every single URL, automated. Sampling finds the rule that works and misses the exception that does not.

Keep the map, and keep the redirects, indefinitely

Removing them a year later undoes the migration. They cost nothing to retain.

SECTION 02

7 checks

Data and catalogue

What moves across, what silently does not, and what arrives subtly corrupted.

Export products, variants, images, categories, customers and orders before anything changes

Keep the raw export. Platform exports are not always repeatable once a migration tool has run.

Check product descriptions survived formatting conversion

HTML in descriptions is where migrations mangle content. Spot-check fifty products across different categories, not five.

Confirm variant structure, SKUs and barcodes imported intact

Variant mapping is the most common data corruption in a migration, and it is invisible until somebody orders the wrong size.

Verify stock levels and prices against the source system

Compare totals, not a sample. A currency or decimal handling difference will show up in the sum.

Migrate customer accounts, and plan the password reset communication

Passwords never transfer. Customers who cannot log in on day one will simply not buy, and will not tell you why.

Preserve order history where the platform allows it

Support cannot answer questions about orders it cannot see, and returns windows do not pause for your migration.

Migrate product reviews deliberately

Reviews are a conversion asset and a structured data signal. They are also the thing most frequently forgotten until after launch.

SECTION 03

7 checks

Preserving search visibility

Beyond the redirects: the signals that have to be recreated rather than transferred.

Recreate title tags and meta descriptions, do not accept platform defaults

Most migrations silently overwrite these with a template. It is a sitewide regression that nobody notices for weeks.

Rebuild structured data and test the rendered output

Product, Breadcrumb and Review markup all have to be reimplemented. Theme documentation is not evidence; test the live page.

Preserve heading structure on templates

Themes decide H1s. A theme that puts the logo in the H1 will quietly demote every page on the site.

Keep internal linking patterns, especially collection to collection

Internal links are a ranking signal that does not transfer with a redirect. Rebuild them deliberately.

Match or improve page speed on the templates that carry traffic

A migration that makes the site slower converts the SEO risk into a conversion loss as well.

Submit the new sitemap on launch day and keep the old one available briefly

It helps search engines discover the redirects faster, which shortens the recovery window.

Confirm robots.txt on the new platform does not block anything valuable

Defaults differ between platforms. This is a thirty-second check that occasionally saves a quarter.

SECTION 04

7 checks

Commercial and operational continuity

The systems around the store that assume the old platform still exists.

Reconnect every integration: ERP, 3PL, accounting, PIM, feeds

Each one is a separate project. List them early, because the one nobody remembered is always the one that stops orders shipping.

Rebuild product feeds and resubmit to Merchant Center and any marketplace

Product IDs frequently change during migration, which orphans your entire shopping history if the feed is not remapped.

Re-create every lifecycle email flow and test each trigger

Flows do not migrate. Abandoned checkout in particular has to be rebuilt and fired at least once as a test.

Confirm tax configuration matches the old platform exactly

Tax differences surface in the first week as either angry customers or an unpayable liability.

Check discount codes, gift cards and loyalty balances transferred

Gift card balances are a legal obligation. Losing them is both a customer disaster and an accounting one.

Plan for subscription customers separately if you have them

Payment tokens rarely transfer cleanly. Get this wrong and you churn your most valuable customers in one afternoon.

Tell customer support what is changing, before it changes

They will field the confusion. Give them the password-reset explanation and the order-history situation in writing.

SECTION 05

7 checks

Launch window

The forty-eight hours either side of the switch, where attention is worth more than planning.

Do not migrate during your peak trading period

Obvious, routinely ignored. If your quarter depends on November, migrate in February.

Remove the staging noindex before go-live, and confirm the live site is crawlable

The single most common migration failure. Check the rendered robots directive on the live domain, not the setting in the admin.

Confirm the staging environment is now blocked or taken down

A crawlable duplicate of your new site competing with itself is a self-inflicted penalty.

Run the full redirect test against the live domain immediately after switching

Staging tests prove the rules. Only the live test proves the server applies them.

Place a real order on the live store within minutes of launch

Payment, tax, shipping rate, confirmation email. All four, on a real card.

Watch server response codes and error rates for the first day

A spike in 404s or 500s is your earliest signal, and the cheapest moment to act on it.

Have a rollback decision agreed in advance, with a named decision-maker

Deciding whether to roll back at 2am, without a pre-agreed threshold, produces the wrong answer.

SECTION 06

7 checks

The ninety days after

Migrations dip. What matters is whether the dip recovers, and you only know that if somebody is watching the right numbers.

Expect a temporary dip in organic traffic and say so in advance

A well-executed migration usually dips for two to six weeks. Telling stakeholders beforehand turns a crisis into a forecast.

Monitor Search Console coverage weekly for excluded and error URLs

This is where redirect gaps surface. Weekly for three months, not once after a fortnight.

Recrawl the site monthly and compare against the pre-migration baseline

Missing pages, new redirect chains and orphaned products all appear here first.

Track your top 500 landing pages individually, not just sitewide totals

A sitewide figure can look stable while your best category page has disappeared entirely.

Compare conversion rate against the pre-migration baseline by device

Migrations frequently improve desktop and damage mobile. The blended number hides it.

Fix broken redirects within days, not at the next sprint

Recovery time is proportional to how long the wrong signal was live.

If traffic has not recovered in ninety days, stop waiting

At that point it is not settling, it is a problem. Audit the redirect map against the original crawl.

Six ways migrations lose revenue

Ranked roughly by how much damage each does.

Redirecting everything to the homepage

Treated as a soft 404, so the signal is lost entirely rather than transferred. It is the fastest way to undo years of accumulated rankings in one afternoon.

Mapping only the URLs in the sitemap

Sitemaps miss pages that rank — old blog posts, discontinued products with backlinks, legacy category paths. Use Search Console and your backlink data as well.

Leaving the staging noindex on the live site

Every platform has one. Weeks of confusion follow, and the recovery takes longer than the outage did.

Migrating before peak season

The dip is normal. Taking it in your highest-revenue quarter turns a manageable cost into a bad year.

Forgetting an integration

The feed, the 3PL, the accounting sync. Usually discovered when orders stop shipping rather than when the site stops working.

Not capturing a baseline

Without a pre-migration snapshot, nobody can prove whether it went well, and the argument about it will run for a year.

Kitchenary and its case study cover a related situation: the analysis that should happen before a platform decision, not after.

Where the risk actually sits

Not everything in a migration carries the same consequence. Spend your attention in this order.

Risk

What it covers

If you get it wrong

When to do it

Critical

Redirect map, staging noindex, live crawlability

Months of lost organic revenue, and a recovery that takes longer than the mistake did

Before build completes

High

Data integrity, integrations, subscriptions, gift cards

Orders that cannot ship, customers who cannot log in, balances you legally owe

Before go-live

Medium

Titles, structured data, headings, internal links

A gradual decline that is hard to attribute and easy to blame on the dip

First fortnight

Recoverable

Theme polish, app parity, design refinements

Nothing that cannot wait. These are the things teams spend launch week on instead

After launch

The pattern every difficult migration shares: attention went to the recoverable row and the critical row was sampled rather than tested.

Where to go from here

01

STILL DECIDING

Migration is expensive enough that the choice deserves more than a feature table. The comparisons set out where each platform actually differs.

02

MOVING TO SHOPIFY

Shopify has its own structural quirks — duplicate product paths, handles, tag pages. Run that checklist alongside this one.

03

ALREADY MIGRATED, TRAFFIC DOWN

Work through the technical checks against your pre-migration crawl. Most post-migration losses are redirect gaps rather than mysteries.

04

WANT IT CHECKED PROPERLY

Five working days. Cheapest before you switch, still worth it in the ninety days after.

Migration FAQs

What people ask before and after replatforming.

Some temporary movement is normal even when everything is done correctly — usually two to six weeks. Permanent loss is not normal, and when it happens the cause is almost always the redirect map rather than the platform.

For a mid-sized catalogue, eight to sixteen weeks from decision to launch, and the redirect mapping should start in the first fortnight rather than the last. Compressing the timeline nearly always compresses the mapping, which is the wrong thing to compress.

Only if you must. Keeping the existing URL structure removes the largest single risk. If the new platform forces a change, that is what the redirect map is for — but do not take the opportunity to redesign URLs at the same time.

Immediately after your peak, so you have the longest possible runway before the next one. For most retailers that means January to March.

Plan the migration explicitly. They are a conversion asset and a structured data signal, they rarely transfer automatically, and they are the item most often remembered after go-live.

Indefinitely. They cost nothing to retain and removing them a year later undoes the work. Treat the redirect map as permanent infrastructure.

After ninety days it is a problem rather than a settling period. Recrawl, compare against the pre-migration baseline, and check every top landing page individually. The gap is usually a redirect rule that matched a pattern but missed its exceptions.

Planning a replatform, or recovering from one?

The redirect map is worth a second pair of eyes before you switch, and worth auditing properly if traffic has not come back. Both are covered by the free audit.

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