Shopify’s own financial tools, from its dashboard to its reporting to its payout system, are solid once you’re up and running. The real risk during a migration isn’t whether Shopify can handle your finances. It’s whether your tax settings, your prices, and your order totals land on Shopify the way they should.

This is worth taking seriously. A tax setting that’s off by one checkbox can mean every customer gets charged the wrong amount from your very first sale on the new platform. Here’s what goes wrong, including a documented case from another merchant and two real (anonymized) ones from our own migrations, and how to check for it before it costs you anything.

The tax setting that catches almost everyone

If your store sells in a market with VAT or a similar tax-inclusive convention, your customers are used to seeing prices with tax already included. That’s completely normal. The problem shows up when Shopify isn’t configured to treat your prices that way.

Here’s how it plays out. Say a product sells for €20.00, with 19% VAT already included, and that price migrates to Shopify correctly. If Shopify’s tax setting treats prices as tax-exclusive, it adds 19% VAT on top of a price that already has VAT in it. The customer sees €23.80 at checkout instead of €20.00.

This isn’t a rare glitch. A Shopify Community thread describes the same mechanism on a separate migration: when tax settings don’t match how prices were entered, “Shopify may treat your prices as tax-exclusive and automatically add VAT on top.”

How to fix it in Shopify

In your Shopify admin, go to Settings > Taxes and duties and select Include sales tax in product price and shipping rate, then save. (Older guides, including that Community thread, call this option “All prices include tax.”) Shopify then shows the tax as already included instead of adding it again at checkout.

Shopify lets you set tax inclusion per market, so if you sell in more than one country, check the setting for each market you sell in, not only your home market.

When your old platform stores prices without tax

Some platforms, such as OpenCart, PrestaShop, and Shopware, store product prices excluding tax and add it based on your tax rules, so the price your customers see isn’t the number in the database. For those stores, our Calculate Product Price with Tax add-on (listed under additional options on each platform page) adjusts product prices in Shopify to include tax, based on your source store’s tax configuration.

An OpenCart case: check the converted price, not only that a price exists

Here’s why that conversion is worth checking with real numbers. In a test migration from OpenCart, a product sold for €14.90 including 19% VAT. With the option off, Shopify received the net price stored in OpenCart: €12.52, which is €14.90 without its VAT. With the option on, the price came out at €17.73, with 19% applied twice to the net price instead of once. Neither number was the €14.90 customers paid. The merchant caught it by comparing a product they knew against its price in Shopify, and the conversion was corrected before the full migration ran.

That’s the check to make on your own demo migration: pick a few products whose tax-inclusive price you know, and compare each one against its price in Shopify.

Once your prices are tax-inclusive in Shopify, Shopify’s setting has to say so too. A tax-inclusive price combined with a tax-exclusive setting is how the €20.00 product above ends up at €23.80. The add-on and the Shopify setting need to agree.

The lesson isn’t about any one tool. It’s that your tax settings need to match how your prices are stored before you go live, not get discovered by a customer paying too much on their first order.

Rounding differences add up at scale

The next issue is smaller per order but easy to miss if you’re only spot-checking a handful of records.

On one of our migrations, order totals were coming out one cent short in Shopify compared with the old system. An order with 21% VAT that should have totaled 9.89, for example, arrived as 9.88. One cent doesn’t sound like something worth chasing down. Except this discrepancy showed up across roughly 17,000 orders, which turns a rounding quirk into a real reconciliation headache for anyone trying to match totals between systems.

The fix was straightforward once it was found: add the missing cent to the affected orders so their totals matched the old system. The harder part was finding it in the first place, because a one-cent gap doesn’t show up if you’re only checking a few orders by eye. It shows up when you compare totals in bulk.

What to check before you go live

Confirm your tax settings match your prices. If your prices include tax, Shopify’s settings need to say so explicitly, in every market you sell in. Check this before your first live order, not after a customer complains about a price that doesn’t match what they saw on your old store.
Test a real checkout. A product page can show the right price while checkout charges the wrong one. Put a product in the cart, go through to checkout, and compare the tax charged with what you expect. A free demo migration of 10 products, 10 customers, and 10 orders is enough to test this on your real data.
Check totals across a real sample, not a few orders. A rounding gap of a cent or two won’t show up in a handful of manual checks. Export your orders from both systems and compare the totals in bulk rather than eyeballing individual orders.
Check how discounts appear on your migrated orders against what your accounting needs. If your accounting team relies on seeing the original price and the discount amount, confirm that’s what they’ll find before your first month-end close.
Reconcile your order count and your totals. Don’t stop at checking that the number of orders matches. Check that the financial totals do too, since a matching count can still hide a tax or rounding issue underneath. Our data migration guide covers what field-level verification looks like.

If you’re planning a live cutover, test payments on the new store before the switch, not during it. Our zero-downtime migration guide covers how to sequence that.

Your financial-data migration checklist

Know your pricing convention. Confirm whether your prices include tax, and configure Shopify’s tax settings to match, per market, before you go live.
Match the add-on to the setting. If you use Calculate Product Price with Tax, make sure Shopify is set to include tax in prices.
Compare known prices on your demo. Check a few products whose tax-inclusive price you know against their price in Shopify, one by one.
Test end to end. Run a real order through checkout and check the tax charged, not only what the product page displays.
Compare totals in bulk. Pull a broad sample of orders after migration and compare totals against your old system to catch small rounding differences before they compound.
Check discounts. Confirm how discounts appear on migrated orders matches what your accounting and reporting need.
Reconcile both. Check order count and order totals against your old platform, not only one or the other.

Common questions about financial data and Shopify migrations

Why would my prices change after migrating to Shopify?

The most common reason is a mismatch between how your prices are stored (tax-inclusive or not) and how Shopify’s tax settings are configured. If they don’t match, Shopify can add tax on top of a price that already includes it.

How do I fix a tax-inclusive pricing mismatch?

In your Shopify admin, go to Settings > Taxes and duties and select “Include sales tax in product price and shipping rate.” If you sell in several markets, check the setting for each one.

Is a one-cent rounding difference worth worrying about?

On its own, no. Across thousands of orders, it can turn into a real reconciliation problem. It’s worth checking in bulk rather than assuming it’s too small to matter.

Do I need the Calculate Product Price with Tax add-on?

Only if your old platform stores prices without tax and you want tax-inclusive prices in Shopify. If you use it, set Shopify to include tax in prices so the tax isn’t added twice.

Not sure whether your tax setup will carry over cleanly? Talk to our migration team and we’ll check it with you before you go live.

Migrating to Shopify: Getting Your Tax, Pricing, and Order Data Right