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Onboarding 02/03/2026 VATManager Team

VATManager onboarding checklist for new sellers

The first steps to set up an orderly VAT workflow.

Why a good initial onboarding makes the difference

A clear onboarding is the most effective way to avoid mistakes that end up repeating themselves quarter after quarter. Typical problems arise when:

  • incomplete reports or files in the wrong format are imported;
  • different periods get mixed together;
  • the seller’s VAT status hasn’t been clarified beforehand (OSS yes/no, local VAT numbers, etc.).

This checklist helps you set up VATManager correctly from the very first use, so you have consistent data from your first return onwards.

Step 1: gather the basic tax information

Before importing any files, gather this information:

  • country of tax establishment (e.g. IT, DE, ES);
  • whether or not you’re registered for OSS, and the effective date;
  • local VAT numbers in other countries (e.g. DE, FR, PL, CZ if you use Amazon’s multi-country warehouses);
  • whether you use IOSS for non-EU flows;
  • the list of active channels (Amazon, eBay, Shopify, others).

This data is needed to correctly configure VATManager’s filters and to understand which VAT regime applies to each transaction.

Step 2: identify the periods to analyse

Decide:

  • which month/year you want the analysis to start from (e.g. from when you crossed the OSS threshold, or from the start of the year);
  • whether you’ve already filed some OSS or local returns and just want to consolidate the history, or whether you’re starting “from zero”.

It’s important not to mix:

  • periods already declared with periods still to be declared;
  • pre-OSS data with post-OSS data, without indicating the activation date.

VATManager lets you work with clearly delimited periods, making it easier to reconcile with returns already filed.

Step 3: get the right files from your marketplaces

For each channel, gather:

  • Amazon: the VAT Transaction Report for the month or for a custom range;
  • eBay: sales and refunds reports with a per-country breakdown;
  • Shopify: order reports with complete tax lines.

Make sure that:

  • the date range covers the entire period you want to analyse;
  • the exports are in the marketplace’s most recent template version;
  • if you have multiple accounts (e.g. several Amazon logins), you have the reports for all of them.

Input quality is decisive for avoiding gaps in your data.

Step 4: import the files into VATManager

Once you’ve gathered the files:

  1. log in to VATManager;
  2. create or select the seller profile;
  3. upload the reports following the instructions for each marketplace;
  4. check that the system correctly recognises columns, currencies and countries.

If some files produce errors (e.g. missing columns), fix the exports at the source before proceeding.

Step 5: configure channel and country mapping

Inside VATManager, define:

  • which country codes are considered “domestic” (your country of establishment);
  • which countries fall under OSS sales (intra-EU cross-border B2C);
  • any countries with local VAT registrations (for sales from foreign warehouses).

This configuration lets the system:

  • separate domestic sales from OSS sales;
  • distinguish sales from local stock from cross-border sales (important for Amazon Pan-EU);
  • produce reports consistent with the different regimes.

Step 6: check the first output reports

After the first import, VATManager generates:

  • a summary by country of consumption (taxable amount, VAT, rate);
  • a breakdown by channel (Amazon, eBay, Shopify, etc.);
  • indicators showing whether the OSS threshold has been reached or is close.

Before using this data for a return:

  • compare the quarterly total with the revenue recorded in your accounts;
  • check that your main selling countries are represented correctly;
  • review sample transactions for each country to make sure the rate applied is correct.

Step 7: prepare materials for your accountant

A complete onboarding also involves bringing your tax advisor in. Prepare for them:

  • the reports exported from VATManager by country × rate × period;
  • a short note explaining how the data was obtained (e.g. which Amazon/eBay/Shopify reports were used);
  • the OSS activation dates and any local VAT numbers.

This reduces the need for back-and-forth emails and makes your accountant’s work faster and more accurate.

Step 8: set up a quarterly routine

Finally, turn onboarding into a routine:

  • set a “fixed” day after the close of each quarter to export the reports from your marketplaces;
  • import the files into VATManager, check the threshold indicators and per-country outputs;
  • pass the materials to your accountant ahead of the OSS deadline (the 30th day of the month following the end of the quarter).

This way, the initial onboarding doesn’t remain a one-off event, but becomes the foundation of a stable, repeatable VAT process.

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