How to generate compliant invoices for marketplace sales

Registered, high-volume sellers can't treat invoicing as optional admin. Invoices are what your accountant, your tax authority and sometimes your buyers expect, and they have to be consistent — right company details, right numbering, right VAT treatment, every time. At a few sales a month that's a manual chore; at a few hundred it's a liability if it's done by hand.

The goal isn't to make invoices prettier. It's to make them generate themselves from data that already exists, so the document is correct because the sale was correct.

RestocksAIO builds each invoice from the confirmed sale: marketplace, SKU, size, payout and currency are pulled from the sale itself, not retyped. You generate either for a date range in Normal mode, or by loading a marketplace Sale History CSV when you need to invoice a specific batch — and it's batch generation, not one document at a time.

One invoice shape doesn't fit every situation, so the generator offers several and lets the site and your accounting needs decide. The main types: Summary merges all sales into a single invoice; SummaryByCashout produces one invoice per cashout (StockX and Alias); SummaryByVatRates splits sales into B2B and VAT (Alias); Individual writes one invoice per sale; and Simplified rolls everything into one summed line.

You also choose how the source data arrives. Normal generation works from a date range on the selected site; or you load a marketplace Sale History CSV — StockX, for instance, exports a VAT file — to invoice a precise batch; and a custom template covers anything bespoke, including StockX buyer invoices. One nuance worth flagging: Alias invoicing reads cashouts to derive the EUR rate, so a period without cashouts can't be invoiced in EUR (use Alias USD Only if you need USD). Picking the right type up front keeps a month's invoices consistent rather than a mix of shapes your accountant has to reconcile.

In practice the type follows the platform. For StockX and Alias, SummaryByCashout aligns each invoice to a cashout, which is usually what your accountant wants for reconciliation; Alias additionally offers SummaryByVatRates to split B2B from VAT sales in one run. For a clean monthly export where per-sale detail isn't needed, Summary or Simplified keep the document count low; where a buyer or platform expects one invoice per order, Individual delivers exactly that.

Whatever the type, the data behind it is the confirmed sale — marketplace, SKU, size, payout and currency pulled from the order rather than re-keyed. That's the whole reason batch generation is safe at volume: the documents are correct because the sales are correct, not because someone proofread a hundred templates. The discipline lives upstream, in confirming and tracking sales accurately; generation itself is the easy part.

A simple monthly rhythm keeps it painless: load and reconcile the period's paid sales, pick the type your accountant prefers, generate (with entry certificates riding along for qualifying B2B sales), push to your accounting tool, and archive the batch. The B2B platforms reward that cadence specifically — Alias and WeTheNew both expect invoices sent roughly monthly — so a fixed monthly run maps cleanly onto what the marketplaces ask for.

If you run more than one selling entity — or one entity across different VAT situations — business profiles keep them from bleeding into each other. Each profile holds its own company details, numbering and VAT mode, so an invoice always carries the right identity and the right tax treatment for the sale it covers.

Profiles also support invoice presets in several languages (English, Español, German, Polish), which matters when you're selling into multiple European markets and your documents need to read correctly for each buyer.

Two smaller settings save real friction at scale. The Creation Date sits on the Generate panel and defaults to today, but you can set a fresh date per run — useful when backdating invoices for a past period or aligning several batches to one accounting date, without editing a preset.

Invoice Presets are the language packs your documents print in: English, Español, German and Polish, which matters when you sell into several European markets and each buyer's invoice needs to read correctly. The three defaults can't be edited or deleted — pressing Edit Preset makes a copy — and each preset carries an invoice description box where you can drop standing text, such as the wording that marks an invoice as B2B. Set the language, the dates and the description once per profile, and every generated invoice inherits a consistent, correct presentation instead of being assembled by hand each time.

The costly invoicing mistakes are rarely the wrong total — they're a margin-scheme sale that produces a standard-VAT invoice, or numbers that don't match the entry certificate. VAT mode is set per profile and per controller, then flows through the rest of the stack so the same treatment applies everywhere.

Because the VAT mode lives on the profile, you set it once and every generated invoice inherits it. That consistency is worth more than any single document being perfect.

The Invoice Dialog only creates invoices for PAID sales, which is correct but introduces a classic trap: a sale that was still pending at quarter-end never gets invoiced unless you go back for it. Miss enough of those and your invoiced revenue quietly drifts from your real revenue.

There's a deliberate workflow to catch them. Generate across two quarters — the current one and the previous one — tick "Import old CSV to remove dupe", and import the prior quarter's CSV. The tool then surfaces only the sales that weren't on that earlier CSV, so previously-pending sales appear without duplicating anything you've already invoiced.

For intra-Community B2B supplies, the invoice isn't the only document the sale owes. German sellers shipping into another EU country need an entry certificate — the Gelangensbestätigung — to prove the goods crossed the border and qualify for VAT exemption under §17a UStDV. RestocksAIO generates it automatically alongside your invoices when you run generation for qualifying sales, such as StockX deliveries to its Netherlands authentication centre.

Because it's built from the same sales data as the invoice, its figures match by construction — supplier and customer VAT IDs, quantities, the place and month of entry, and an itemised attachment with order IDs, SKUs, sizes, delivery dates and tracking numbers. That's the whole argument for generating documents from sale data rather than rebuilding them: the invoice and the certificate that has to agree with it come out of one run, already consistent. The full treatment lives in the VAT guide in this cluster.

Generated invoices don't have to stay in the app. They push straight into LexOffice, SevDesk or Fakturownia, so the document that was generated from the sale lands in the tool your accountant actually works in — no re-export, no copy-paste.

To be clear about the boundary: RestocksAIO generates VAT-aware invoices and pushes them downstream; it doesn't file your VAT return. That stays with your accountant or accounting software. What you get is a clean, consistent invoice for every sale, sitting beside the entry certificates, labels and proof of delivery in the documentation suite.