Practical operational guide for marketplaces

How to use the guide

This guide describes what a small or medium-sized marketplace owner needs to decide, build, show to users, and archive. It is not a code specification. It assumes the sale of physical goods to consumers in Poland, with the possibility of allowing sellers from other EU or non-EU countries.

First choose the business and responsibility model, then build the marketplace

The biggest mistake of a small marketplace is starting with a catalog, cart, and payments without determining who actually sells, accepts money, packs, imports, and handles complaints. These decisions change almost every subsequent obligation.

Construction plan: what must exist and when

Responsibility Matrix: Operator, Seller, and Suppliers

Seller Onboarding: Whom to Allow to Sell

Onboarding cannot be a single survey of 'company/private person'. It must establish roles, upon which consumer law, product safety, BDO, VAT, DAC7, and payouts depend.

Product card: information without which an offer cannot be published

The product card is not solely marketing material. It is the place for fulfilling pre-contractual obligations, GPSR, DSA, and industry-specific regulations. The absence of a mandatory element must result in blocking publication, not a yellow warning that the seller can ignore.

GPSR: Product Safety in Practice

The General Product Safety Regulation (GPSR) applies from 13 December 2024 to consumer products offered in a commercial activity, unless sector-specific rules govern the relevant risk. Handmade products and low turnover do not create an automatic exemption.

Product Category Gates

GPSR does not replace specific regulations. A general marketplace cannot open a category just because a product card has a "manufacturer" field. For each category, the operator approves a list of required information and evidence, and then checks it before publication.

BDO, packaging, and EPR: who is actually responsible

BDO does not automatically apply to everyone who sells. It applies to specific roles and product groups. In a marketplace, the most common obligation arises when an entity packages a product and is the first to introduce it in that packaging in Poland, imports/acquires

Consumer Law: Sale, Withdrawal, and Complaint

The buyer should receive clearly and without having to search through multiple documents:

Prices, Promotions, Ranking, Advertising, and Reviews

When a seller communicates a price reduction - a crossed-out price, a percentage, the phrase "promotion," "cheaper," or an equivalent message - the lowest price applied in the 30 days prior to the reduction is displayed next to the current price. If the product has been offered for less than 30 days,

Payments, Payouts, VAT, and Sales Documents

A small and medium marketplace should use a licensed payment provider offering a marketplace product: seller onboarding, accounts/sub-accounts, payment splitting, payout schedules, refunds, chargebacks, holds, and reconciliation reports.

GDPR without myths: what to record, where, and on what basis

Acceptance of the terms and conditions is not GDPR consent for order fulfillment. Data necessary for the account, order, payment, security, and legal obligations are processed on the appropriate basis, e.g., contract performance, legal obligation, or legiti

DSA: reporting, moderation, and seller traceability

The DSA applies to intermediary services in the EU. A marketplace is typically a hosting service and an online platform; some specific obligations depend on its size. However, an exemption does not mean that a micro-platform has no DSA obligations.

P2B: fair rules for business users

The P2B Regulation governs providers of online intermediation services and business users offering goods or services to consumers in the EU. It protects business users in their dealings with platform operators and remains in force.

DAC7: seller data and annual reporting

DAC7 is not a tax imposed by the platform. It is an obligation of due diligence, collection, verification, and reporting by the platform operator, if the software enables sellers to perform the reported activities and the operator knows or can reasonably determine the transaction value.

E-commerce accessibility from June 28, 2025

The Polish Accessibility Act covers e-commerce services. A micro-entrepreneur providing the service is exempt, but a small or medium operator is not. Micro means fewer than 10 people and an annual turnover or balance sheet total not exceeding 2

Cybersecurity and KSC/NIS2

Security is not an add-on to GDPR. The marketplace stores seller identification data, customer addresses, purchase history, and compliance documents. Full payout statements may remain with Stripe/PSP, but account takeover in the marketplace

Retention: How long to store data and evidence

There is no single term 'GDPR = 5 years'. Each data group has its own purpose and basis. The platform implements a retention engine or a regular process that selects the longest applicable term for a specific record, blocks deletion during disputes/incidents, and deletes or anonymizes after the term expires. In MVP, this can be an approved table of terms, periodic export/list of records for deletion, and execution control; an automatic engine is not required.

Post-launch operations: calendar and owners

Four business models - specific decisions

Recommended start: only entrepreneurs from Poland/EU, no shipping from outside the EU, no operator fulfillment, no high-risk categories. The seller is the party to the sale, PSP handles payment separation.

Document and Procedure Package to Prepare

GO / NO-GO Checklist Before Launch

A 'no' answer to a point marked as blocking will halt public sales.

Most Common Misconceptions

Sources and Update Principle

Priority was given to applicable legal acts and materials from relevant authorities, not law firm blogs. Links accompanying chapters lead to the sources used for operational rules. At least once per quarter, the compliance owner checks for changes

Important Disclaimer Regarding the Nature of the Material

This material is for informational and educational purposes only. It contains an author's interpretation of general provisions, official materials, and practical ways to organize a marketplace based on the state of sources as of the indicated date. It does not constitute